短暂性心肌缺血期间的血压变化：对机制的见解

Blood pressure changes during transient myocardial ischemia: insights into mechanisms.

作者信息

Rehman A, Zalos G, Andrews N P, Mulcahy D, Quyyumi A A

机构信息

Cardiology Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892-1650, USA.

出版信息

J Am Coll Cardiol. 1997 Nov 1;30(5):1249-55. doi: 10.1016/s0735-1097(97)00289-1.

DOI:10.1016/s0735-1097(97)00289-1

PMID:9350923

Abstract

OBJECTIVES

We investigated the contribution of changes in systemic blood pressure to the genesis of spontaneous myocardial ischemia.

BACKGROUND

Although increases in heart rate often precede the development of spontaneous myocardial ischemia, it remains a subject of controversy whether these are accompanied by simultaneous changes in blood pressure.

METHODS

Using an ambulatory monitoring device that triggered blood pressure recordings from the level of the ST segment, we documented systolic and diastolic blood pressure and heart rate changes related to episodes of ST segment depression in 17 patients with stable coronary artery disease.

RESULTS

Systolic blood pressure and heart rate, but not diastolic pressure, increased significantly before the onset of ST segment depression and persisted throughout the ischemic episode. There was a significant correlation between the changes in heart rate and systolic blood pressure during episodes of myocardial ischemia (r = 0.5, p = 0.0005) and between heart rate and systolic blood pressure changes at 1-mm ST segment depression during treadmill exercise testing and ambulatory monitoring (r = 0.73, p = 0.0005 for heart rate; r = 0.77, p = 0.0008 for systolic blood pressure), indicating that patients with a low heart rate threshold during ischemic episodes also had a lower systolic blood pressure threshold before ischemia during both tests. Circadian changes in systolic blood pressure paralleled the variations in heart rate and ischemic episodes, with the lowest values at night.

CONCLUSIONS

Significant increases in myocardial oxygen demand, including systolic blood pressure, occur during episodes of spontaneous myocardial ischemia. Patients with a lower heart rate threshold during ischemic episodes had a lower systolic blood pressure threshold during both ambulatory monitoring and treadmill exercise. The effects of antianginal therapy on blood pressure changes during ischemia need to be explored further.

摘要

目的

我们研究了系统性血压变化对自发性心肌缺血发生的作用。

背景

虽然心率增加常常先于自发性心肌缺血的发生，但这些变化是否伴有同时发生的血压变化仍存在争议。

方法

我们使用一种动态监测设备，该设备能在ST段水平触发血压记录，记录了17例稳定型冠心病患者与ST段压低发作相关的收缩压、舒张压和心率变化。

结果

收缩压和心率在ST段压低发作前显著升高，并在整个缺血发作期间持续升高，而舒张压无明显变化。心肌缺血发作期间心率变化与收缩压变化之间存在显著相关性（r = 0.5，p = 0.0005），在平板运动试验和动态监测中，ST段压低1毫米时心率与收缩压变化之间也存在显著相关性（心率r = 0.73，p = 0.0005；收缩压r = 0.77，p = 0.0008），这表明在这两种测试中，缺血发作期间心率阈值低的患者在缺血前收缩压阈值也较低。收缩压的昼夜变化与心率变化和缺血发作平行，夜间值最低。