肥厚型心肌病患者运动及多巴酚丁胺负荷试验时的左心室收缩功能障碍

Left ventricular systolic dysfunction during exercise and dobutamine stress in patients with hypertrophic cardiomyopathy.

作者信息

Okeie K, Shimizu M, Yoshio H, Ino H, Yamaguchi M, Matsuyama T, Yasuda T, Taki J, Mabuchi H

机构信息

Second Department of Internal Medicine, School of Medicine, Kanazawa University, Japan.

出版信息

J Am Coll Cardiol. 2000 Sep;36(3):856-63. doi: 10.1016/s0735-1097(00)00818-4.

DOI:10.1016/s0735-1097(00)00818-4

PMID:10987611

Abstract

OBJECTIVES

We sought to characterize stress-induced left ventricular systolic dysfunction in patients with hypertrophic cardiomyopathy (HCM).

BACKGROUND

Myocardial ischemia and diastolic dysfunction occur in patients with HCM. We hypothesized that, in the setting of transient myocardial ischemia, left ventricular systolic dysfunction occurs during exercise and dobutamine stress.

METHODS

We studied 39 patients with HCM but without obstructive symptoms at rest or coronary artery disease. A continuous ventricular function monitor equipped with cadmium telluride detectors (VEST) was used to evaluate left ventricular function during supine bicycle ergometer exercise. Dobutamine stress echocardiography (DSE) was also performed. The left ventricular ejection fraction (LVEF) and regional wall motion were determined from echocardiographic images.

RESULTS

Changes in the LVEF correlated between exercise and dobutamine stress (r = 0.643, p < 0.0001). The LVEF decreased more than 5% at peak exercise in 17 of patients (group II), while the other patients had normal responses (group I). New regional wall motion abnormalities during dobutamine infusion were detected in 18 of 110 (16.4%) segments in group I and 42 of 85 (49.4%) segments in group II. Decreased or unchanged regional wall motion occurred more frequently in hypertrophied segments than in nonhypertrophied segments (p < 0.0001). There were significant inverse correlations between the LVEF responses during both stresses and the number of abnormal segments noted during dobutamine stress in all patients (VEST: p < 0.005; DSE: p < 0.0005). Signs of left ventricular obstruction were observed in 11 of 39 patients during DSE. However, there was no significant correlation between the LVEF response and the dobutamine-induced left ventricular pressure gradient.

CONCLUSIONS

Exercise-induced systolic dysfunction occurred in 50% of patients with HCM. In these patients, regional wall motion abnormalities were present in hypertrophied segments.

摘要

目的

我们试图对肥厚型心肌病（HCM）患者应激诱导的左心室收缩功能障碍进行特征描述。

背景

HCM患者会出现心肌缺血和舒张功能障碍。我们假设，在短暂性心肌缺血的情况下，运动和多巴酚丁胺应激期间会发生左心室收缩功能障碍。

方法

我们研究了39例静息时无梗阻症状且无冠状动脉疾病的HCM患者。使用配备碲化镉探测器的连续心室功能监测仪（VEST）评估仰卧位自行车测力计运动期间的左心室功能。还进行了多巴酚丁胺负荷超声心动图（DSE）检查。根据超声心动图图像确定左心室射血分数（LVEF）和节段性室壁运动。

结果

运动和多巴酚丁胺应激期间LVEF的变化具有相关性（r = 0.643，p < 0.0001）。17例患者（II组）在运动峰值时LVEF下降超过5%，而其他患者反应正常（I组）。I组110个节段中有18个（16.4%）在多巴酚丁胺输注期间检测到新的节段性室壁运动异常，II组85个节段中有42个（49.4%）出现异常。肥厚节段中节段性室壁运动减弱或无变化的情况比非肥厚节段更常见（p < 0.0001）。在所有患者中，两种应激期间的LVEF反应与多巴酚丁胺应激期间观察到的异常节段数量之间存在显著负相关（VEST：p < 0.005；DSE：p < 0.0005）。DSE期间39例患者中有11例观察到左心室梗阻迹象。然而，LVEF反应与多巴酚丁胺诱导的左心室压力梯度之间无显著相关性。