Lewis William R, Ganim Rick, Sabapathy Rajendran
Division of Cardiovascular Medicine, Department of Internal Medicine, University of California Davis School of Medicine, Sacramento, California 95817, USA.
Crit Pathw Cardiol. 2007 Sep;6(3):127-30. doi: 10.1097/HPC.0b013e31812da7dc.
The aim of the study was to determine the utility of stress echocardiography for identification of significant coronary artery disease (CAD) in higher-risk patients with an underlying left bundle-branch block (LBBB).
Patients with LBBB undergoing stress echocardiography were divided into 2 groups: group 1 (no history MI), group 2 (history MI). Positive stress echocardiograms were compared with the presence of >50% luminal-diameter stenosis during coronary angiography. During the follow-up (FU) period, cardiac events were determined for hard and soft endpoints.
Sixty consecutive patients with LBBB underwent stress echocardiography. Twenty-eight patients had a positive stress echocardiogram (20 group 1; 8 group 2). Nineteen of these patients underwent coronary angiography (14 group 1; 5 group 2). In group 1, regional wall motion abnormality (RWMA) correlated with coronary anatomy in only 5 patients, while in group 2, RWMA correlated with coronary anatomy in only 2 patients. There were 12 false positives, with echocardiographic abnormalities identified. The positive predictive values in groups 1 and 2 were 35.7% and 40%, respectively. During the FU period, there was 1 mortality, 2 MI, 2 coronary revascularizations, and 6 hospitalizations (2 chest pain, 1 CHF, 3 coronary angiography). The negative predictive value for hard endpoints was 83%.
Stress echocardiography has a poor positive predictive value to identify significant angiographic CAD in higher-risk patients with LBBB; however, the negative predictive value for hard ischemic events is similar to patients without LBBB.
本研究的目的是确定负荷超声心动图在患有潜在左束支传导阻滞（LBBB）的高危患者中识别严重冠状动脉疾病（CAD）的效用。
接受负荷超声心动图检查的LBBB患者被分为两组：第1组（无心肌梗死病史），第2组（有心肌梗死病史）。将负荷超声心动图阳性结果与冠状动脉造影时管腔直径狭窄>50%的情况进行比较。在随访期（FU）内，确定心脏事件的硬终点和软终点。
连续60例LBBB患者接受了负荷超声心动图检查。28例患者负荷超声心动图阳性（第1组20例；第2组8例）。其中19例患者接受了冠状动脉造影（第1组14例；第2组5例）。在第1组中，仅5例患者的节段性室壁运动异常（RWMA）与冠状动脉解剖结构相关，而在第2组中，仅2例患者的RWMA与冠状动脉解剖结构相关。有12例假阳性，表现为超声心动图异常。第1组和第2组的阳性预测值分别为35.7%和40%。在随访期内，有1例死亡、2例心肌梗死、2例冠状动脉血运重建和6次住院（2例胸痛、1例心力衰竭、3例冠状动脉造影）。硬终点的阴性预测值为83%。
负荷超声心动图在患有LBBB的高危患者中识别显著的造影剂CAD的阳性预测值较低；然而，硬缺血事件的阴性预测值与无LBBB的患者相似。
