Nigam A, Humen D P
Division of Cardiology, University of Alberta Hospital, Edmonton, Canada.
J Nucl Med. 1998 Apr;39(4):579-81.
The detection of myocardial ischemia in patients with preexisting left bundle branch block (LBBB) remains problematic. Pharmacologic hyperemia with dipyridamole is now used routinely in such patients for detection of significant coronary artery disease. Little data exists on the prognostic value of cardiac nuclear scintigraphy in patients with preexisting LBBB. The purpose of our study was to determine the prognostic value of cardiac nuclear scintigraphy in patients with preexisting LBBB.
Ninety-six patients with preexisting LBBB underwent perfusion imaging between July 1987 and June 1995. Thirty-seven underwent planar 201Tl imaging, and 59 underwent SPECT sestamibi imaging. Images were interpreted by consensus of two experienced observers and classified as normal, abnormal low risk and abnormal high risk. Outcomes measured were survival, cardiac and noncardiac death. The final study group included 43 women and 53 men, aged 42-83 (mean 66 +/- 9). Average follow-up was 3.4 +/- 2.1 yr.
Of the 96 patients examined, 31 had normal scans, 39 had low-risk scans and 26 had high-risk scans. At the end of the study period, 27 patients with normal scans were still alive while 2 suffered cardiac death and 2 suffered noncardiac death. Of those with low-risk scans, 36 survived while 2 suffered cardiac death and 1 suffered noncardiac death. Finally, of those with high-risk scans, 17 survived while 8 suffered cardiac death and 1 suffered noncardiac death (chi-square test, p = 0.020).
Dipyridamole imaging is an important prognostic tool for predicting future cardiac events in patients with preexisting LBBB and aids in their risk stratification for coronary artery disease.
对于已有左束支传导阻滞（LBBB）的患者，心肌缺血的检测仍然存在问题。双嘧达莫药物负荷试验目前常用于此类患者以检测严重冠状动脉疾病。关于已有LBBB的患者心脏核素显像的预后价值，现有数据较少。我们研究的目的是确定已有LBBB的患者心脏核素显像的预后价值。
1987年7月至1995年6月期间，96例已有LBBB的患者接受了灌注显像。37例接受了平面201Tl显像，59例接受了SPECT司他比显像。图像由两名经验丰富的观察者共同解读，并分为正常、低风险异常和高风险异常。测量的结果包括生存率、心脏性死亡和非心脏性死亡。最终研究组包括43名女性和53名男性，年龄42 - 83岁（平均66±9岁）。平均随访时间为3.4±2.1年。
在96例接受检查的患者中，31例扫描结果正常，39例为低风险扫描，26例为高风险扫描。在研究期结束时，31例扫描结果正常的患者仍存活，2例死于心脏性死亡，2例死于非心脏性死亡。低风险扫描的患者中，36例存活，2例死于心脏性死亡，1例死于非心脏性死亡。最后，高风险扫描的患者中，17例存活，8例死于心脏性死亡，1例死于非心脏性死亡（卡方检验，p = 0.020）。
双嘧达莫显像对于预测已有LBBB患者未来的心脏事件是一种重要的预后工具，并有助于对其进行冠状动脉疾病的风险分层。
