肥厚型心肌病和冠状动脉血管舒张储备受损患者心内膜下小动脉结构改变：心肌缺血的一个可能原因。

Alterations of the architecture of subendocardial arterioles in patients with hypertrophic cardiomyopathy and impaired coronary vasodilator reserve: a possible cause for myocardial ischemia.

作者信息

Schwartzkopff B, Mundhenke M, Strauer B E

机构信息

Department of Cardiology, Pneumology and Angiology, Heinrich Heine University, Düsseldorf, Germany.

出版信息

J Am Coll Cardiol. 1998 Apr;31(5):1089-96. doi: 10.1016/s0735-1097(98)00036-9.

DOI:10.1016/s0735-1097(98)00036-9

PMID:9562012

Abstract

OBJECTIVES

The study was designed to investigate the architecture of subendocardial arterioles of patients with hypertrophic cardiomyopathy (HCM) and angina pectoris with respect to coronary vasodilator reserve.

BACKGROUND

There is growing evidence that the coronary microvasculature is abnormal in HCM. Arterioles, which mainly regulate intramyocardial blood flow, are especially suspect.

METHODS

Thirteen patients with HCM (50.1+/-12.6 years old, mean value +/- SD) were studied after exclusion of any relevant coronary stenoses. Subendocardial arterioles (density [n/mm2], wall area [microm2], percent lumen area [%lumen], periarteriolar collagen area [microm2]), myocyte diameter (microm) and interstitial collagen fraction (Vv%) were evaluated by means of stereologic morphometry of transvenous biopsy samples. Coronary blood flow was measured quantitatively with the inert chromatographic argon method at basal conditions and after dipyridamole (0.5 mg/kg body weight over 4 min intravenously), and coronary vasodilator reserve was calculated as the ratio of coronary resistance at basal conditions and after pharmacologic vasodilation. Data from five normotensive subjects (45.4+/-11 years old, p = NS) served as control data.

RESULTS

Arteriolar density was diminished by 38% (p = 0.004) and %lumen by 13% (p = 0.009) in patients with HCM compared with control subjects. Coronary reserve was impaired in patients with HCM (2.28+/-0.6 vs. 5.34+/-1.49, p = 0.003) because of higher coronary resistance after vasodilation (0.48+/-0.14 vs. 0.22+/-0.06 mm Hg x min x 100 g/ml, p = 0.004). Coronary vasodilator reserve correlated with arteriolar density (r = +0.47, p = 0.045) and with %lumen (r = 0.65, p = 0.003).

CONCLUSIONS

In HCM, the architecture of preterminal subendocardial arterioles is altered by a reduced total cross-sectional lumen area, corresponding to an impaired coronary vasodilator capacity that may predispose to myocardial ischemia.

摘要

目的

本研究旨在调查肥厚型心肌病（HCM）合并心绞痛患者的心内膜下小动脉结构及其冠脉血管舒张储备情况。

背景

越来越多的证据表明，HCM患者的冠脉微血管存在异常。主要调节心肌内血流的小动脉尤其值得怀疑。

方法

排除任何相关冠脉狭窄后，对13例HCM患者（年龄50.1±12.6岁，均值±标准差）进行研究。通过经静脉活检样本的体视学形态计量法评估心内膜下小动脉（密度[n/mm²]、管壁面积[μm²]、管腔面积百分比[%管腔]、动脉周围胶原面积[μm²]）、心肌细胞直径（μm）和间质胶原分数（Vv%）。在基础状态下以及静脉注射双嘧达莫（0.5mg/kg体重，4分钟内）后，采用惰性色谱氩气法对冠脉血流进行定量测量，并计算冠脉血管舒张储备，即基础状态下与药物性血管舒张后冠脉阻力之比。来自5名血压正常受试者（年龄45.4±11岁，p=无显著差异）的数据作为对照数据。

结果

与对照受试者相比，HCM患者的小动脉密度降低了38%（p=0.004），管腔面积百分比降低了13%（p=0.009）。HCM患者的冠脉储备受损（2.28±0.6对5.34±1.49，p=0.003），原因是血管舒张后冠脉阻力更高（0.48±0.14对0.22±0.06mmHg×min×100g/ml，p=0.004）。冠脉血管舒张储备与小动脉密度（r=+0.47，p=0.045）以及管腔面积百分比（r=0.65，p=0.003）相关。