A 55-year-old man who had had an anterior-wall myocardial infarction six months previously is admitted with an exacerbation of congestive heart failure. An electrocardiogram shows sinus rhythm with a left bundle-branch block; an echocardiogram demonstrates a left ventricular ejection fraction of 25 percent. He is treated with furosemide, lisinopril, and carvedilol. However, during an office visit three months later, he reports persistent shortness of breath with mild exertion.

還有什麼招嗎? (常被這句話問到)..

嚴重心衰竭病患(NYHA Function class III~IV),且已經接受目前認為最佳的藥物治療..包括ACE inhibitor, beta-blocker, diuretics, aldosterone antagonist..但是還是常常心衰竭發作因而是急診室的常客..

你要再給他更多更多的藥物嗎?..讓他吃到飽?..還是..

看看ECG吧..可能看到lead V1有rSR' pattern, lead V6有slurred S wave..且QRS interval >0.13 msec..也就是left-bundle branch block (LBBB)..

這時候..可以開始考慮biventricular pacing了..跟一般pacemaker不同的是..biventricuale的目的不在於on demand pacing..而是在同步化(synchronization)..同步誰跟誰呢?因為LBBB的病患,心臟中隔會先收縮..接著才是左心室..這樣的非同步化會使心臟輸出量下降..因此造成了心臟衰竭的病徵..

目前美國心臟醫學會(AHA)對於使用biventricular pacing的建議是:

- 對藥物治療反應不佳
- 有症狀的NYHA function class III或IV心衰竭
- QRS寬度大於130 msec
- 左心室舒張末期寬度至少55 mm
- 且LVEF<30%

Adapted from N Engl J Med. 2006; 355: 288-94.