老年人心臟性猝死是指急性癥狀發作后1小時內發生的以意識突然喪失為特征的由心臟原(yuan)因(yin)引起的(de)自(zi)(zi)然(ran)死亡(wang)。1979年(nian)(nian)國際心臟病學(xue)會(hui)、美國心臟學(xue)會(hui)以及1970年(nian)(nian)世界衛生(sheng)(sheng)組織定(ding)(ding)義的(de)猝死為:急性癥狀發(fa)生(sheng)(sheng)后(hou)即(ji)刻或(huo)者(zhe)情況24小時內發(fa)生(sheng)(sheng)的(de)意外死亡(wang)。目(mu)前大(da)多數學(xue)者(zhe)傾向于(yu)將(jiang)猝死的(de)時間限定(ding)(ding)在發(fa)病1小時內。其(qi)特點有(you)三,①死亡(wang)急驟,②死亡(wang)出人(ren)意料,③自(zi)(zi)然(ran)死亡(wang)或(huo)非暴(bao)力(li)死亡(wang)。
(1)冠心病
冠心病(bing)(bing)(急性(xing)(xing)缺(que)血事(shi)件,慢(man)性(xing)(xing)缺(que)血性(xing)(xing)心臟病(bing)(bing))是(shi)心臟性(xing)(xing)猝(cu)死(si)的(de)(de)(de)(de)最常見的(de)(de)(de)(de)原因。對心臟性(xing)(xing)猝(cu)死(si)的(de)(de)(de)(de)尸檢發現(xian),大約80%的(de)(de)(de)(de)患者(zhe)具有(you)不同程度的(de)(de)(de)(de)冠狀動脈病(bing)(bing)變,大約2/3以上的(de)(de)(de)(de)患者(zhe)為(wei)2支或(huo)3支以上的(de)(de)(de)(de)病(bing)(bing)變。心肌梗(geng)死(si)后(hou)伴有(you)左心功能下(xia)降(jiang)或(huo)嚴重室性(xing)(xing)心律失常的(de)(de)(de)(de)患者(zhe),心臟性(xing)(xing)猝(cu)死(si)的(de)(de)(de)(de)發生率顯著增加。
(2)心肌病
擴張型(xing)心(xin)(xin)(xin)(xin)肌(ji)(ji)病(bing)(bing)的(de)(de)心(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性猝(cu)死(si)(si)(si)率為(wei)2%,在(zai)(zai)伴(ban)有(you)室性心(xin)(xin)(xin)(xin)律(lv)失(shi)常(chang)時心(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性猝(cu)死(si)(si)(si)率可(ke)明顯增加。而肥厚性心(xin)(xin)(xin)(xin)肌(ji)(ji)病(bing)(bing)患者(zhe)中(zhong)心(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性猝(cu)死(si)(si)(si)更(geng)常(chang)見。大多(duo)數(shu)學者(zhe)報道,肥厚性心(xin)(xin)(xin)(xin)肌(ji)(ji)病(bing)(bing)的(de)(de)年病(bing)(bing)死(si)(si)(si)率為(wei)3%~4%,其中(zhong)大多(duo)數(shu)為(wei)心(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性猝(cu)死(si)(si)(si)。在(zai)(zai)肥厚性心(xin)(xin)(xin)(xin)肌(ji)(ji)病(bing)(bing)患者(zhe),下列(lie)情形為(wei)發生心(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性猝(cu)死(si)(si)(si)的(de)(de)高危因(yin)素:①年齡較輕,在(zai)(zai)30歲(sui)以下。②曾(ceng)有(you)暈厥病(bing)(bing)史(shi)。③既往(wang)有(you)心(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性猝(cu)死(si)(si)(si)的(de)(de)家族史(shi)。此(ci)外,各(ge)種原因(yin)產生的(de)(de)心(xin)(xin)(xin)(xin)肌(ji)(ji)病(bing)(bing)和致(zhi)心(xin)(xin)(xin)(xin)律(lv)失(shi)常(chang)性心(xin)(xin)(xin)(xin)肌(ji)(ji)病(bing)(bing)也(ye)容易發生心(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性猝(cu)死(si)(si)(si)。
(3)心臟瓣膜炎癥浸潤
現(xian)已公(gong)認,二尖瓣(ban)脫垂綜合(he)征可發(fa)(fa)生心臟性(xing)(xing)(xing)猝死,但發(fa)(fa)生率(lv)不高。據Jersaty報道,二尖瓣(ban)脫垂患(huan)(huan)者(zhe)(zhe)伴有(you)下(xia)列情形者(zhe)(zhe)易發(fa)(fa)生心臟性(xing)(xing)(xing)猝死:①40歲左右的女(nv)性(xing)(xing)(xing)患(huan)(huan)者(zhe)(zhe)。②有(you)暈厥病(bing)史。③心電圖上有(you)ST段改變或(huo)有(you)頻發(fa)(fa)室性(xing)(xing)(xing)期前收縮(suo)等(deng)室性(xing)(xing)(xing)心律失常。④有(you)“喀(ka)啦(la)”音和收縮(suo)晚期或(huo)全(quan)收縮(suo)期雜音。
(4)心律失常
一般不易發生心臟性猝死,但在(zai)老年(nian)患者(zhe),常可并發嚴重的冠狀動脈狹窄或高血壓(ya)致嚴重左心室(shi)肥厚型(xing)心肌病的左心室(shi)流出道梗阻時,快(kuai)速性室(shi)上性心律失常發作(zuo)時也易發生心臟性猝死。
多(duo)(duo)數學者(zhe)(zhe)認為,嚴(yan)重的(de)(de)(de)(de)(de)(de)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)失常(chang)(chang)可(ke)發(fa)(fa)(fa)生心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si),尤(you)其(qi)在(zai)患有(you)(you)(you)嚴(yan)重器質性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟病的(de)(de)(de)(de)(de)(de)老年患者(zhe)(zhe)。目前(qian),室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)收(shou)縮(suo)在(zai)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)中的(de)(de)(de)(de)(de)(de)意(yi)義尚(shang)存爭議。有(you)(you)(you)些(xie)學者(zhe)(zhe)發(fa)(fa)(fa)現,室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)收(shou)縮(suo)并(bing)不(bu)能(neng)(neng)(neng)增(zeng)加(jia)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)的(de)(de)(de)(de)(de)(de)發(fa)(fa)(fa)生率,尤(you)其(qi)是(shi)(shi)(shi)無(wu)(wu)明顯器質性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟病基礎的(de)(de)(de)(de)(de)(de)單(dan)純性(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)收(shou)縮(suo)。但也有(you)(you)(you)一些(xie)研究提示,室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)收(shou)縮(suo)本(ben)身即是(shi)(shi)(shi)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)的(de)(de)(de)(de)(de)(de)危(wei)(wei)險(xian)(xian)因素,特(te)別(bie)是(shi)(shi)(shi)嚴(yan)重的(de)(de)(de)(de)(de)(de)冠狀(zhuang)動(dong)脈病變(bian)或(huo)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌梗死(si)后的(de)(de)(de)(de)(de)(de)患者(zhe)(zhe),頻(pin)發(fa)(fa)(fa)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)收(shou)縮(suo)對(dui)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)的(de)(de)(de)(de)(de)(de)發(fa)(fa)(fa)生具有(you)(you)(you)一定的(de)(de)(de)(de)(de)(de)意(yi)義,特(te)別(bie)是(shi)(shi)(shi)合(he)并(bing)有(you)(you)(you)左(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)(shi)肥厚、室(shi)(shi)(shi)(shi)內(nei)傳導阻滯和(he)ST-T改變(bian)者(zhe)(zhe)。而(er)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)過速在(zai)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)中的(de)(de)(de)(de)(de)(de)意(yi)義比室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)收(shou)縮(suo)為大(da)。在(zai)臨床中,我們(men)常(chang)(chang)把室(shi)(shi)(shi)(shi)速或(huo)成對(dui)、多(duo)(duo)源(yuan)及頻(pin)發(fa)(fa)(fa)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)收(shou)縮(suo)稱為復(fu)(fu)雜性(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)失常(chang)(chang)。Morganroth根據復(fu)(fu)雜性(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)失常(chang)(chang)引起心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)的(de)(de)(de)(de)(de)(de)危(wei)(wei)險(xian)(xian)程度,將復(fu)(fu)雜性(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)失常(chang)(chang)分為良性(xing)(xing)(xing)(xing)(xing)占30%,其(qi)左(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)功(gong)(gong)能(neng)(neng)(neng)和(he)血流動(dong)力(li)(li)學均正常(chang)(chang),發(fa)(fa)(fa)生心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)的(de)(de)(de)(de)(de)(de)危(wei)(wei)險(xian)(xian)性(xing)(xing)(xing)(xing)(xing)極小(xiao);潛在(zai)惡性(xing)(xing)(xing)(xing)(xing)占65%,心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟結構輕(qing)度異常(chang)(chang),有(you)(you)(you)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)功(gong)(gong)能(neng)(neng)(neng)不(bu)全(quan)和(he)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)異位激動(dong),如(ru)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)收(shou)縮(suo)和(he)(或(huo))非(fei)持續性(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)速,無(wu)(wu)血流動(dong)力(li)(li)學障礙(ai),但心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)的(de)(de)(de)(de)(de)(de)危(wei)(wei)險(xian)(xian)性(xing)(xing)(xing)(xing)(xing)增(zeng)加(jia);惡性(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)失常(chang)(chang)占5%,幾乎都有(you)(you)(you)血流動(dong)力(li)(li)學表現和(he)體(ti)征(zheng)(暈(yun)(yun)厥,心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)功(gong)(gong)能(neng)(neng)(neng)不(bu)全(quan),心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌缺血或(huo)低(di)血壓(ya))其(qi)發(fa)(fa)(fa)生心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)的(de)(de)(de)(de)(de)(de)危(wei)(wei)險(xian)(xian)性(xing)(xing)(xing)(xing)(xing)最大(da)。臨床上(shang)常(chang)(chang)見5種(zhong)類型(xing):①心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)(shi)率≥230bpm的(de)(de)(de)(de)(de)(de)持續性(xing)(xing)(xing)(xing)(xing)單(dan)形性(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)速。②心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)(shi)率逐(zhu)漸(jian)加(jia)速的(de)(de)(de)(de)(de)(de)室(shi)(shi)(shi)(shi)速或(huo)可(ke)蛻(tui)變(bian)為室(shi)(shi)(shi)(shi)撲和(he)(或(huo))室(shi)(shi)(shi)(shi)顫(zhan)(zhan)趨勢者(zhe)(zhe)。③室(shi)(shi)(shi)(shi)速伴嚴(yan)重血流動(dong)力(li)(li)學障礙(ai)如(ru)暈(yun)(yun)厥,左(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)功(gong)(gong)能(neng)(neng)(neng)不(bu)全(quan)和(he)低(di)血壓(ya)。④多(duo)(duo)形性(xing)(xing)(xing)(xing)(xing)(包括(kuo)長Q-T綜合(he)征(zheng)合(he)并(bing)的(de)(de)(de)(de)(de)(de)尖端扭轉(zhuan)型(xing))室(shi)(shi)(shi)(shi)速。⑤室(shi)(shi)(shi)(shi)撲和(he)(或(huo))室(shi)(shi)(shi)(shi)顫(zhan)(zhan)起始心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)失常(chang)(chang)即為室(shi)(shi)(shi)(shi)撲和(he)(或(huo))室(shi)(shi)(shi)(shi)顫(zhan)(zhan)(如(ru)特(te)發(fa)(fa)(fa)性(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)顫(zhan)(zhan),Brugada綜合(he)征(zheng))。臨床表現為阿(a)-斯綜合(he)征(zheng)發(fa)(fa)(fa)作。而(er)由心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)電圖證(zheng)實的(de)(de)(de)(de)(de)(de)大(da)多(duo)(duo)數心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)發(fa)(fa)(fa)作(65%~85%)是(shi)(shi)(shi)由心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)(shi)顫(zhan)(zhan)動(dong)之類的(de)(de)(de)(de)(de)(de)惡性(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)失常(chang)(chang)所(suo)致。但緩慢性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)失常(chang)(chang)也可(ke)能(neng)(neng)(neng)是(shi)(shi)(shi)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)的(de)(de)(de)(de)(de)(de)潛在(zai)原因,并(bing)可(ke)能(neng)(neng)(neng)在(zai)記錄到緩慢性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)失常(chang)(chang)之前(qian)就(jiu)已轉(zhuan)變(bian)為心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)(shi)顫(zhan)(zhan)動(dong)。
預激(ji)綜合征患者并發房(fang)室折返性(xing)心動(dong)過速、心房(fang)顫動(dong)等(deng)快速性(xing)心律(lv)失常(chang)者占40%~80%。但發生心臟性(xing)猝(cu)死(si)的危險性(xing)較(jiao)低,有調查在(zai)4%以(yi)下(xia),老年患者也(ye)未(wei)見心臟性(xing)猝(cu)死(si)增加的報(bao)道。
(5)其他
糖尿病(bing)除了增加(jia)(jia)冠(guan)心(xin)病(bing)的(de)發生(sheng)率外,本身也可損傷(shang)心(xin)肌而增加(jia)(jia)心(xin)臟(zang)性猝(cu)死(si)的(de)發生(sheng)率。尤其女性患(huan)(huan)者的(de)心(xin)臟(zang)性猝(cu)死(si)發生(sheng)率增加(jia)(jia)更(geng)明顯,較同年(nian)齡組(zu)而無糖尿病(bing)的(de)患(huan)(huan)者增加(jia)(jia)3倍。
目(mu)前已知(zhi),發生心臟性猝死的(de)機制(zhi)主要為(wei)嚴(yan)(yan)重(zhong)的(de)室(shi)性心律失常,包(bao)括室(shi)性心動過速,心室(shi)顫動等(deng)。也(ye)有一部分人為(wei)突然發生的(de)嚴(yan)(yan)重(zhong)血流動力學障礙,心臟破(po)裂(lie)等(deng)。
一般認為,心室顫動是(shi)多發(fa)的(de)折返小波引起的(de)持續性快而不規則的(de)心室激動。心室顫動的(de)發(fa)生必需包括以下幾個基本條件(jian),即(ji)異步和(he)分離的(de)局部波前興奮,傳(chuan)導延緩和(he)心室不應期縮(suo)短。這(zhe)些變化,在缺血的(de)心肌中均可出現。
(1)缺(que)血(xue)性(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)律失常(chang)(chang)(chang):包(bao)括急性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)缺(que)血(xue)所致的室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)律失常(chang)(chang)(chang)和心(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)梗死后(hou)陳(chen)舊性(xing)(xing)(xing)(xing)(xing)病變并(bing)發的室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)律失常(chang)(chang)(chang)。如果急性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)缺(que)血(xue)發生在心(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)梗死后(hou)瘢痕愈合的邊緣(yuan)心(xin)(xin)(xin)(xin)(xin)肌(ji)(ji),則(ze)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)律失常(chang)(chang)(chang)的發生率更高。在急性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)缺(que)血(xue)時(shi),局(ju)部心(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)組織灌注(zhu)不足,導致缺(que)血(xue)部位(wei)(wei)的心(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)能量代謝(xie)較正(zheng)常(chang)(chang)(chang)心(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)組織明顯(xian)降(jiang)低,大(da)量游離(li)脂肪酸(FFA)堆積,細(xi)胞(bao)內乳酸含量增(zeng)加,細(xi)胞(bao)內鉀、鎂離(li)子外流(liu),則(ze)靜息電位(wei)(wei)的負(fu)值進(jin)一步增(zeng)加,形(xing)成舒張期電位(wei)(wei)。同時(shi),動作電位(wei)(wei)的振幅下降(jiang),去極化的速(su)(su)度減慢,興奮傳導速(su)(su)度減慢,則(ze)心(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)自律性(xing)(xing)(xing)(xing)(xing)增(zeng)強(qiang),并(bing)易(yi)于(yu)(yu)形(xing)成折(zhe)返的條件而(er)發生室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)折(zhe)返性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)律失常(chang)(chang)(chang)及心(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)顫(zhan)動。而(er)同時(shi)存在左心(xin)(xin)(xin)(xin)(xin)功能不全的患者,心(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝死的發生率則(ze)更高,尤其左室(shi)(shi)(shi)射血(xue)分(fen)數(shu)低于(yu)(yu)30%是心(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝死的最強(qiang)的預測因素。
現(xian)已知(zhi)再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)是(shi)發(fa)(fa)生(sheng)(sheng)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)(xing)(xing)(xing)(xing)(xing)猝死的(de)(de)(de)(de)重(zhong)要(yao)機制(zhi)(zhi)。再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)可(ke)見(jian)于冠(guan)狀(zhuang)動(dong)(dong)脈痙攣(luan)緩解以后(hou),也(ye)可(ke)見(jian)于急性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)梗死溶栓治療(liao)或(huo)機械性(xing)(xing)(xing)(xing)(xing)(xing)粉碎斑(ban)塊后(hou)使完全閉塞的(de)(de)(de)(de)血管再(zai)(zai)(zai)通(tong)(tong)等情況。常(chang)(chang)(chang)在冠(guan)狀(zhuang)動(dong)(dong)脈再(zai)(zai)(zai)通(tong)(tong)后(hou)幾(ji)秒(miao)鐘而出現(xian)再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)。許(xu)多研究表(biao)明,冠(guan)狀(zhuang)動(dong)(dong)脈再(zai)(zai)(zai)通(tong)(tong)時(shi),再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)的(de)(de)(de)(de)發(fa)(fa)生(sheng)(sheng)率高達(da)82%。在再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)的(de)(de)(de)(de)不(bu)同類型中(zhong)60%~80%為(wei)加(jia)速(su)(su)性(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)自(zi)主心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)和(he)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)期前收縮,可(ke)引起(qi)(qi)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)(xing)(xing)(xing)(xing)(xing)猝死的(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)為(wei)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)(dong)過(guo)速(su)(su)和(he)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)顫(zhan)動(dong)(dong),嚴重(zhong)的(de)(de)(de)(de)緩慢性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)也(ye)可(ke)引起(qi)(qi)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)(xing)(xing)(xing)(xing)(xing)猝死。而再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)的(de)(de)(de)(de)類型和(he)冠(guan)狀(zhuang)動(dong)(dong)脈的(de)(de)(de)(de)再(zai)(zai)(zai)通(tong)(tong)部位(wei)(wei)(wei)有(you)一定(ding)的(de)(de)(de)(de)關(guan)系。左(zuo)前降(jiang)支(zhi)和(he)左(zuo)旋支(zhi)再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)時(shi)易發(fa)(fa)生(sheng)(sheng)加(jia)速(su)(su)性(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)自(zi)主心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv),室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)(dong)過(guo)速(su)(su)和(he)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)顫(zhan)動(dong)(dong)。右(you)冠(guan)狀(zhuang)動(dong)(dong)脈阻(zu)塞再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)時(shi)易發(fa)(fa)生(sheng)(sheng)竇(dou)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)(dong)過(guo)緩,房室(shi)(shi)傳導阻(zu)滯。實驗研究提示,再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)的(de)(de)(de)(de)發(fa)(fa)生(sheng)(sheng)機制(zhi)(zhi)包括觸(chu)(chu)發(fa)(fa)激(ji)(ji)(ji)動(dong)(dong)、折(zhe)(zhe)返激(ji)(ji)(ji)動(dong)(dong)和(he)異(yi)位(wei)(wei)(wei)自(zi)律(lv)(lv)(lv)(lv)性(xing)(xing)(xing)(xing)(xing)(xing)增高。目前多數學者認(ren)為(wei),觸(chu)(chu)發(fa)(fa)激(ji)(ji)(ji)動(dong)(dong)在再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)的(de)(de)(de)(de)發(fa)(fa)生(sheng)(sheng)中(zhong)占(zhan)據(ju)重(zhong)要(yao)位(wei)(wei)(wei)置。而折(zhe)(zhe)返機制(zhi)(zhi)的(de)(de)(de)(de)產生(sheng)(sheng)可(ke)能與再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)后(hou)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)細(xi)(xi)胞(bao)電(dian)(dian)生(sheng)(sheng)理恢(hui)復不(bu)均勻有(you)關(guan)。心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)缺(que)血性(xing)(xing)(xing)(xing)(xing)(xing)損傷使心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)細(xi)(xi)胞(bao)的(de)(de)(de)(de)電(dian)(dian)生(sheng)(sheng)理改變不(bu)均勻,血管再(zai)(zai)(zai)通(tong)(tong)后(hou)的(de)(de)(de)(de)再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)使血流恢(hui)復,但恢(hui)復血流后(hou)的(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)細(xi)(xi)胞(bao)血液供(gong)應和(he)代謝(xie)恢(hui)復也(ye)不(bu)均勻,結果(guo)導致(zhi)缺(que)血區內心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)應激(ji)(ji)(ji)性(xing)(xing)(xing)(xing)(xing)(xing)的(de)(de)(de)(de)恢(hui)復程(cheng)度不(bu)一致(zhi),則易于形成折(zhe)(zhe)返而引起(qi)(qi)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)(dong)過(guo)速(su)(su)和(he)(或(huo))心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)顫(zhan)動(dong)(dong)。此外,心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)缺(que)血-再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)損傷也(ye)可(ke)引起(qi)(qi)異(yi)位(wei)(wei)(wei)興(xing)奮灶的(de)(de)(de)(de)自(zi)律(lv)(lv)(lv)(lv)性(xing)(xing)(xing)(xing)(xing)(xing)增加(jia),引起(qi)(qi)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)。Pogwizd等用心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)三維標測技術研究表(biao)明,75%的(de)(de)(de)(de)再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)是(shi)由觸(chu)(chu)發(fa)(fa)激(ji)(ji)(ji)動(dong)(dong)引起(qi)(qi)的(de)(de)(de)(de),25%的(de)(de)(de)(de)再(zai)(zai)(zai)灌(guan)(guan)注(zhu)(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)是(shi)由折(zhe)(zhe)返機制(zhi)(zhi)引起(qi)(qi)。
病(bing)因不明,無明顯冠狀動脈或心(xin)肌本身的(de)病(bing)變(bian),常常突然或在某(mou)些誘(you)因的(de)作用下發生(sheng)嚴重的(de)室(shi)(shi)性(xing)心(xin)律失(shi)常和(或)心(xin)室(shi)(shi)顫動,而發生(sheng)心(xin)臟性(xing)猝死。研究表明,原發性(xing)室(shi)(shi)性(xing)心(xin)律失(shi)常的(de)發生(sheng)機制(zhi)多為觸(chu)發激動,也有的(de)為折返(fan)機制(zhi)。
Raizes等(deng)研究表明,非心(xin)(xin)(xin)(xin)(xin)(xin)律失常(chang)引(yin)起的(de)(de)(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)猝死只占0.56%,包括心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)(zang)或主動(dong)脈破裂,心(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)梗死擴(kuo)展,交感神經反射性(xing)(xing)(xing)(xing)抑制,以及各(ge)種原因引(yin)起的(de)(de)(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)(zang)嚴重(zhong)的(de)(de)(de)(de)(de)(de)機械性(xing)(xing)(xing)(xing)梗阻等(deng)。尤其伴(ban)(ban)有(you)左(zuo)(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)功(gong)能不全的(de)(de)(de)(de)(de)(de)患(huan)者心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)猝死的(de)(de)(de)(de)(de)(de)發生率最高。左(zuo)(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)功(gong)能不全又常(chang)有(you)冠(guan)狀動(dong)脈病變(bian)(bian)和彌漫的(de)(de)(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)病變(bian)(bian),因而(er)(er)可(ke)伴(ban)(ban)有(you)急性(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)缺血或心(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)瘢痕組織(zhi)所(suo)誘發的(de)(de)(de)(de)(de)(de)惡(e)性(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)律失常(chang),從而(er)(er)導致心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)猝死。在冠(guan)心(xin)(xin)(xin)(xin)(xin)(xin)病合并左(zuo)(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)室(shi)功(gong)能不全致心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)猝死事(shi)件(jian)中,36%表現為(wei)(wei)嚴重(zhong)心(xin)(xin)(xin)(xin)(xin)(xin)動(dong)過緩或電(dian)(dian)-機械分(fen)離。心(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)(zang)驟停前(qian)并未伴(ban)(ban)心(xin)(xin)(xin)(xin)(xin)(xin)力衰竭癥狀的(de)(de)(de)(de)(de)(de)惡(e)化。緩慢性(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)律失常(chang)或電(dian)(dian)-機械分(fen)離可(ke)能因左(zuo)(zuo)室(shi)收(shou)縮(suo)功(gong)能衰竭終末(mo)期(qi)心(xin)(xin)(xin)(xin)(xin)(xin)室(shi)壁應(ying)激(ji)時使心(xin)(xin)(xin)(xin)(xin)(xin)室(shi)內壓力和容(rong)量突然增加,而(er)(er)周(zhou)圍血管(guan)收(shou)縮(suo)同時出現障(zhang)礙,不能維持體循環血壓,以至(zhi)虛脫和暈厥。猝死則為(wei)(wei)血流(liu)動(dong)力學障(zhang)礙所(suo)致,并非心(xin)(xin)(xin)(xin)(xin)(xin)電(dian)(dian)不穩定事(shi)件(jian)。另(ling)一(yi)部(bu)分(fen)左(zuo)(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)功(gong)能不全的(de)(de)(de)(de)(de)(de)患(huan)者伴(ban)(ban)有(you)室(shi)性(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)動(dong)過速,則可(ke)能為(wei)(wei)心(xin)(xin)(xin)(xin)(xin)(xin)律失常(chang)所(suo)致。
(2)心(xin)臟(zang)性(xing)猝死后(hou)的病生理變(bian)化
原發(fa)(fa)(fa)性(xing)改變(bian):心(xin)(xin)(xin)(xin)(xin)臟性(xing)猝(cu)(cu)死(si)(si)的(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)臟病(bing)(bing)理改變(bian)資料(liao)(liao)主要來(lai)自(zi)尸體(ti)解剖。但不同學者(zhe)所報道(dao)的(de)(de)(de)(de)尸體(ti)解剖病(bing)(bing)理結(jie)果有很(hen)大的(de)(de)(de)(de)不一致,且多數(shu)學者(zhe)研究為(wei)冠(guan)(guan)心(xin)(xin)(xin)(xin)(xin)病(bing)(bing)猝(cu)(cu)死(si)(si)。從冠(guan)(guan)心(xin)(xin)(xin)(xin)(xin)病(bing)(bing)猝(cu)(cu)死(si)(si)的(de)(de)(de)(de)病(bing)(bing)理資料(liao)(liao)來(lai)看,主要病(bing)(bing)理結(jie)果為(wei)冠(guan)(guan)狀(zhuang)動脈狹窄程度重,冠(guan)(guan)狀(zhuang)動脈內(nei)并發(fa)(fa)(fa)血(xue)(xue)(xue)栓形成,心(xin)(xin)(xin)(xin)(xin)肌出現(xian)(xian)嚴重的(de)(de)(de)(de)缺血(xue)(xue)(xue)或梗(geng)(geng)死(si)(si)。Schwartz等發(fa)(fa)(fa)現(xian)(xian),1/3以上的(de)(de)(de)(de)冠(guan)(guan)心(xin)(xin)(xin)(xin)(xin)病(bing)(bing)猝(cu)(cu)死(si)(si)患(huan)者(zhe)的(de)(de)(de)(de)冠(guan)(guan)狀(zhuang)動脈內(nei)有血(xue)(xue)(xue)栓形成。國內(nei)外的(de)(de)(de)(de)一些資料(liao)(liao)提示:冠(guan)(guan)心(xin)(xin)(xin)(xin)(xin)病(bing)(bing)猝(cu)(cu)死(si)(si)患(huan)者(zhe)中急性(xing)心(xin)(xin)(xin)(xin)(xin)肌梗(geng)(geng)死(si)(si)的(de)(de)(de)(de)發(fa)(fa)(fa)生(sheng)(sheng)(sheng)率約為(wei)40%,并且冠(guan)(guan)心(xin)(xin)(xin)(xin)(xin)病(bing)(bing)猝(cu)(cu)死(si)(si)患(huan)者(zhe)的(de)(de)(de)(de)竇房(fang)結(jie)和(he)傳導(dao)系統(tong)并無(wu)明顯的(de)(de)(de)(de)急性(xing)病(bing)(bing)變(bian),亦證實了冠(guan)(guan)心(xin)(xin)(xin)(xin)(xin)病(bing)(bing)猝(cu)(cu)死(si)(si)的(de)(de)(de)(de)發(fa)(fa)(fa)生(sheng)(sheng)(sheng)機制(zhi)為(wei)心(xin)(xin)(xin)(xin)(xin)電不穩定所致。心(xin)(xin)(xin)(xin)(xin)臟性(xing)猝(cu)(cu)死(si)(si)很(hen)少發(fa)(fa)(fa)生(sheng)(sheng)(sheng)在沒有器質性(xing)心(xin)(xin)(xin)(xin)(xin)臟病(bing)(bing)的(de)(de)(de)(de)患(huan)者(zhe)。有些患(huan)者(zhe)發(fa)(fa)(fa)生(sheng)(sheng)(sheng)心(xin)(xin)(xin)(xin)(xin)臟性(xing)猝(cu)(cu)死(si)(si)后,即使心(xin)(xin)(xin)(xin)(xin)臟的(de)(de)(de)(de)大體(ti)檢查(cha)無(wu)明顯肉(rou)眼(yan)病(bing)(bing)變(bian),但可能(neng)其心(xin)(xin)(xin)(xin)(xin)臟的(de)(de)(de)(de)分子(zi)結(jie)構(gou)和(he)功能(neng)也存在著明顯的(de)(de)(de)(de)異(yi)常。如離子(zi)通道(dao)、蛋白質結(jie)構(gou)異(yi)常等。
繼發性改(gai)變:正常心(xin)(xin)(xin)(xin)(xin)臟做(zuo)功所(suo)需能(neng)量首先來(lai)自脂肪,約占心(xin)(xin)(xin)(xin)(xin)肌(ji)總(zong)耗(hao)氧量的(de)(de)67%,其次(ci)來(lai)自葡(pu)萄(tao)糖和(he)乳酸(suan),分別(bie)占17.9%和(he)16.46%,極少數來(lai)自醋酸(suan)、氨基酸(suan)、丙(bing)酮(tong)酸(suan)等。同(tong)時心(xin)(xin)(xin)(xin)(xin)臟必須依賴ATP來(lai)維(wei)持其心(xin)(xin)(xin)(xin)(xin)室(shi)壁的(de)(de)張(zhang)(zhang)力和(he)收縮狀態。研究(jiu)表(biao)明,心(xin)(xin)(xin)(xin)(xin)肌(ji)缺(que)血(xue)缺(que)氧10s即可(ke)(ke)代謝底物耗(hao)竭,心(xin)(xin)(xin)(xin)(xin)臟即完全失去收縮功能(neng)。在常溫(wen)下,如(ru)果(guo)心(xin)(xin)(xin)(xin)(xin)肌(ji)缺(que)血(xue)3~4min,心(xin)(xin)(xin)(xin)(xin)肌(ji)內磷酸(suan)肌(ji)酸(suan)含(han)量減(jian)少70%~75%,ATP減(jian)少15%。如(ru)在此(ci)(ci)期內進(jin)行(xing)有效(xiao)的(de)(de)心(xin)(xin)(xin)(xin)(xin)肺(fei)復(fu)蘇,心(xin)(xin)(xin)(xin)(xin)肌(ji)供血(xue)改(gai)善(shan),則心(xin)(xin)(xin)(xin)(xin)肌(ji)張(zhang)(zhang)力可(ke)(ke)完全恢復(fu);缺(que)血(xue)8~10min,心(xin)(xin)(xin)(xin)(xin)肌(ji)內磷酸(suan)肌(ji)酸(suan)和(he)ATP將全部耗(hao)盡(jin),如(ru)在此(ci)(ci)期內進(jin)行(xing)有效(xiao)的(de)(de)心(xin)(xin)(xin)(xin)(xin)肺(fei)復(fu)蘇,心(xin)(xin)(xin)(xin)(xin)臟的(de)(de)收縮和(he)舒張(zhang)(zhang)功能(neng)仍可(ke)(ke)恢復(fu),10min后才進(jin)行(xing)有效(xiao)的(de)(de)心(xin)(xin)(xin)(xin)(xin)肺(fei)復(fu)蘇者,復(fu)蘇的(de)(de)成功機會顯著(zhu)減(jian)少。
腦(nao)(nao)(nao)(nao):腦(nao)(nao)(nao)(nao)的(de)(de)(de)能(neng)(neng)量代(dai)(dai)謝主要來(lai)(lai)自葡萄糖,但腦(nao)(nao)(nao)(nao)組(zu)織本身對葡萄糖的(de)(de)(de)儲備很少,必須(xu)依賴于循環血(xue)液來(lai)(lai)供(gong)(gong)應(ying)。并且腦(nao)(nao)(nao)(nao)組(zu)織的(de)(de)(de)代(dai)(dai)謝85%~90%為有氧(yang)代(dai)(dai)謝,而無氧(yang)酵解(jie)只占(zhan)腦(nao)(nao)(nao)(nao)組(zu)織代(dai)(dai)謝的(de)(de)(de)5%~15%,所(suo)以,腦(nao)(nao)(nao)(nao)組(zu)織的(de)(de)(de)代(dai)(dai)謝和(he)(he)生(sheng)(sheng)理功能(neng)(neng)的(de)(de)(de)維持則完(wan)全依賴于有效的(de)(de)(de)血(xue)液供(gong)(gong)應(ying)。血(xue)液供(gong)(gong)應(ying)障礙引起腦(nao)(nao)(nao)(nao)細(xi)胞(bao)(bao)功能(neng)(neng)的(de)(de)(de)改(gai)變(bian)(bian)的(de)(de)(de)基礎(chu)是缺(que)血(xue)缺(que)氧(yang)引起腦(nao)(nao)(nao)(nao)組(zu)織的(de)(de)(de)原發(fa)(fa)和(he)(he)繼發(fa)(fa)損害。原發(fa)(fa)損害為腦(nao)(nao)(nao)(nao)組(zu)織缺(que)血(xue)缺(que)氧(yang)時,ATP不(bu)(bu)能(neng)(neng)合成,細(xi)胞(bao)(bao)鈉泵(beng)功能(neng)(neng)喪失,細(xi)胞(bao)(bao)內(nei)鈉離子不(bu)(bu)能(neng)(neng)轉(zhuan)運到細(xi)胞(bao)(bao)外,鉀離子不(bu)(bu)能(neng)(neng)從細(xi)胞(bao)(bao)內(nei)逸出,細(xi)胞(bao)(bao)膜電(dian)(dian)位發(fa)(fa)生(sheng)(sheng)改(gai)變(bian)(bian),因此(ci)不(bu)(bu)能(neng)(neng)產生(sheng)(sheng)電(dian)(dian)活(huo)動(dong)(dong),細(xi)胞(bao)(bao)也失去了產生(sheng)(sheng)和(he)(he)傳(chuan)導沖動(dong)(dong)的(de)(de)(de)功能(neng)(neng)。研究表明(ming),在完(wan)全缺(que)氧(yang)情況下,20s后大(da)腦(nao)(nao)(nao)(nao)皮質(zhi)的(de)(de)(de)生(sheng)(sheng)物電(dian)(dian)活(huo)動(dong)(dong)完(wan)全消(xiao)失,30~90s后小腦(nao)(nao)(nao)(nao)和(he)(he)延髓的(de)(de)(de)生(sheng)(sheng)物電(dian)(dian)活(huo)動(dong)(dong)完(wan)全消(xiao)失。而缺(que)血(xue)缺(que)氧(yang)所(suo)致(zhi)的(de)(de)(de)繼發(fa)(fa)損害包括兩個方面:
A.細胞內(nei)電解質紊亂和各種代謝產物的(de)堆積而使(shi)腦組織腫脹和腦水(shui)腫。
B.腦(nao)(nao)組(zu)織(zhi)(zhi)的局部循環功(gong)能(neng)障(zhang)礙進(jin)一步加重(zhong)。已有研究提示,心臟(zang)驟停(ting)引(yin)起的腦(nao)(nao)組(zu)織(zhi)(zhi)缺(que)血(xue)(xue)(xue)缺(que)氧(yang)時,病變主要在大腦(nao)(nao)海馬回先出現,如缺(que)血(xue)(xue)(xue)進(jin)一步加重(zhong),則迅速波(bo)及(ji)全腦(nao)(nao),包(bao)括腦(nao)(nao)干和延(yan)髓(sui)。而患(huan)者(zhe)(zhe)發生(sheng)心臟(zang)性猝死后,如果能(neng)及(ji)時、有效(xiao)地進(jin)行心肺復蘇,則腦(nao)(nao)組(zu)織(zhi)(zhi)的血(xue)(xue)(xue)流(liu)有可能(neng)恢(hui)復,但腦(nao)(nao)組(zu)織(zhi)(zhi)由于受到完全缺(que)血(xue)(xue)(xue)缺(que)氧(yang)的影響(xiang),腦(nao)(nao)水腫和微循環障(zhang)礙將繼續發展。腦(nao)(nao)組(zu)織(zhi)(zhi)的缺(que)血(xue)(xue)(xue)缺(que)氧(yang)時間長(chang)短直接(jie)影響(xiang)大腦(nao)(nao)功(gong)能(neng)的恢(hui)復及(ji)患(huan)者(zhe)(zhe)的臨床(chuang)預后。
腎:
心臟驟停時,腎(shen)(shen)臟的血流供應(ying)和濾過(guo)功(gong)能完全停止。首(shou)先受累(lei)的是腎(shen)(shen)小(xiao)管,引起腎(shen)(shen)小(xiao)管細胞壞(huai)死,并逐步(bu)累(lei)及(ji)基底(di)膜及(ji)整個腎(shen)(shen)單位。如(ru)果發(fa)生(sheng)時間短,基底(di)膜可保持(chi)相對完整,腎(shen)(shen)臟功(gong)能可恢(hui)復(fu),但缺血缺氧(yang)的時間過(guo)長,腎(shen)(shen)小(xiao)管及(ji)腎(shen)(shen)小(xiao)球產生(sheng)廣泛的嚴重破壞(huai),則易(yi)發(fa)生(sheng)急(ji)性腎(shen)(shen)功(gong)能衰竭。
肺(fei)(fei):發(fa)生(sheng)(sheng)心(xin)臟(zang)性猝死后,肺(fei)(fei)可(ke)發(fa)生(sheng)(sheng)淤血(xue)、水腫。顯微鏡下(xia)其主要特征是肺(fei)(fei)間質水腫,并可(ke)見微血(xue)栓形成。長(chang)時間的肺(fei)(fei)缺(que)血(xue)缺(que)氧(yang)容易發(fa)生(sheng)(sheng)彌漫性血(xue)管(guan)內凝血(xue),不僅可(ke)通過(guo)機械堵塞使肺(fei)(fei)部缺(que)血(xue)缺(que)氧(yang)進(jin)一(yi)步加重,而(er)且還可(ke)引起血(xue)小板聚集,釋放5-HT等物質產生(sheng)(sheng)終末(mo)氣道痙攣,結(jie)果血(xue)液-氣體(ti)交換障礙(ai)進(jin)一(yi)步惡(e)化。
(3)與心(xin)臟性(xing)猝死發生(sheng)的相(xiang)關因素
自主神(shen)(shen)經(jing)系統在(zai)(zai)心(xin)臟(zang)(zang)性(xing)猝(cu)死(si)的(de)(de)(de)(de)發(fa)(fa)(fa)生(sheng)(sheng)中具有重要作用。臨(lin)床(chuang)觀察發(fa)(fa)(fa)現,冠心(xin)病患者的(de)(de)(de)(de)心(xin)臟(zang)(zang)性(xing)猝(cu)死(si)常發(fa)(fa)(fa)生(sheng)(sheng)在(zai)(zai)凌(ling)晨至(zhi)午間這段時間,與自主神(shen)(shen)經(jing)活(huo)動的(de)(de)(de)(de)晝夜節律性(xing)變化相一致(zhi)(zhi)。此時間段,交感神(shen)(shen)經(jing)活(huo)動較高,血(xue)(xue)(xue)(xue)壓與心(xin)率增(zeng)加,血(xue)(xue)(xue)(xue)小板聚(ju)集性(xing)也增(zeng)加。實驗研究(jiu)表明,刺激(ji)心(xin)臟(zang)(zang)的(de)(de)(de)(de)交感神(shen)(shen)經(jing)可降(jiang)低室(shi)(shi)(shi)顫閾(yu)值,增(zeng)加室(shi)(shi)(shi)顫發(fa)(fa)(fa)生(sheng)(sheng)的(de)(de)(de)(de)危險性(xing);刺激(ji)迷走神(shen)(shen)經(jing),可降(jiang)低室(shi)(shi)(shi)顫發(fa)(fa)(fa)生(sheng)(sheng)的(de)(de)(de)(de)危險性(xing)。所以交感神(shen)(shen)經(jing)的(de)(de)(de)(de)過度興(xing)奮(fen)可促(cu)進惡性(xing)室(shi)(shi)(shi)性(xing)心(xin)律失(shi)常的(de)(de)(de)(de)發(fa)(fa)(fa)生(sheng)(sheng),而興(xing)奮(fen)迷走神(shen)(shen)經(jing)則具有保護心(xin)臟(zang)(zang)及抗室(shi)(shi)(shi)顫的(de)(de)(de)(de)作用。但是(shi),對下后壁(bi)急(ji)性(xing)心(xin)肌缺(que)血(xue)(xue)(xue)(xue)或缺(que)血(xue)(xue)(xue)(xue)性(xing)再灌(guan)注(zhu)的(de)(de)(de)(de)患者,因迷走神(shen)(shen)經(jing)的(de)(de)(de)(de)傳(chuan)入受體多數分布在(zai)(zai)心(xin)室(shi)(shi)(shi)的(de)(de)(de)(de)下后壁(bi),該(gai)部位(wei)發(fa)(fa)(fa)生(sheng)(sheng)心(xin)肌缺(que)血(xue)(xue)(xue)(xue)或缺(que)血(xue)(xue)(xue)(xue)后再灌(guan)注(zhu),可觸發(fa)(fa)(fa)Bezold-Jarish反射(she),導(dao)致(zhi)(zhi)或加重緩慢性(xing)心(xin)律失(shi)常,如嚴重竇性(xing)心(xin)動過緩,高度房室(shi)(shi)(shi)傳(chuan)導(dao)阻滯,周圍(wei)血(xue)(xue)(xue)(xue)管(guan)擴張(zhang)和低血(xue)(xue)(xue)(xue)壓,嚴重者可發(fa)(fa)(fa)生(sheng)(sheng)心(xin)臟(zang)(zang)驟停。
許多心(xin)(xin)臟(zang)(zang)性猝死的患者(zhe)發(fa)生(sheng)在睡(shui)眠中。其機制主要(yao)為睡(shui)眠時迷走神經興(xing)奮,冠(guan)(guan)狀動脈(mo)痙攣,心(xin)(xin)臟(zang)(zang)傳導系統發(fa)生(sheng)缺氧,心(xin)(xin)電不穩定(ding),發(fa)生(sheng)室顫而引起心(xin)(xin)臟(zang)(zang)性猝死。但目(mu)前(qian)尚未能提供冠(guan)(guan)狀動脈(mo)痙攣的形態學(xue)依據。
(1)心臟病發作前(qian),身(shen)體上例如(ru)頸、后背、頭皮、手心或者腳掌都會(hui)大量(liang)出汗,此時應(ying)提(ti)高警惕,當心猝死發生,最好停止(zhi)活動(dong)休息,及(ji)時服用藥(yao)物,必要時應(ying)立即撥打120。
(2)在無(wu)激(ji)烈運動、缺少睡眠或者生病等誘因的(de)情況下,連續幾天、幾周(zhou)甚至(zhi)幾月(yue)出現(xian)極(ji)度疲勞感,伴有焦慮、失眠、無(wu)癥狀驚醒(xing)等癥狀,此(ci)時應考慮心臟出現(xian)問題。
(3)心(xin)(xin)臟病患者經常感到肩膀、頸(jing)部、下巴、手(shou)臂疼痛(tong),這是心(xin)(xin)肌缺血的(de)信號(hao),因為心(xin)(xin)肌缺血疼痛(tong)在(zai)傳遞至大腦中樞神經時,會同時反映(ying)在(zai)水(shui)平(ping)相(xiang)同的(de)脊髓(sui)段區域。
(4)心(xin)(xin)臟病(bing)發(fa)作前的典型癥(zheng)狀是突然(ran)、或者無緣由的心(xin)(xin)跳加劇,一旦發(fa)生心(xin)(xin)室(shi)性心(xin)(xin)搏過(guo)速,則極有可能(neng)在短時間(jian)內突然(ran)死亡。
(5)很多心源性猝死(si)(si)患(huan)者在死(si)(si)亡前(qian)都(dou)反復出(chu)現胃腸道癥(zheng)狀,不少人(ren)生前(qian)并沒有胃病病史(shi),這(zhe)是(shi)(shi)心臟(zang)病發作的信號之一,腸胃不適是(shi)(shi)因為(wei)心血管出(chu)現異常。動脈由(you)于脂肪沉積(ji)物堵塞將會(hui)減(jian)少甚至阻斷血液傳輸給心臟(zang),而這(zhe)會(hui)引(yin)起心絞(jiao)痛(tong)。
心(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)猝死的經過大體(ti)上可(ke)分為4 個時(shi)(shi)期。即前(qian)驅(qu)期,終末(mo)事件開始(shi),心(xin)(xin)(xin)(xin)(xin)臟驟(zou)停(ting)和生(sheng)物學死亡。不(bu)同的患者各(ge)期表(biao)現(xian)(xian)也有(you)(you)(you)明顯(xian)(xian)差異(yi)(yi)。在發生(sheng)心(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)猝死的前(qian)數(shu)天到數(shu)月(yue),有(you)(you)(you)些患者可(ke)出(chu)現(xian)(xian)心(xin)(xin)(xin)(xin)(xin)前(qian)區不(bu)適、心(xin)(xin)(xin)(xin)(xin)悸、氣(qi)短(duan)、乏力等非特異(yi)(yi)性(xing)(xing)表(biao)現(xian)(xian)。但亦可(ke)無前(qian)驅(qu)表(biao)現(xian)(xian),直接(jie)發生(sheng)心(xin)(xin)(xin)(xin)(xin)臟驟(zou)停(ting)。而有(you)(you)(you)些報道佩帶動(dong)(dong)態心(xin)(xin)(xin)(xin)(xin)電(dian)圖的猝死患者,當時(shi)(shi)心(xin)(xin)(xin)(xin)(xin)電(dian)記錄(lu)多(duo)為心(xin)(xin)(xin)(xin)(xin)室顫(zhan)動(dong)(dong),說明心(xin)(xin)(xin)(xin)(xin)臟驟(zou)停(ting)時(shi)(shi)多(duo)為心(xin)(xin)(xin)(xin)(xin)室顫(zhan)動(dong)(dong)。部分患者先(xian)有(you)(you)(you)心(xin)(xin)(xin)(xin)(xin)臟缺(que)(que)血或(huo)左室功能不(bu)全癥狀(zhuang)(zhuang),迅即發生(sheng)心(xin)(xin)(xin)(xin)(xin)臟驟(zou)停(ting)。心(xin)(xin)(xin)(xin)(xin)臟驟(zou)停(ting)前(qian)未訴(su)有(you)(you)(you)不(bu)適感覺(jue)者,是(shi)否有(you)(you)(you)無癥狀(zhuang)(zhuang)心(xin)(xin)(xin)(xin)(xin)肌缺(que)(que)血則不(bu)能確(que)定。心(xin)(xin)(xin)(xin)(xin)臟驟(zou)停(ting)后(hou)腦血流銳減,可(ke)導致意識突然喪失(shi)(shi)。下列體(ti)征有(you)(you)(you)助于判斷是(shi)否發生(sheng)心(xin)(xin)(xin)(xin)(xin)臟驟(zou)停(ting):意識喪失(shi)(shi),頸、股動(dong)(dong)脈(mo)搏動(dong)(dong)消(xiao)失(shi)(shi),呼吸斷續(xu)或(huo)停(ting)止,皮膚蒼白(bai)或(huo)明顯(xian)(xian)發紺。如聽診心(xin)(xin)(xin)(xin)(xin)音消(xiao)失(shi)(shi)更可(ke)確(que)立(li)診斷。經檢(jian)查確(que)立(li)診斷后(hou),應立(li)即進行有(you)(you)(you)效的心(xin)(xin)(xin)(xin)(xin)肺復蘇(su)。
(1)心電圖
目前(qian)已知,心(xin)(xin)肌(ji)肥厚是(shi)心(xin)(xin)臟性(xing)猝死的標志(zhi)性(xing)心(xin)(xin)電圖(tu)。QRS波(bo)群高電壓(ya)和側壁導聯明(ming)顯的間隔部Q波(bo)的出現可(ke)能是(shi)猝死的危險因(yin)素。大(da)面積(ji)前(qian)壁心(xin)(xin)肌(ji)梗(geng)死的患者,心(xin)(xin)電圖(tu)出現右(you)束支阻(zu)滯,6個月的猝死風險約30%。
(2)動態心(xin)電(dian)圖(Holter)
動(dong)態心(xin)電圖可使39%~82%的(de)(de)室(shi)性(xing)(xing)心(xin)律(lv)(lv)(lv)失(shi)常患者得到診斷,并能了解(jie)室(shi)性(xing)(xing)心(xin)律(lv)(lv)(lv)失(shi)常的(de)(de)頻度、復雜程度、晝夜節(jie)律(lv)(lv)(lv)等變(bian)化,尤(you)其是(shi)心(xin)肌梗死(si)和嚴重的(de)(de)冠心(xin)病患者。動(dong)態心(xin)電圖發現的(de)(de)室(shi)性(xing)(xing)心(xin)律(lv)(lv)(lv)失(shi)常對心(xin)臟(zang)性(xing)(xing)猝死(si)的(de)(de)發生有(you)明確的(de)(de)預(yu)測價值。心(xin)臟(zang)性(xing)(xing)猝死(si)的(de)(de)危險性(xing)(xing)隨著(zhu)室(shi)性(xing)(xing)心(xin)律(lv)(lv)(lv)失(shi)常的(de)(de)復雜性(xing)(xing)和頻發性(xing)(xing)而(er)增加(jia)。
(3)運動試驗
有研究表明,運動試(shi)驗對心肌(ji)梗死(si)(si)后的(de)患者發(fa)生心臟性猝死(si)(si)有一定的(de)預測價值。
(4)心室晚(wan)電位
(ventricular late potential,VLP) 心(xin)(xin)(xin)(xin)室(shi)晚(wan)電(dian)(dian)位是體表記錄到(dao)的局部心(xin)(xin)(xin)(xin)室(shi)延(yan)遲(chi)碎裂電(dian)(dian)活動,一(yi)般出現(xian)在(zai)QRS終末(mo)部并可延(yan)伸(shen)到(dao)ST內,呈高頻(20~80Hz)、低幅(25V=碎裂波),持續10s以上。從(cong)目前已有的資料(liao)來看,心(xin)(xin)(xin)(xin)室(shi)晚(wan)電(dian)(dian)位在(zai)預測患者發生致命性(xing)(xing)快速性(xing)(xing)心(xin)(xin)(xin)(xin)律失常方面具有一(yi)定的價值。Brethard等(deng)報道,冠心(xin)(xin)(xin)(xin)病(bing)患者伴有心(xin)(xin)(xin)(xin)室(shi)晚(wan)電(dian)(dian)位陽性(xing)(xing)者,發生心(xin)(xin)(xin)(xin)臟(zang)性(xing)(xing)猝死(si)的危(wei)險性(xing)(xing)比心(xin)(xin)(xin)(xin)室(shi)晚(wan)電(dian)(dian)位陰性(xing)(xing)者高3.3倍。
臨床上須與暈厥、癔癥或癲癇相鑒別。
(1)心(xin)(xin)(xin)臟(zang)(zang)性(xing)(xing)猝死(si)的(de)(de)(de)緊急治療:①心(xin)(xin)(xin)肺(fei)復蘇(CPR)。早期(qi)、有(you)效的(de)(de)(de)措施(shi)至關重要(yao)(具體措施(shi)請參閱心(xin)(xin)(xin)肺(fei)復蘇)。②進一(yi)步的(de)(de)(de)心(xin)(xin)(xin)臟(zang)(zang)生命支持(ACLS)。早期(qi)除顫(zhan)(zhan)對改善存(cun)活至關重要(yao)。大約40%心(xin)(xin)(xin)臟(zang)(zang)性(xing)(xing)猝死(si)患(huan)者在醫務人員(yuan)到達時發(fa)現(xian)有(you)心(xin)(xin)(xin)室顫(zhan)(zhan)動。目前(qian)至少有(you)兩個(ge)正在進行的(de)(de)(de)前(qian)瞻性(xing)(xing)隨機臨床實(shi)驗(yan),研究胺碘酮在院外心(xin)(xin)(xin)臟(zang)(zang)性(xing)(xing)猝死(si)患(huan)者對電擊難治性(xing)(xing)心(xin)(xin)(xin)室顫(zhan)(zhan)動中的(de)(de)(de)作用。有(you)一(yi)個(ge)實(shi)驗(yan)的(de)(de)(de)初步結果提示胺碘酮是這(zhe)類患(huan)者急診治療的(de)(de)(de)有(you)效藥物。
(2)心臟性猝死的預防(fang)性治(zhi)療
一級預防治療:
可聯合使用心臟性猝死的多(duo)種預(yu)測因素(su)。
鑒(jian)于大多數(shu)(shu)心臟性(xing)猝(cu)死(si)(si)(si)發(fa)生在(zai)冠心病(bing)(bing)的(de)(de)(de)患者,減輕心肌缺血,預防心肌梗(geng)(geng)死(si)(si)(si)或縮小梗(geng)(geng)死(si)(si)(si)范圍,改變心肌梗(geng)(geng)死(si)(si)(si)后(hou)心室重構的(de)(de)(de)藥物應能減少(shao)(shao)心臟性(xing)猝(cu)死(si)(si)(si)的(de)(de)(de)發(fa)生率。早期研究(jiu)顯(xian)示與藥物治療(liao)相比,外(wai)科血管重建(jian),使3支血管病(bing)(bing)變及左心室功能不全的(de)(de)(de)冠心病(bing)(bing)患者的(de)(de)(de)心臟性(xing)猝(cu)死(si)(si)(si)下降。最近的(de)(de)(de)研究(jiu)顯(xian)示,應用(yong)溶栓藥和(或)經(jing)皮介入治療(liao)可獲得心肌再灌(guan)注和血管重建(jian)。已有(you)研究(jiu)證實β-阻滯劑(ji)在(zai)預防心肌梗(geng)(geng)死(si)(si)(si)存(cun)活者心臟性(xing)猝(cu)死(si)(si)(si)及降低其總死(si)(si)(si)亡(wang)率方面是有(you)效(xiao)的(de)(de)(de)。血管緊張素轉換(huan)酶(mei)抑制(zhi)劑(ji)(ACEI)在(zai)這方面的(de)(de)(de)證據(ju)要(yao)少(shao)(shao)一些,但有(you)少(shao)(shao)數(shu)(shu)研究(jiu)提示,血管緊張素轉換(huan)酶(mei)抑制(zhi)劑(ji)(ACEI)使左心室功能不全的(de)(de)(de)患者的(de)(de)(de)心臟性(xing)猝(cu)死(si)(si)(si)減少(shao)(shao)。
已有幾個隨機試(shi)驗(yan)開始實施,以比(bi)較ICD和藥(yao)物對心(xin)(xin)臟性(xing)(xing)猝死(si)一級(ji)預防(fang)的(de)(de)效果。在(zai)多中(zhong)心(xin)(xin)自(zi)動(dong)心(xin)(xin)臟復(fu)律(lv)(lv)除(chu)顫(zhan)器植(zhi)入(ru)(ru)試(shi)驗(yan)(MADIT)中(zhong),對非持續性(xing)(xing)室性(xing)(xing)心(xin)(xin)動(dong)過(guo)速、心(xin)(xin)肌梗死(si)后左室功能差以及電(dian)生理檢查時(shi)可誘發(fa)出用普魯卡(ka)因胺不(bu)能抑制(zhi)的(de)(de)室性(xing)(xing)心(xin)(xin)動(dong)過(guo)速患者(zhe),ICD比(bi)常規抗心(xin)(xin)律(lv)(lv)失常藥(yao)物更有效。但最近(jin)報道的(de)(de)冠狀(zhuang)動(dong)脈旁路(lu)移植(zhi)(CABG)補片試(shi)驗(yan)(patch trail)證(zheng)明給(gei)伴左室功能不(bu)全和信號平(ping)均心(xin)(xin)電(dian)圖異常的(de)(de)患者(zhe)做(zuo)CABG時(shi),預防(fang)性(xing)(xing)植(zhi)入(ru)(ru)ICD,并(bing)不(bu)能改(gai)善存活。
二級預防治療:
①抗心律(lv)失常藥:
心(xin)臟性猝(cu)死的(de)發生(sheng)機制主要是心(xin)室(shi)顫動,從理論上(shang)講(jiang),使用(yong)抗心(xin)律(lv)失常(chang)(chang)藥物控制或(huo)消除各種室(shi)性心(xin)律(lv)失常(chang)(chang)具有防治心(xin)臟性猝(cu)死的(de)作用(yong),但(dan)是,不(bu)同抗心(xin)律(lv)失常(chang)(chang)藥物的(de)臨床使用(yong)結果卻(que)不(bu)盡相同。
Ⅰ類抗心(xin)律失常藥物一度使(shi)(shi)用十分廣(guang)泛,但到目前為止,一些大規模隨機臨床試驗的(de)(de)結果表明,許多Ⅰ類抗心(xin)律失常藥物的(de)(de)使(shi)(shi)用并(bing)不能降(jiang)低心(xin)臟(zang)性(xing)猝死的(de)(de)發生率(lv),相(xiang)反卻使(shi)(shi)心(xin)臟(zang)性(xing)猝死的(de)(de)發生率(lv)升高(gao),其中,比較典型的(de)(de)是CAST。
CAST即心(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)抑(yi)制實驗(yan)(Cardiac arrhythmic suppression trial,CAST),是一(yi)項由美國(guo)國(guo)立(li)心(xin)(xin)(xin)(xin)(xin)肺血液研究組織的(de)(de)(de)隨(sui)機、雙盲對(dui)照(zhao)的(de)(de)(de)多中心(xin)(xin)(xin)(xin)(xin)臨床(chuang)試驗(yan)。旨在確定抗心(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)(yao)物(wu)抑(yi)制心(xin)(xin)(xin)(xin)(xin)肌(ji)梗(geng)死(si)(si)(si)后(hou)無癥(zheng)狀(zhuang)或伴有輕度(du)癥(zheng)狀(zhuang)的(de)(de)(de)室性(xing)心(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang),并了解能(neng)否降(jiang)(jiang)低(di)心(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)所致(zhi)的(de)(de)(de)病死(si)(si)(si)率。1989年報道的(de)(de)(de)CASTⅠ結果(guo)發表(biao)在《新英格蘭(lan)醫院(yuan)學(xue)雜志》第321卷上。這些研究結果(guo)表(biao)明,Ⅰc類抗心(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)(yao)物(wu)不僅不能(neng)降(jiang)(jiang)低(di)心(xin)(xin)(xin)(xin)(xin)肌(ji)梗(geng)死(si)(si)(si)后(hou)心(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)的(de)(de)(de)發生(sheng)率,相反卻可使患(huan)者的(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)臟(zang)猝死(si)(si)(si)率增加。其原因可能(neng)與下列2個因素有關,一(yi)是Ⅰ類抗心(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)(yao)物(wu)本身具有促心(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)作用;二是Ⅰc類抗心(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)(yao)物(wu)具有不同(tong)程度(du)的(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)肌(ji)抑(yi)制作用,可使患(huan)者的(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)功能(neng)進(jin)一(yi)步減退,射血分數進(jin)一(yi)步降(jiang)(jiang)低(di)。但是,CAST僅僅是在心(xin)(xin)(xin)(xin)(xin)肌(ji)梗(geng)死(si)(si)(si)后(hou)的(de)(de)(de)室性(xing)心(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)患(huan)者中進(jin)行(xing)的(de)(de)(de),在非(fei)心(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)的(de)(de)(de)患(huan)者發生(sheng)的(de)(de)(de)室性(xing)心(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)中,Ⅰc類抗心(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)(yao)物(wu)能(neng)否降(jiang)(jiang)低(di)心(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)猝死(si)(si)(si)的(de)(de)(de)發生(sheng)率,目前尚不清楚。
在(zai)(zai)抗(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)藥物(wu)(wu)中,目前Ⅲ類抗(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)藥物(wu)(wu)是(shi)最(zui)受推崇的(de)(de)(de)(de)(de)(de)(de),其原因(yin)是(shi)這些(xie)藥物(wu)(wu)不(bu)僅能有(you)(you)效控制各(ge)種(zhong)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang),而(er)且一些(xie)多中心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)隨(sui)機臨床試(shi)驗(yan)結(jie)果(guo)表(biao)明(ming)胺(an)碘(dian)(dian)(dian)(dian)(dian)酮(tong)(tong)(tong)(tong)(tong)(tong),長期口服(fu)時能增(zeng)加(jia)各(ge)種(zhong)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌組(zu)(zu)(zu)(zu)織的(de)(de)(de)(de)(de)(de)(de)動(dong)(dong)作(zuo)(zuo)(zuo)電位時程(cheng)和(he)(he)有(you)(you)效不(bu)應期,對(dui)各(ge)種(zhong)室(shi)(shi)上(shang)(shang)(shang)性(xing)(xing)(xing)(xing)(xing)和(he)(he)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang),包括心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)房(fang)(fang)顫動(dong)(dong)、心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)房(fang)(fang)撲動(dong)(dong)和(he)(he)室(shi)(shi)上(shang)(shang)(shang)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)(dong)過(guo)速(su)等都有(you)(you)較(jiao)好的(de)(de)(de)(de)(de)(de)(de)效果(guo)。口服(fu)劑量為(wei)(wei)200~800mg/d,,胺(an)碘(dian)(dian)(dian)(dian)(dian)酮(tong)(tong)(tong)(tong)(tong)(tong)除(chu)了(le)Ⅲ類抗(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)藥物(wu)(wu)的(de)(de)(de)(de)(de)(de)(de)特性(xing)(xing)(xing)(xing)(xing)外(wai)(wai),還(huan)有(you)(you)Ⅰ類抗(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)藥物(wu)(wu)作(zuo)(zuo)(zuo)用(yong)(yong)(yong),表(biao)現(xian)(xian)為(wei)(wei)使用(yong)(yong)(yong)依賴(lai)性(xing)(xing)(xing)(xing)(xing)動(dong)(dong)力(li)學特征(zheng),并具(ju)有(you)(you)一定(ding)的(de)(de)(de)(de)(de)(de)(de)阻滯(zhi)作(zuo)(zuo)(zuo)用(yong)(yong)(yong)和(he)(he)鈣(gai)通道阻滯(zhi)作(zuo)(zuo)(zuo)用(yong)(yong)(yong),其主要代謝產(chan)物(wu)(wu)脫乙基(ji)胺(an)腆(tian)(tian)酮(tong)(tong)(tong)(tong)(tong)(tong)仍(reng)具(ju)有(you)(you)抗(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)作(zuo)(zuo)(zuo)用(yong)(yong)(yong)。胺(an)腆(tian)(tian)酮(tong)(tong)(tong)(tong)(tong)(tong)和(he)(he)Ⅰc類抗(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)藥物(wu)(wu)不(bu)同,除(chu)了(le)發揮(hui)抗(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)作(zuo)(zuo)(zuo)用(yong)(yong)(yong)之外(wai)(wai),還(huan)有(you)(you)冠狀動(dong)(dong)脈擴張作(zuo)(zuo)(zuo)用(yong)(yong)(yong)、抗(kang)交感(gan)神經的(de)(de)(de)(de)(de)(de)(de)激活作(zuo)(zuo)(zuo)用(yong)(yong)(yong)和(he)(he)抗(kang)甲狀腺作(zuo)(zuo)(zuo)用(yong)(yong)(yong)。近(jin)年來,一些(xie)研究(jiu)發現(xian)(xian)胺(an)碘(dian)(dian)(dian)(dian)(dian)酮(tong)(tong)(tong)(tong)(tong)(tong)還(huan)有(you)(you)抗(kang)氧化作(zuo)(zuo)(zuo)用(yong)(yong)(yong)和(he)(he)拮抗(kang)鈣(gai)調節蛋白的(de)(de)(de)(de)(de)(de)(de)作(zuo)(zuo)(zuo)用(yong)(yong)(yong)。在(zai)(zai)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌缺血時,胺(an)腆(tian)(tian)酮(tong)(tong)(tong)(tong)(tong)(tong)能保護線粒體的(de)(de)(de)(de)(de)(de)(de)完(wan)整性(xing)(xing)(xing)(xing)(xing)和(he)(he)高(gao)能磷(lin)酸鹽的(de)(de)(de)(de)(de)(de)(de)功(gong)能。因(yin)此,從(cong)理論上(shang)(shang)(shang)講,胺(an)碘(dian)(dian)(dian)(dian)(dian)酮(tong)(tong)(tong)(tong)(tong)(tong)在(zai)(zai)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)的(de)(de)(de)(de)(de)(de)(de)防治(zhi)(zhi)(zhi)(zhi)中具(ju)有(you)(you)自己獨(du)特的(de)(de)(de)(de)(de)(de)(de)治(zhi)(zhi)(zhi)(zhi)療(liao)(liao)(liao)價值。“巴塞爾心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌梗(geng)(geng)(geng)幸存者(zhe)(zhe)(zhe)的(de)(de)(de)(de)(de)(de)(de)抗(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)研究(jiu)(Basel antiarrhythmic study of infarction survival,BASIS)”在(zai)(zai)臨床實踐中提示(shi)胺(an)碘(dian)(dian)(dian)(dian)(dian)酮(tong)(tong)(tong)(tong)(tong)(tong)在(zai)(zai)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝死(si)防治(zhi)(zhi)(zhi)(zhi)中的(de)(de)(de)(de)(de)(de)(de)價值。BASIS由(you)瑞士學者(zhe)(zhe)(zhe)完(wan)成,入選(xuan)病例為(wei)(wei)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌梗(geng)(geng)(geng)死(si)后(hou)(hou)8~24天并伴有(you)(you)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)期前收縮在(zai)(zai)Lown氏分級4~6級的(de)(de)(de)(de)(de)(de)(de)患(huan)(huan)(huan)者(zhe)(zhe)(zhe)。321例患(huan)(huan)(huan)者(zhe)(zhe)(zhe)被隨(sui)機分為(wei)(wei)2組(zu)(zu)(zu)(zu),分別用(yong)(yong)(yong)安(an)(an)慰劑、胺(an)碘(dian)(dian)(dian)(dian)(dian)酮(tong)(tong)(tong)(tong)(tong)(tong)和(he)(he)其他(ta)抗(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)藥物(wu)(wu)治(zhi)(zhi)(zhi)(zhi)療(liao)(liao)(liao),結(jie)果(guo)胺(an)腆(tian)(tian)酮(tong)(tong)(tong)(tong)(tong)(tong)治(zhi)(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)(zu)的(de)(de)(de)(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝死(si)率為(wei)(wei)5%,顯(xian)著低于安(an)(an)慰劑治(zhi)(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)(zu)的(de)(de)(de)(de)(de)(de)(de)11.4%t和(he)(he)其他(ta)抗(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)藥物(wu)(wu)治(zhi)(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)(zu)的(de)(de)(de)(de)(de)(de)(de)9%。此外(wai)(wai),另外(wai)(wai)兩項大(da)規模隨(sui)機臨床試(shi)驗(yan)“加(jia)拿大(da)胺(an)碘(dian)(dian)(dian)(dian)(dian)酮(tong)(tong)(tong)(tong)(tong)(tong)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌梗(geng)(geng)(geng)死(si)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)試(shi)驗(yan)(Canadian amiodarone myocardial infarction arrhythmia trial,CAMIAT)”和(he)(he)歐洲心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌梗(geng)(geng)(geng)死(si)胺(an)碘(dian)(dian)(dian)(dian)(dian)酮(tong)(tong)(tong)(tong)(tong)(tong)試(shi)驗(yan)“European myocardial infarction amiodarone trial,EMIAT)”正在(zai)(zai)進行,最(zui)后(hou)(hou)結(jie)果(guo)尚未揭曉。CAMLAT有(you)(you)21個醫學中心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)參加(jia),計劃入選(xuan)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌梗(geng)(geng)(geng)死(si)后(hou)(hou)6~45天伴室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)期前收縮10次/h以(yi)上(shang)(shang)(shang)或室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)(dong)過(guo)速(su)1次以(yi)上(shang)(shang)(shang)的(de)(de)(de)(de)(de)(de)(de)患(huan)(huan)(huan)者(zhe)(zhe)(zhe),隨(sui)機分為(wei)(wei)胺(an)碘(dian)(dian)(dian)(dian)(dian)酮(tong)(tong)(tong)(tong)(tong)(tong)治(zhi)(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)(zu)和(he)(he)安(an)(an)慰劑治(zhi)(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)(zu),預(yu)試(shi)完(wan)成77例,20個月的(de)(de)(de)(de)(de)(de)(de)觀(guan)察表(biao)明(ming),胺(an)碘(dian)(dian)(dian)(dian)(dian)酮(tong)(tong)(tong)(tong)(tong)(tong)治(zhi)(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)(zu)的(de)(de)(de)(de)(de)(de)(de)病死(si)率4%而(er)安(an)(an)慰劑治(zhi)(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)(zu)的(de)(de)(de)(de)(de)(de)(de)病死(si)率14%。EMIAT由(you)61個醫學中心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)參加(jia),計劃入選(xuan)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌梗(geng)(geng)(geng)死(si)后(hou)(hou)5~21天、左心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)射(she)血分數(shu)在(zai)(zai)40%以(yi)下的(de)(de)(de)(de)(de)(de)(de)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)患(huan)(huan)(huan)者(zhe)(zhe)(zhe),隨(sui)機分為(wei)(wei)安(an)(an)慰劑治(zhi)(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)(zu)和(he)(he)胺(an)碘(dian)(dian)(dian)(dian)(dian)酮(tong)(tong)(tong)(tong)(tong)(tong)治(zhi)(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)(zu)。中期結(jie)果(guo)表(biao)明(ming),胺(an)腆(tian)(tian)酮(tong)(tong)(tong)(tong)(tong)(tong)可顯(xian)著降(jiang)低心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌梗(geng)(geng)(geng)死(si)后(hou)(hou)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)(shi)(shi)(shi)(shi)常(chang)(chang)(chang)患(huan)(huan)(huan)者(zhe)(zhe)(zhe)的(de)(de)(de)(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)(xing)猝死(si)率。
索他(ta)洛(luo)爾(er)(sotalol)與胺碘酮相(xiang)似,也具有(you)混合性抗心(xin)(xin)律(lv)失常(chang)作用。許多學(xue)者的臨床觀察表(biao)明,索他(ta)洛(luo)爾(er)對心(xin)(xin)律(lv)失常(chang)患者的生存(cun)有(you)益,但(dan)還缺乏長期多中心(xin)(xin)臨床試驗的結果(guo)。
②β-腎上(shang)腺素受(shou)體(ti)(ti)(ti)阻滯(zhi)藥(yao):β-腎上(shang)腺能(neng)受(shou)體(ti)(ti)(ti)阻滯(zhi)藥(yao)的作用在于競爭心臟(zang),血管(guan)和支氣管(guan)等組織器官(guan)β腎上(shang)的腺素能(neng)受(shou)體(ti)(ti)(ti),使(shi)受(shou)體(ti)(ti)(ti)不能(neng)恢復到高親和力狀態而(er)與(yu)激動劑結合,從而(er)抑制β腎上(shang)腺素能(neng)受(shou)體(ti)(ti)(ti)的活性而(er)發揮(hui)一系列的藥(yao)理作用。
β受體(ti)阻(zu)滯藥在心臟性猝(cu)(cu)死中(zhong)的應用價值仍(reng)有爭議(yi),但(dan)多數學(xue)者認為(wei)在一些心臟的某一亞組可使心臟性猝(cu)(cu)死的發生率降(jiang)低。
到目(mu)前為止,已有(you)大量的研究(jiu)提(ti)示,心(xin)(xin)(xin)肌(ji)梗(geng)死(si)后的患者接受β受體阻滯劑治療非(fei)常有(you)益,特別是在(zai)降(jiang)低(di)心(xin)(xin)(xin)臟性猝死(si)方面有(you)較顯(xian)著的意義,并且還有(you)人(ren)發現,在(zai)一定范圍內(nei)心(xin)(xin)(xin)率降(jiang)得越慢效果越明顯(xian)。已有(you)2項多中心(xin)(xin)(xin)隨(sui)機臨床(chuang)試驗-(MIAMI)和(ISIS-I)觀察了(le)β受體阻滯劑在(zai)胸(xiong)痛(tong)(tong)發作(zuo)(zuo)12~24h內(nei)早期干預的作(zuo)(zuo)用(yong)(yong)。MIAMI入選(xuan)胸(xiong)痛(tong)(tong)發作(zuo)(zuo)24h以內(nei)的心(xin)(xin)(xin)肌(ji)梗(geng)死(si)患者5778例,首先使(shi)(shi)用(yong)(yong)美托洛爾15mg靜脈(mo)注射(she),然(ran)后200mg/d口服,1周(zhou)(zhou)病死(si)率下(xia)降(jiang)13%。ISIS-I入選(xuan)胸(xiong)痛(tong)(tong)發作(zuo)(zuo)12h內(nei)的心(xin)(xin)(xin)肌(ji)梗(geng)死(si)患者16000例,首先靜脈(mo)注射(she)阿替洛爾5~10mg,然(ran)后每(mei)周(zhou)(zhou)口服100mg,1周(zhou)(zhou)內(nei)心(xin)(xin)(xin)血管(guan)病死(si)率下(xia)降(jiang)15%。β-受體阻滯藥(yao)的作(zuo)(zuo)用(yong)(yong)主要(yao)是降(jiang)低(di)了(le)心(xin)(xin)(xin)室顫動或心(xin)(xin)(xin)臟破裂的發生率。在(zai)心(xin)(xin)(xin)肌(ji)梗(geng)死(si)的后期,使(shi)(shi)用(yong)(yong)β-受體阻滯藥(yao)可使(shi)(shi)心(xin)(xin)(xin)血管(guan)總(zong)病死(si)率降(jiang)低(di)20%~25%,但對心(xin)(xin)(xin)臟性猝死(si)發生率的影響尚不(bu)清楚。
在高血(xue)(xue)壓患者中(zhong),β-受(shou)(shou)體(ti)(ti)阻(zu)(zu)滯藥治療(liao)也對心臟(zang)性(xing)(xing)(xing)(xing)猝死具有(you)(you)(you)防治作用。但(dan)更多的(de)(de)(de)學者認為,只有(you)(you)(you)脂(zhi)(zhi)溶(rong)性(xing)(xing)(xing)(xing)的(de)(de)(de)β-受(shou)(shou)體(ti)(ti)阻(zu)(zu)滯藥如美托(tuo)洛(luo)爾才(cai)能有(you)(you)(you)效地降低心臟(zang)性(xing)(xing)(xing)(xing)猝死的(de)(de)(de)發生率。脂(zhi)(zhi)溶(rong)性(xing)(xing)(xing)(xing)β-受(shou)(shou)體(ti)(ti)阻(zu)(zu)滯藥在消化道易(yi)于吸收(shou),易(yi)于通過血(xue)(xue)腦屏障,在中(zhong)樞神經(jing)系統(tong)可以達到(dao)較高的(de)(de)(de)血(xue)(xue)藥濃度。一些小樣本研(yan)究(jiu)提示,選擇性(xing)(xing)(xing)(xing)β-受(shou)(shou)體(ti)(ti)阻(zu)(zu)滯藥美托(tuo)洛(luo)爾和阿替爾對心臟(zang)性(xing)(xing)(xing)(xing)猝死的(de)(de)(de)防治有(you)(you)(you)效。
③正(zheng)性肌力藥(yao)物(wu):
在充血性(xing)心力衰(shuai)竭(jie)患(huan)(huan)者中(zhong),心臟(zang)性(xing)猝(cu)死(si)(si)的(de)發(fa)生很高。1993年,Goldman等(deng)報道,冠(guan)心病引(yin)起的(de)充血性(xing)心力衰(shuai)竭(jie)患(huan)(huan)者中(zhong)44%死(si)(si)于心臟(zang)性(xing)猝(cu)死(si)(si);非(fei)冠(guan)心病引(yin)起的(de)充血性(xing)心力衰(shuai)竭(jie)患(huan)(huan)者中(zhong),心臟(zang)性(xing)猝(cu)死(si)(si)的(de)發(fa)生率為48%。因(yin)此,正性(xing)肌力藥(yao)物在心臟(zang)性(xing)猝(cu)死(si)(si)防(fang)治中(zhong)的(de)價值受(shou)到人(ren)們的(de)關(guan)注。
正(zheng)性(xing)肌力藥物主要包括兩類,即洋地黃類藥物和(he)cAMP依賴性(xing)強心劑。
洋(yang)(yang)地黃類藥(yao)物(wu)仍(reng)是(shi)目(mu)前治療心(xin)力(li)(li)(li)衰(shuai)(shuai)竭的(de)(de)(de)(de)基本藥(yao)物(wu)。近年來(lai)的(de)(de)(de)(de)研究表(biao)明(ming),洋(yang)(yang)地黃類藥(yao)物(wu)不(bu)(bu)僅能(neng)增強心(xin)肌收縮力(li)(li)(li)、減(jian)慢心(xin)率和(he)傳導,而且具有神經內分泌調節作用,可改善心(xin)力(li)(li)(li)衰(shuai)(shuai)竭患(huan)者的(de)(de)(de)(de)壓力(li)(li)(li)感受器(qi)功(gong)能(neng)低(di)(di)下和(he)交感神經系(xi)(xi)統(tong)、腎素(su)-血管(guan)緊張素(su)-醛固酮系(xi)(xi)統(tong)的(de)(de)(de)(de)功(gong)能(neng)亢進,并可提高(gao)(gao)心(xin)鈉素(su)的(de)(de)(de)(de)分泌,降低(di)(di)心(xin)臟(zang)前負荷。盡(jin)管(guan)洋(yang)(yang)地黃的(de)(de)(de)(de)應用已有200多(duo)年的(de)(de)(de)(de)歷史,但他在充血性(xing)(xing)心(xin)力(li)(li)(li)衰(shuai)(shuai)竭治療中是(shi)否能(neng)降低(di)(di)心(xin)臟(zang)性(xing)(xing)猝死(si)的(de)(de)(de)(de)發生率仍(reng)不(bu)(bu)十分清楚。1998年以(yi)來(lai),已有幾項大規(gui)模隨機臨床(chuang)試(shi)驗結果可直接或間(jian)接反映(ying)地高(gao)(gao)辛(xin)治療心(xin)力(li)(li)(li)衰(shuai)(shuai)竭是(shi)有效(xiao)的(de)(de)(de)(de),不(bu)(bu)僅能(neng)改善充血性(xing)(xing)心(xin)力(li)(li)(li)衰(shuai)(shuai)竭的(de)(de)(de)(de)癥狀,而且可以(yi)提高(gao)(gao)患(huan)者的(de)(de)(de)(de)運動量和(he)心(xin)功(gong)能(neng),但均(jun)未闡明(ming)地高(gao)(gao)辛(xin)對心(xin)臟(zang)性(xing)(xing)猝死(si)的(de)(de)(de)(de)防治作用。
CAMP依賴性強心(xin)劑包括(kuo):受體激動劑和磷(lin)酸二酯酶Ⅲ抑制劑。前者(zhe)主(zhu)要(yao)多巴酚丁(ding)胺、沙丁(ding)胺醇(chun)等;后者(zhe)包括(kuo)氨力(li)農(nong)。米(mi)力(li)農(nong)。臨床實踐的(de)(de)(de)結(jie)果表明,cAMP依賴性強心(xin)劑在增(zeng)強心(xin)肌收縮(suo)力(li)和改善患者(zhe)的(de)(de)(de)癥狀方面(mian)具有一度(du)的(de)(de)(de)療(liao)效(xiao),但口服(fu)(fu)給藥(yao)的(de)(de)(de)不良反應較多,而且可增(zeng)加心(xin)臟性猝死的(de)(de)(de)發生率。因此(ci),氨力(li)農(nong)和米(mi)力(li)農(nong)等藥(yao)物的(de)(de)(de)口服(fu)(fu)給藥(yao)已經禁止采用。
④抗血小板藥:
A.臨(lin)床常(chang)用(yong)的抗血(xue)小板藥物(wu)及其作用(yong)原理:
抗血(xue)小(xiao)(xiao)板(ban)藥物是指能阻礙血(xue)小(xiao)(xiao)板(ban)黏附、聚集和釋放反應(ying),以(yi)防止血(xue)栓形(xing)成的(de)藥物。根據作用(yong)的(de)環節,常用(yong)的(de)抗血(xue)小(xiao)(xiao)板(ban)藥物包括以(yi)下幾類:
a.環氧(yang)化酶抑制藥:
包括(kuo)阿司匹(pi)林(lin)(aspirin)、磺吡酮(tong)(tong)(苯磺唑酮(tong)(tong))等(deng)。阿司匹(pi)林(lin)是一種非甾體抗炎藥(yao)(yao),1971年發(fa)現它有抑制環氧化酶的作用(yong),目前(qian)已(yi)成為最常用(yong)的抗血小板(ban)藥(yao)(yao)物。
花生四烯酸(suan)在環氧化酶(mei)(即前(qian)(qian)列(lie)腺(xian)素合成酶(mei))的作用(yong)下(xia)形成不(bu)穩(wen)定(ding)的環內(nei)過(guo)氧化物(wu)(wu),即前(qian)(qian)列(lie)腺(xian)素C2(PGG2)和(he)前(qian)(qian)列(lie)腺(xian)素H2(PGH2)。環內(nei)過(guo)氧化物(wu)(wu)在血(xue)(xue)(xue)小板微粒體(ti)中血(xue)(xue)(xue)栓烷合酶(mei)的作用(yong)下(xia)生成血(xue)(xue)(xue)栓素A2(TXA2),但TXA2不(bu)穩(wen)定(ding),半衰期(qi)為(wei)30s,迅速轉變為(wei)穩(wen)定(ding)的TXB2。在血(xue)(xue)(xue)管壁微粒體(ti)中,環內(nei)過(guo)氧化物(wu)(wu)在6(9)-環氧化酶(mei)作用(yong)下(xia)合成前(qian)(qian)列(lie)腺(xian)素I2(PGl2),然后代謝為(wei)6-酮-PGFla。TAX2使(shi)血(xue)(xue)(xue)管收(shou)縮(suo),降低(di)血(xue)(xue)(xue)小板cAMP,促進血(xue)(xue)(xue)小板聚集和(he)血(xue)(xue)(xue)栓形成。
阿司匹(pi)林(lin)主(zhu)要抑制環氧化(hua)酶,使(shi)其活性基團乙酰化(hua),從而阻止(zhi)TXA2和PGI2的(de)生成。由于阿司匹(pi)林(lin)在(zai)抑制TXB2的(de)同時,也(ye)對(dui)PGI2造成了(le)抑制,則阿司匹(pi)林(lin)使(shi)用的(de)有益(yi)作(zuo)(zuo)用被(bei)削(xue)弱(ruo)或(huo)抵消。大(da)量研究表明(ming),75~325mg/d的(de)阿司匹(pi)林(lin)給藥對(dui)PGI2的(de)影響較弱(ruo)或(huo)幾乎沒(mei)有影響,而對(dui)TXB2的(de)仍有明(ming)顯的(de)抑制作(zuo)(zuo)用。
磺吡酮(苯磺唑酮)是保太松(song)類藥物的(de)衍生物,1950年被用于治(zhi)療(liao)痛風,1965年發(fa)現它對(dui)血(xue)小(xiao)板(ban)功(gong)能(neng)具有(you)明顯影(ying)響(xiang)(xiang)。現已知道,主要抑制(zhi)血(xue)小(xiao)板(ban)的(de)環氧(yang)化酶而抑制(zhi)TXA2的(de)合成(cheng)(cheng),并可抑制(zhi)血(xue)小(xiao)板(ban)的(de)聚集和釋放反應。對(dui)血(xue)管內(nei)皮(pi)細胞合成(cheng)(cheng)的(de)PGI2影(ying)響(xiang)(xiang)極小(xiao)。
b.磷酸(suan)二酯(zhi)酶抑制藥:
包括(kuo)雙嘧達莫(persantine)等。雙嘧達莫又叫潘(pan)(pan)生丁,是(shi)一種(zhong)廣泛(fan)應(ying)用于臨床的抗血(xue)(xue)小(xiao)(xiao)板藥物,其機制(zhi)是(shi)抑制(zhi)血(xue)(xue)小(xiao)(xiao)板的磷酸二(er)酯酶(mei),使血(xue)(xue)小(xiao)(xiao)板的cAMP含量升(sheng)高。同(tong)時(shi),雙嘧達莫(潘(pan)(pan)生丁)還(huan)可(ke)通(tong)過增加血(xue)(xue)液的腺(xian)苷(gan)濃(nong)度而抑制(zhi)血(xue)(xue)小(xiao)(xiao)板的聚集和(he)(he)釋放反(fan)應(ying)。潘(pan)(pan)生丁可(ke)抑制(zhi)紅細(xi)胞(bao)和(he)(he)心、肺等組織(zhi)細(xi)胞(bao)對血(xue)(xue)中腺(xian)苷(gan)的攝取。則(ze)腺(xian)苷(gan)不(bu)能(neng)被腺(xian)苷(gan)脫胺酶(mei)所破壞,血(xue)(xue)液中腺(xian)苷(gan)水(shui)平增加,一般口服(fu)給藥,每次400mg,1~2次/d。主要不(bu)良反(fan)應(ying)為(wei)胃腸道癥狀。
c.血栓(shuan)合成酶(mei)抑制(zhi)藥(yao):
包括水(shui)楊酸咪(mi)唑(zuo)(zuo)(咪(mi)唑(zuo)(zuo))、達唑(zuo)(zuo)氧苯(dazoxiben)、對乙酰氨基酚(APA)等。
d.腺苷酸環(huan)化酶激活劑(ji):
依前列(lie)(lie)醇(前列(lie)(lie)腺素(su)I2)和前列(lie)(lie)地爾(前列(lie)(lie)腺素(su)E1) 等(deng)。
e.其他:
噻(sai)氯(lv)匹定(ding)(噻(sai)氯(lv)吡啶)、舒洛地(di)爾(er)(suloctidil)等。
B.抗(kang)血小板(ban)藥物(wu)防治心臟性猝死的(de)價值:
在(zai)抗血小板藥物的(de)(de)(de)(de)研(yan)究中(zhong)(zhong),較多(duo)的(de)(de)(de)(de)資料為阿(a)司(si)匹(pi)(pi)林(lin)(lin)(lin)。許多(duo)研(yan)究表明,阿(a)司(si)匹(pi)(pi)林(lin)(lin)(lin)在(zai)穩定(ding)(ding)性(xing)(xing)和不穩定(ding)(ding)性(xing)(xing)心(xin)(xin)(xin)(xin)(xin)絞痛患(huan)者(zhe)中(zhong)(zhong)的(de)(de)(de)(de)應(ying)用(yong)(yong)(yong)后(hou),可(ke)顯著降低致死(si)(si)(si)性(xing)(xing)和非致死(si)(si)(si)性(xing)(xing)心(xin)(xin)(xin)(xin)(xin)肌梗死(si)(si)(si)的(de)(de)(de)(de)發(fa)生率(lv);在(zai)心(xin)(xin)(xin)(xin)(xin)肌梗死(si)(si)(si)患(huan)者(zhe)應(ying)用(yong)(yong)(yong)后(hou),可(ke)顯著降低再梗死(si)(si)(si)的(de)(de)(de)(de)發(fa)生率(lv)。但是,有關阿(a)司(si)匹(pi)(pi)林(lin)(lin)(lin)防治心(xin)(xin)(xin)(xin)(xin)臟(zang)病(bing)猝(cu)死(si)(si)(si)的(de)(de)(de)(de)價值,不同學者(zhe)的(de)(de)(de)(de)報道不盡一(yi)致。德國-奧地利(li)多(duo)中(zhong)(zhong)心(xin)(xin)(xin)(xin)(xin)研(yan)究結果提示,阿(a)司(si)匹(pi)(pi)林(lin)(lin)(lin)對(dui)心(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)(xing)猝(cu)死(si)(si)(si)的(de)(de)(de)(de)防治有一(yi)定(ding)(ding)作(zuo)用(yong)(yong)(yong)。Elwood等報道用(yong)(yong)(yong)阿(a)司(si)匹(pi)(pi)林(lin)(lin)(lin)治療心(xin)(xin)(xin)(xin)(xin)肌梗死(si)(si)(si)進行(xing)隨(sui)機、雙盲大宗病(bing)例研(yan)究的(de)(de)(de)(de)結果,發(fa)現在(zai)心(xin)(xin)(xin)(xin)(xin)肌梗死(si)(si)(si)后(hou)6周以內(nei)使用(yong)(yong)(yong)阿(a)司(si)匹(pi)(pi)林(lin)(lin)(lin)者(zhe),33個(ge)月隨(sui)訪期間(jian)的(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)(xing)猝(cu)死(si)(si)(si)率(lv)在(zai)阿(a)司(si)匹(pi)(pi)林(lin)(lin)(lin)組為7.8%、安慰劑組為13.5%,阿(a)司(si)匹(pi)(pi)林(lin)(lin)(lin)組心(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)(xing)猝(cu)死(si)(si)(si)的(de)(de)(de)(de)發(fa)生率(lv)降低了42%。如果阿(a)司(si)匹(pi)(pi)林(lin)(lin)(lin)的(de)(de)(de)(de)使用(yong)(yong)(yong)時間(jian)較晚則對(dui)心(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)(xing)猝(cu)死(si)(si)(si)的(de)(de)(de)(de)發(fa)生率(lv)無明顯作(zuo)用(yong)(yong)(yong)。
雙嘧達莫(潘(pan)生(sheng)(sheng)丁(ding)(ding))在心臟性猝死(si)防治中的評價(jia)研(yan)究多為(wei)與(yu)阿司匹林聯合(he)應用。雙嘧達莫(潘(pan)生(sheng)(sheng)丁(ding)(ding))和阿司匹林的再(zai)梗(geng)死(si)研(yan)究(PARIS)的結果(guo)提示,雙嘧達莫(潘(pan)生(sheng)(sheng)丁(ding)(ding))和阿司匹林合(he)用可降(jiang)低心肌梗(geng)死(si)后(hou)的總病(bing)死(si)率和心臟性猝死(si)發生(sheng)(sheng)率。
磺(huang)(huang)吡(bi)酮(tong)(苯(ben)磺(huang)(huang)唑酮(tong))在心臟性猝(cu)死(si)防治(zhi)中的價值研究(jiu)不多(duo)。美國磺(huang)(huang)吡(bi)酮(tong)(苯(ben)磺(huang)(huang)唑酮(tong))研究(jiu)組(zu)報道,在6個(ge)(ge)月(yue)內(nei),磺(huang)(huang)吡(bi)酮(tong)(苯(ben)磺(huang)(huang)唑酮(tong))可顯著降低心臟性猝(cu)死(si)的發(fa)生率;而在6個(ge)(ge)月(yue)后對心臟性猝(cu)死(si)的發(fa)生率無明顯影(ying)響。
⑤血管緊張素轉換酶抑制藥:
血(xue)(xue)管緊(jin)張素轉換酶抑(yi)制藥(angiotensin converting enzyme inhibitor,ACEI)是目前(qian)(qian)世界上發展最快(kuai)的(de)一類(lei)心血(xue)(xue)管藥物,目前(qian)(qian)在臨床上得到廣泛(fan)應用,許(xu)多(duo)研究發現,ACEI對心肌梗死(si)、高血(xue)(xue)壓和充血(xue)(xue)性心力衰竭等疾病可能并發的(de)心臟性猝死(si)具有一定的(de)防治作(zuo)用。
目(mu)前(qian),ACEI已發展到幾十(shi)種(zhong)(zhong)。根據(ju)其含(han)有(you)(you)(you)的(de)(de)基(ji)團(tuan)不(bu)同,ACEI可(ke)(ke)(ke)(ke)分為3種(zhong)(zhong)類型:A.含(han)巰(qiu)基(ji)的(de)(de)ACEI。主要有(you)(you)(you)卡托普利(li)(captopril);B.含(han)羥基(ji)的(de)(de)ACEI。主要有(you)(you)(you)依那(nei)普利(li)(enalapril)、雷米普利(li)(ramipril)、貝那(nei)普利(li)(苯拉普利(li))等(deng)。C.含(han)磷(lin)酰基(ji)的(de)(de)ACEI。主要有(you)(you)(you)福辛普利(li)(fosinopril)等(deng)。其基(ji)本作用(yong)機(ji)制(zhi)是抑制(zhi)血(xue)(xue)管(guan)(guan)緊(jin)張(zhang)(zhang)素(su)轉(zhuan)換酶(mei)(mei),血(xue)(xue)管(guan)(guan)緊(jin)張(zhang)(zhang)素(su)轉(zhuan)換酶(mei)(mei)是一(yi)種(zhong)(zhong)含(han)有(you)(you)(you)鋅離(li)子的(de)(de)金屬蛋白,各個活性部(bu)位(wei)都含(han)有(you)(you)(you)鋅離(li)子,ACEI的(de)(de)巰(qiu)基(ji)、羥基(ji)或磷(lin)酰基(ji)可(ke)(ke)(ke)(ke)與鋅離(li)子發生牢固(gu)的(de)(de)絡合作用(yong)而使血(xue)(xue)管(guan)(guan)緊(jin)張(zhang)(zhang)素(su)轉(zhuan)換酶(mei)(mei)失(shi)去活性。結果血(xue)(xue)管(guan)(guan)緊(jin)張(zhang)(zhang)素(su)Ⅰ不(bu)能(neng)轉(zhuan)變為血(xue)(xue)管(guan)(guan)緊(jin)張(zhang)(zhang)素(su)Ⅱ,可(ke)(ke)(ke)(ke)導致(zhi)血(xue)(xue)管(guan)(guan)擴張(zhang)(zhang)、醛固(gu)酮(tong)分泌減(jian)少(shao)(shao)和(he)交感神(shen)經張(zhang)(zhang)力降(jiang)低(di)。此外,ACEI還(huan)可(ke)(ke)(ke)(ke)抑制(zhi)激(ji)肽酶(mei)(mei),減(jian)慢緩(huan)激(ji)肽的(de)(de)降(jiang)解(jie),引起(qi)血(xue)(xue)管(guan)(guan)擴張(zhang)(zhang);同時,緩(huan)激(ji)肽的(de)(de)濃度增高(gao)可(ke)(ke)(ke)(ke)激(ji)活前(qian)磷(lin)脂酶(mei)(mei)而使前(qian)列(lie)腺素(su)的(de)(de)生成增加(jia)。ACEI還(huan)可(ke)(ke)(ke)(ke)減(jian)少(shao)(shao)鈣(gai)離(li)子內流(liu),使心(xin)肌細(xi)胞內鈣(gai)離(li)子超負荷而引起(qi)的(de)(de)心(xin)律失(shi)常減(jian)少(shao)(shao)。這些作用(yong)對于(yu)冠心(xin)病、高(gao)血(xue)(xue)壓病和(he)充(chong)血(xue)(xue)性心(xin)力衰(shuai)竭(jie)等(deng)具有(you)(you)(you)治療價值,還(huan)可(ke)(ke)(ke)(ke)增加(jia)心(xin)肌細(xi)胞電活動(dong)的(de)(de)穩(wen)定(ding)性。
⑥代謝類藥物:
曲美他嗪(萬爽(shuang)力),抑(yi)制心(xin)肌細(xi)(xi)胞線粒體內脂肪酸的(de)氧化,加(jia)速糖原酵解(jie),增加(jia)心(xin)肌細(xi)(xi)胞無氧代(dai)謝(xie)下ATP的(de)產生,增強心(xin)肌細(xi)(xi)胞的(de)抗缺血能(neng)力,從而可預(yu)防心(xin)臟性猝死的(de)發(fa)生。
埋藏式自動心(xin)(xin)臟復律(lv)(lv)除顫器(ICD)的應用是防治心(xin)(xin)臟性(xing)猝死的重要進展(zhan),對致(zhi)命性(xing)室(shi)性(xing)心(xin)(xin)律(lv)(lv)失常引起的心(xin)(xin)臟性(xing)猝死具有肯(ken)定的防治作用。
植入ICD的(de)(de)臨床價值在于(yu)有(you)效地防治心(xin)(xin)臟(zang)猝死。據文(wen)獻(xian)報(bao)道,美國每年(nian)因(yin)心(xin)(xin)臟(zang)驟(zou)停而(er)發生心(xin)(xin)臟(zang)性(xing)猝死的(de)(de)患(huan)(huan)者(zhe)達50萬人(ren)以上,歐洲約40萬人(ren)。其中75%~80%的(de)(de)患(huan)(huan)者(zhe)在第(di)1次心(xin)(xin)臟(zang)驟(zou)停發作時死亡(wang),經有(you)效心(xin)(xin)肺腦復蘇而(er)幸存者(zhe)中20%~25%的(de)(de)患(huan)(huan)者(zhe)可在1年(nian)內再次發生心(xin)(xin)臟(zang)驟(zou)停,因(yin)此(ci),ICD的(de)(de)應用范圍非常廣泛。
也有一些學者對植入ICD的(de)兩種不(bu)同方(fang)式進行了對比,結果(guo)發現(xian)經靜脈(mo)植入ICD的(de)圍術期(qi)病死率較低,長期(qi)隨(sui)訪的(de)存活率高(gao),應列為(wei)(wei)首選方(fang)法。Saksena等總(zong)結了221例多中心植入ICD的(de)結果(guo),開胸法植入ICD的(de)圍術期(qi)病死率為(wei)(wei)4.2%,經靜脈(mo)法為(wei)(wei)0.8%,隨(sui)訪2年的(de)總(zong)成活率分(fen)別(bie)為(wei)(wei)81.9%和87.6%,并(bing)無顯著性差異。
為了明(ming)確揭示埋(mai)藏(zang)式(shi)心(xin)(xin)(xin)(xin)臟復(fu)律(lv)除(chu)(chu)顫(zhan)器(qi)(qi)(qi)防(fang)治心(xin)(xin)(xin)(xin)臟猝死的價值,有學者(zhe)進行了一些多(duo)中(zhong)心(xin)(xin)(xin)(xin)隨機化前瞻性對(dui)照(zhao)研(yan)究。抗(kang)心(xin)(xin)(xin)(xin)律(lv)失常(chang)藥物(wu)與(yu)埋(mai)藏(zang)式(shi)心(xin)(xin)(xin)(xin)臟復(fu)律(lv)除(chu)(chu)顫(zhan)器(qi)(qi)(qi)對(dui)致(zhi)命性室性心(xin)(xin)(xin)(xin)律(lv)失常(chang)復(fu)蘇患(huan)者(zhe)治療(liao)比(bi)較研(yan)究(AVID)表明(ming),室顫(zhan)復(fu)蘇者(zhe)或有癥(zheng)狀和(he)血(xue)流動力學障礙的持續(xu)性室性心(xin)(xin)(xin)(xin)動過速(su)患(huan)者(zhe),應用埋(mai)藏(zang)式(shi)心(xin)(xin)(xin)(xin)臟復(fu)律(lv)除(chu)(chu)顫(zhan)器(qi)(qi)(qi)與(yu)抗(kang)心(xin)(xin)(xin)(xin)律(lv)失常(chang)藥物(wu)相比(bi),可明(ming)顯提高生(sheng)存率。其他一些多(duo)中(zhong)心(xin)(xin)(xin)(xin)試驗(yan)如多(duo)中(zhong)心(xin)(xin)(xin)(xin)自動除(chu)(chu)顫(zhan)器(qi)(qi)(qi)埋(mai)藏(zang)試驗(yan)(MADIT)、加拿(na)大埋(mai)藏(zang)式(shi)除(chu)(chu)顫(zhan)器(qi)(qi)(qi)研(yan)究(CIDS)、漢堡心(xin)(xin)(xin)(xin)臟驟停(ting)研(yan)究(CASH)、美(mei)國心(xin)(xin)(xin)(xin)、肺和(he)血(xue)液研(yan)究所(suo)埋(mai)藏(zang)式(shi)心(xin)(xin)(xin)(xin)臟復(fu)律(lv)除(chu)(chu)顫(zhan)器(qi)(qi)(qi)(NHLBHCD)等有的已經(jing)完成,有的正(zheng)在進行,最后將揭示ICD防(fang)治心(xin)(xin)(xin)(xin)臟性猝死的確切價值。
從心臟性猝死復蘇過來的幸運者在1年內發生致命性心律失常的復發率達25%~30%。已有試驗表明,ICD能有效轉復心臟性猝死患者的復發性心室顫動。Newman等對心臟驟停復蘇過來的幸存者進行了回顧性研究,60例患者植入ICD而120例患者僅僅使用藥物治療,兩組病例的年齡、左心室射血分數、心律失常類型、基礎心臟病和藥物治療情況相似。結果,ICD植入者的心臟性猝死率降低50%(10%∶5%,P<0.01),3年實際病死率降低31%(51%∶35%,P<0.01),5年的生存曲線也有明顯差異。但是,也必須注意,許多心臟性猝死幸存者(20%~70%)最后并不一定死于致命性心律失常,大約5%的心臟性猝死幸存者死于電-機械分離,而ICD對這種類型的心律失常無效。
①經導管射頻(pin)消(xiao)融(rong)治療(liao)室(shi)(shi)性(xing)心(xin)(xin)律(lv)失常(chang):室(shi)(shi)性(xing)心(xin)(xin)動(dong)過(guo)速(su)發(fa)(fa)作時常(chang)引起嚴重的血流動(dong)力學障礙(ai),心(xin)(xin)臟性(xing)猝死的發(fa)(fa)生率高。1988年,Davis首(shou)次使(shi)用射頻(pin)消(xiao)融(rong)治療(liao)室(shi)(shi)性(xing)心(xin)(xin)動(dong)過(guo)速(su)成功,開創射頻(pin)消(xiao)融(rong)的新領域,但至今仍不如室(shi)(shi)上(shang)性(xing)心(xin)(xin)動(dong)過(guo)速(su)使(shi)用普遍。室(shi)(shi)性(xing)心(xin)(xin)動(dong)過(guo)速(su)的消(xiao)融(rong),成功的關鍵之(zhi)一是(shi)心(xin)(xin)動(dong)過(guo)速(su)的起源定位,其方法(fa)是(shi)進(jin)行(xing)心(xin)(xin)內膜標(biao)測,一般(ban)根據Josephson提(ti)出的18個點標(biao)測,左(zuo)心(xin)(xin)室(shi)(shi)12,右(you)心(xin)(xin)室(shi)(shi)6個,標(biao)測方法(fa)有3種:
A.竇(dou)性心律時的標(biao)測:
在竇性心律下,在心室的不同部位尋找有明顯延遲碎裂電位的部位。延遲破裂電位是缺血區殘存心肌纖維的非同步除極,常常被大量結締組織所包繞,彼此連接較少,因此傳導很慢,形成緩慢傳導區,成為室性心動過速折返環的重要組成部分。在低倍放大條件下,延遲碎裂電位表現為高頻成分組成的低振幅波(<1mV),持續100ms以上。但必須注意,延遲破裂電位僅僅表示該部位有傳導延緩。并不表示一定為室性心動過速的起源部位,因此,竇性心律下的標測是不可靠的。
B.起搏標測:
用(yong)電(dian)極在心(xin)室(shi)的(de)不(bu)(bu)同(tong)部位作心(xin)內膜起搏(bo),起搏(bo)頻率與心(xin)動過速(su)的(de)頻率相(xiang)同(tong),記(ji)錄12導(dao)聯(lian)(lian)心(xin)電(dian)圖,若11個以上(shang)導(dao)聯(lian)(lian)的(de)圖形與心(xin)動過速(su)發作時的(de)相(xiang)同(tong),可認為該起搏(bo)部位即(ji)是心(xin)動過速(su)的(de)起源部位,但起搏(bo)標測(ce)也不(bu)(bu)可靠(kao)。
C.心動(dong)過速時的標測:
有心(xin)動過(guo)(guo)速發作時,在心(xin)室內不同(tong)部(bu)(bu)位記錄(lu)心(xin)內膜(mo)電圖,比較(jiao)哪(na)一部(bu)(bu)位的(de)心(xin)室激動時間比體表心(xin)電圖的(de)QRS波提前,則最早激動的(de)部(bu)(bu)位是(shi)心(xin)動過(guo)(guo)速的(de)起源點。心(xin)運過(guo)(guo)速的(de)標測是(shi)室性心(xin)動過(guo)(guo)速定位的(de)較(jiao)可靠(kao)方法。
準確定位后,行射頻消(xiao)融(rong)(rong),一(yi)般用30~40W,10~30s。成功的(de)(de)因素(su)(su)是:精確的(de)(de)起搏標測;最早(zao)的(de)(de)局部心(xin)(xin)室激(ji)動;導管(guan)電極(ji)與心(xin)(xin)內(nei)膜密(mi)切(qie)接觸(chu)。失(shi)敗的(de)(de)因素(su)(su)是:消(xiao)融(rong)(rong)電極(ji)未到達起源點(dian);導管(guan)電極(ji)與心(xin)(xin)內(nei)膜接觸(chu)不緊密(mi);室性心(xin)(xin)動過速(su)的(de)(de)起源點(dian)位于(yu)心(xin)(xin)肌內(nei)或心(xin)(xin)外膜。
不同類型的室(shi)速,消(xiao)(xiao)融(rong)(rong)的療效(xiao)(xiao)不同,其中,無(wu)器(qi)質心(xin)(xin)(xin)臟病的特發性(xing)室(shi)速,成功(gong)率達94%。束支折(zhe)(zhe)(zhe)返(fan)性(xing)心(xin)(xin)(xin)動(dong)過(guo)(guo)速,是由希氏-心(xin)(xin)(xin)肌傳導(dao)系(xi)統參與的大折(zhe)(zhe)(zhe)返(fan),消(xiao)(xiao)融(rong)(rong)右束即(ji)可(ke)(ke)終止室(shi)速,成功(gong)率超過(guo)(guo)90%。目前較(jiao)困(kun)難的是梗死后(hou)室(shi)性(xing)心(xin)(xin)(xin)動(dong)過(guo)(guo)速成功(gong)率不高(gao),一(yi)(yi)般在45%~93%,差異較(jiao)大,其原因在于梗死性(xing)心(xin)(xin)(xin)動(dong)過(guo)(guo)速的機制(zhi)較(jiao)復雜(za)所致(zhi)。梗死后(hou)室(shi)性(xing)心(xin)(xin)(xin)動(dong)過(guo)(guo)速的射(she)頻(pin)消(xiao)(xiao)融(rong)(rong),包括以下幾(ji)種情形:a.瘢(ban)痕(hen)(hen)周(zhou)(zhou)圍折(zhe)(zhe)(zhe)返(fan):必(bi)須在瘢(ban)痕(hen)(hen)組織周(zhou)(zhou)圍產生較(jiao)大損傷,折(zhe)(zhe)(zhe)返(fan)才(cai)能(neng)(neng)終止;b.瘢(ban)痕(hen)(hen)內折(zhe)(zhe)(zhe)返(fan):大部(bu)分病例可(ke)(ke)用射(she)頻(pin)消(xiao)(xiao)融(rong)(rong)成功(gong);c.功(gong)能(neng)(neng)性(xing)折(zhe)(zhe)(zhe)返(fan):射(she)頻(pin)消(xiao)(xiao)融(rong)(rong)常常無(wu)效(xiao)(xiao)。有時(shi),射(she)頻(pin)消(xiao)(xiao)融(rong)(rong)術后(hou)可(ke)(ke)在功(gong)能(neng)(neng)性(xing)上(shang)折(zhe)(zhe)(zhe)返(fan)的基礎上(shang),增加一(yi)(yi)個解剖性(xing)因素而產生更為頑固的折(zhe)(zhe)(zhe)返(fan)性(xing)心(xin)(xin)(xin)律(lv)失常。
②經皮球囊冠狀(zhuang)動脈(mo)成(cheng)形(xing)術(shu)治療冠心(xin)病。從理論上講,經皮球囊冠狀(zhuang)動脈(mo)形(xing)成(cheng)術(shu)治療冠心(xin)病應能有(you)效降低(di)心(xin)臟性猝死的發(fa)生率。當迄今(jin)未見到多中心(xin)隨機臨床(chuang)觀察資(zi)料。
①室性(xing)心律失常的外科治(zhi)療:
近10幾(ji)年(nian)來,用手術切割、冷凍或激光等手段可成功地控制(zhi)或根(gen)治室性(xing)心(xin)動(dong)過速/或心(xin)室顫動(dong),從(cong)而減少心(xin)臟性(xing)猝(cu)死(si)的發(fa)生率。
A.內(nei)膜(mo)病灶切除術(shu):
這種治療(liao)方法(fa)于1979年由Harken用(yong)于臨床,其方法(fa)是首先(xian)進(jin)行病灶(zao)定位。Harken等的(de)方法(fa)是在常(chang)溫體(ti)外(wai)循環下(xia),用(yong)手持移動電極在心(xin)(xin)(xin)內(nei)膜面(mian)進(jin)行標測(ce),找出最(zui)早(zao)心(xin)(xin)(xin)室(shi)激動部(bu)位,經左心(xin)(xin)(xin)室(shi)切(qie)口(kou)對(dui)標測(ce)出來的(de)最(zui)早(zao)心(xin)(xin)(xin)室(shi)激動部(bu)位作直徑2~3cm厚約數毫米的(de)盤狀(zhuang)切(qie)除(chu)。心(xin)(xin)(xin)內(nei)膜病灶(zao)切(qie)除(chu)術適用(yong)于病灶(zao)局限(xian),尤其適用(yong)于位于室(shi)壁瘤邊緣而遠離(li)心(xin)(xin)(xin)臟(zang)傳導(dao)系統(tong)和(he)乳頭肌的(de)病灶(zao)。
B.心(xin)內膜環形心(xin)室肌切(qie)除術(shu):
對于有(you)室(shi)壁瘤而伴發室(shi)性心(xin)(xin)動過速的(de)患者(zhe)可在室(shi)壁瘤邊緣的(de)正常心(xin)(xin)內膜(mo)作(zuo)弧形切(qie)口,深達心(xin)(xin)肌層(ceng)(ceng),直(zhi)到(dao)僅留一(yi)層(ceng)(ceng)靠(kao)近(jin)心(xin)(xin)外膜(mo)的(de)肌橋。該(gai)法(fa)由(you)Guiraudon等于1987年首(shou)創。因(yin)術后左室(shi)受損(sun),現(xian)已少用(yong)。
C.心室隔離術:
僅適用于(yu)右心(xin)(xin)室(shi)(shi)游離壁(bi)或右心(xin)(xin)室(shi)(shi)流出(chu)道(dao)的病(bing)灶。其方法是以右房溝為基(ji)底,圍繞某一(yi)分(fen)(fen)支血管對可疑心(xin)(xin)室(shi)(shi)壁(bi)做半(ban)島狀切(qie)開,使它和(he)右心(xin)(xin)室(shi)(shi)壁(bi)的其余(yu)部(bu)分(fen)(fen)分(fen)(fen)離。
D.外科冷(leng)凍(dong)消融術:
對于(yu)靠(kao)近心臟傳導系統或腱索的(de)病灶(zao),直(zhi)接進行外科手術(shu)(shu)切除術(shu)(shu)可發生嚴重的(de)并發癥,則宜在外科手術(shu)(shu)直(zhi)視下進行冷凍(dong)治(zhi)療,使病灶(zao)降溫至0℃持(chi)續1min。如果有(you)效則降溫至-60℃持(chi)續2min。
E.外科(ke)激光消融術:
用激(ji)光(guang)代(dai)替(ti)冷凍(dong)而消除心律失(shi)常(chang)的病灶。
②冠狀動脈旁路(lu)術(shu):
對于嚴(yan)重冠(guan)(guan)狀(zhuang)動脈病(bing)變(bian)的患者(zhe)進行冠(guan)(guan)狀(zhuang)動脈旁路術(shu)可有(you)效(xiao)的改善心(xin)肌(ji)供血,減輕(qing)或消除心(xin)絞(jiao)痛的癥狀(zhuang)。已有(you)一些多中心(xin)研究結果顯示,冠(guan)(guan)狀(zhuang)動脈旁路術(shu)可延長冠(guan)(guan)心(xin)病(bing)患者(zhe)的生存期(qi),但對心(xin)臟(zang)性猝死發生率的影(ying)響,所見報道(dao)極少。
(1)判斷意識
拍雙(shuang)肩,喚雙(shuang)耳,搭脈(mo)搏,10秒鐘內完成
(2)呼救(jiu)(撥打120)
完成第(di)一步后(hou),馬上拔打(da)120,給病人爭取救治的第(di)一時間。
(3)擺放仰(yang)臥體位
(4)胸外按壓(ya)30次(ci)(ci)(兒童15次(ci)(ci))
位置:胸部正中,兩乳頭連線中點;
姿(zi)勢(shi):肩關節、肘關節、腕關節垂直(zhi)成一條直(zhi)線。
雙手掌(zhang)(zhang)重疊,手指抬(tai)起;掌(zhang)(zhang)根用力。
力度(du):按下(xia)去至(zhi)少5cm;
頻率:至少100次/分鐘(zhong);
(5)開(kai)放(fang)氣(qi)道(仰(yang)頭(tou)舉頦法)
(6)人工吹氣(qi)2次(ci)(兒童(tong)1次(ci))捏鼻(bi),口(kou)包口(kou),吹氣(qi)
(7)重復第(di)四、五(wu)、六步
(8)注意事項:研(yan)究發現,倒地1分(fen)鐘(zhong)(zhong)內(nei)進行心(xin)肺復蘇,救活的概(gai)率為(wei)90%;2分(fen)鐘(zhong)(zhong)內(nei)60%;4分(fen)鐘(zhong)(zhong)內(nei)40%;8分(fen)鐘(zhong)(zhong)內(nei)為(wei)20%;超(chao)過10分(fen)鐘(zhong)(zhong),基本上就是零了。為(wei)了預(yu)防心(xin)源(yuan)性猝死(si),中、老年人(ren)和肥(fei)胖者、糖尿(niao)病者、應定期到醫院(yuan)檢查,發現潛在性心(xin)血管病就及(ji)時(shi)治療,并(bing)應防止各(ge)種誘(you)發因(yin)素。
飲食適宜
建議適當限制辛辣生(sheng)冷刺激性食物。缺血(xue)性心臟病(bing)常(chang)伴(ban)有高血(xue)壓高血(xue)脂(zhi)糖尿(niao)病(bing),如果你(ni)同(tong)時伴(ban)有以上(shang)疾(ji)病(bing),可針對(dui)給予(yu)低鹽低脂(zhi)低糖飲(yin)食。
建議(yi)平時飲(yin)食清(qing)淡,不可集中食用過多蔬菜或高脂食物,低鹽低脂飲(yin)食,少吃動物的(de)內臟,多喝(he)水,避免(mian)辛辣和生冷,戒煙酒,適當運動鍛煉(lian),保(bao)持樂觀舒暢的(de)心情,保(bao)持良好的(de)睡眠,不要長時間熬夜,放(fang)松精神,心態平和。
飲食禁忌
紅(hong)肉:這些肉類含有大量阻塞動脈的飽(bao)和脂肪,不利于(yu)心臟健康(kang)。
汽水:汽水含有大(da)量單糖和(he)熱量,是引起兒童和(he)成人肥(fei)胖的食品之一。
薯(shu)條(tiao):薯(shu)條(tiao)含(han)有飽和(he)脂(zhi)肪(fang)和(he)轉脂(zhi)肪(fang),會引起人們肥(fei)胖,增加心(xin)臟(zang)病風險。
(1)定(ding)期(qi)體(ti)檢(jian):老(lao)年(nian)人本身是心臟(zang)病(bing)及(ji)各種(zhong)疾病(bing)的高發人群,應定(ding)期(qi)到(dao)醫(yi)院進行體(ti)檢(jian)。青、中年(nian)人工作緊張、生活(huo)(huo)節奏(zou)快、工作生活(huo)(huo)壓力大(da)也容易患冠心病(bing)、高血(xue)壓等疾病(bing)。定(ding)期(qi)體(ti)檢(jian)及(ji)早(zao)檢(jian)查(cha)便于及(ji)時(shi)發現疾病(bing),及(ji)早(zao)進行治(zhi)療,減少猝死風險。
(2)避免過度(du)疲勞和精神(shen)緊張:過度(du)疲勞和精神(shen)緊張會(hui)使機體(ti)處于(yu)應激狀態(tai),使血壓升(sheng)高,心臟(zang)負擔加(jia)重,使原有(you)(you)心臟(zang)病加(jia)重。即(ji)使原來沒有(you)(you)器質性(xing)心臟(zang)病也(ye)會(hui)引發室顫的(de)發生。所以,每(mei)個人應該(gai)對自己(ji)的(de)工作、生活有(you)(you)所安排,控制工作節奏(zou)和工作時(shi)間,不(bu)可(ke)過快過長。
(3)戒煙(yan)、限酒、平衡膳食、控(kong)制體重、適當運動,保持良(liang)好的生活習慣會減(jian)少心(xin)腦血管疾病的發生。
(4)注(zhu)意過度(du)(du)疲勞的(de)(de)危險信號及(ji)重視發病的(de)(de)前兆癥狀:長期(qi)過度(du)(du)疲勞會引(yin)發身體(ti)出現一些改變。如焦慮易(yi)怒、記憶力(li)減退、注(zhu)意力(li)不集中、失眠(mian)及(ji)睡眠(mian)質量差、頭(tou)痛頭(tou)暈(yun)耳鳴、性功能(neng)(neng)減退、脫發明顯等。當機(ji)體(ti)出現這些情況(kuang),應(ying)(ying)調(diao)整工作節奏、適(shi)當休息,調(diao)整節奏,保持愉快(kuai)的(de)(de)心情。讓(rang)機(ji)體(ti)功能(neng)(neng)得(de)以(yi)恢(hui)復。如不能(neng)(neng)緩解,應(ying)(ying)立即前往醫院(yuan)救治(zhi)。
(5)對已患有冠心病、高血壓等疾(ji)病的患者應在(zai)醫生指(zhi)導下堅持(chi)服藥治療(liao)。
(6)注意對室性心(xin)律失(shi)常進行危險評估,包括進行常規心(xin)電(dian)圖(tu)、動態(tai)心(xin)電(dian)圖(tu)、其他心(xin)電(dian)學(xue)技術、超聲心(xin)動圖(tu)、心(xin)內電(dian)生理檢查等(deng)檢查,以明確心(xin)律失(shi)常類型,評估心(xin)臟(zang)猝死風險,做(zuo)出治療決策(ce)。
(7)注意加強心梗后心臟(zang)猝死的預防。