Acute Vascular Response to Exercise in Women With Nonobstructive Coronary Artery Disease

The purpose of this study is to examine the acute effect of exercise on vascular function in women with nonobstructive coronary artery disease.

Women are more likely to have nonobstructive coronary artery disease (CAD) . The purpose of this study is to examine the acute effect of exercise on vascular function in women with nonobstructive coronary artery disease. Endothelium-dependent and -independent dilation, arterial stiffness and wave reflection will be measured at baseline and after walking on a treadmill at a slow pace for 47 minutes. Endothelium-dependent dilation will be measured using brachial artery flow-mediated dilation via high resolution ultrasonography. Endothelium-independent dilation will be measured using brachial artery dilation to sublingual nitroglycerin. Arterial stiffness and wave reflection will measured using applanation tonometry.

Brachial artery endothelium-dependent flow-mediated dilation to reactive hyperemia will be measured using high resolution ultrasonography. To determine flow-mediated dilation, brachial artery diameter and blood velocity will be measured before and after occluding the forearm for 5 minutes by inflating a cuff to 250 mmHg.

To determine vascular smooth muscle responsiveness to nitric oxide, brachial artery diameter will be measured using high resolution ultrasonography before and after sublingual administration of 0.4mg nitroglycerin.

Inclusion Criteria: women with non-obstructive coronary artery disease documented within the past 5 years by coronary angiogram as no coronary arteries with stenosis greater than 50% lesions age 18 to 89 years able to complete maximal graded exercise test Exclusion Criteria: use of tobacco products within the previous six months use of oral contraceptives or hormone replacement therapy within the prior year pregnancy (positive urine pregnancy test) or lactation history of hepatic disease or infection with hepatitis B, C or HIV