J C Kaski1, G Rosano, S Gavrielides, L Chen. 1. Department of Cardiological Sciences, St. George's Hospital Medical School, London, England, United Kingdom.
Abstract
OBJECTIVES: This study was conducted to test the hypothesis that angiotensin-converting enzyme inhibition may lessen myocardial ischemia in patients with microvascular angina. BACKGROUND:Patients with syndrome X (angina pectoris, positive findings on exercise testing and normal coronary arteriogram) have a reduced coronary vasodilator reserve ("microvascular angina") and may show an increased sympathetic drive. Angiotensin-converting enzyme inhibition attenuates sympathetic coronary vasoconstriction in patients with coronary artery disease. METHODS:Ten patients (seven women and three men, mean age [+/- SD] 53 +/- 6 years) with syndrome X and a reduced coronary flow reserve underwent a randomized, single-blind, crossover, placebo-controlled study of the effects of the angiotensin-converting enzyme inhibitor enalapril on angina and exercise-induced ST segment depression. Assessment was by symptom-limited treadmill exercise testing after 2 weeks of treatment with 10 mg/day of enalapril and after 2 weeks of placebo administration. RESULTS: All patients had positive findings on exercise testing (> or = 1 mm ST segment depression and angina) while taking placebo, whereas six patients had a positive test result (four with angina) during enalapril therapy. Total exercise duration and time to 1 mm of ST segment depression were prolonged by enalapril over those obtained with placebo (mean 779 +/- 141 vs. 690 +/- 148 s, p = 0.006 and 690 +/- 204 vs. 485 +/- 241 s, p = 0.007, respectively). The magnitude of ST segment depression was also less with enalapril than with placebo (mean 1.1 +/- 0.4 vs. 1.5 +/- 0.2 mm, p = 0.004). Heart rate and blood pressure at peak exercise and at 1 mm of ST depression were not significantly different during placebo and enalapril treatment. CONCLUSIONS:Angiotensin-converting enzyme inhibition lessens exercise-induced ischemia in patients with syndrome X and microvascular angina, probably by a direct modulation of coronary microvascular tone, which results in an increased myocardial oxygen supply.
RCT Entities:
OBJECTIVES: This study was conducted to test the hypothesis that angiotensin-converting enzyme inhibition may lessen myocardial ischemia in patients with microvascular angina. BACKGROUND:Patients with syndrome X (angina pectoris, positive findings on exercise testing and normal coronary arteriogram) have a reduced coronary vasodilator reserve ("microvascular angina") and may show an increased sympathetic drive. Angiotensin-converting enzyme inhibition attenuates sympathetic coronary vasoconstriction in patients with coronary artery disease. METHODS: Ten patients (seven women and three men, mean age [+/- SD] 53 +/- 6 years) with syndrome X and a reduced coronary flow reserve underwent a randomized, single-blind, crossover, placebo-controlled study of the effects of the angiotensin-converting enzyme inhibitor enalapril on angina and exercise-induced ST segment depression. Assessment was by symptom-limited treadmill exercise testing after 2 weeks of treatment with 10 mg/day of enalapril and after 2 weeks of placebo administration. RESULTS: All patients had positive findings on exercise testing (> or = 1 mm ST segment depression and angina) while taking placebo, whereas six patients had a positive test result (four with angina) during enalapril therapy. Total exercise duration and time to 1 mm of ST segment depression were prolonged by enalapril over those obtained with placebo (mean 779 +/- 141 vs. 690 +/- 148 s, p = 0.006 and 690 +/- 204 vs. 485 +/- 241 s, p = 0.007, respectively). The magnitude of ST segment depression was also less with enalapril than with placebo (mean 1.1 +/- 0.4 vs. 1.5 +/- 0.2 mm, p = 0.004). Heart rate and blood pressure at peak exercise and at 1 mm of ST depression were not significantly different during placebo and enalapril treatment. CONCLUSIONS:Angiotensin-converting enzyme inhibition lessens exercise-induced ischemia in patients with syndrome X and microvascular angina, probably by a direct modulation of coronary microvascular tone, which results in an increased myocardial oxygen supply.
Authors: Mark A Marinescu; Adrián I Löffler; Michelle Ouellette; Lavone Smith; Christopher M Kramer; Jamieson M Bourque Journal: JACC Cardiovasc Imaging Date: 2015-02
Authors: Daniel F Pauly; B Delia Johnson; R David Anderson; Eileen M Handberg; Karen M Smith; Rhonda M Cooper-DeHoff; George Sopko; Barry M Sharaf; Sheryl F Kelsey; C Noel Bairey Merz; Carl J Pepine Journal: Am Heart J Date: 2011-09-06 Impact factor: 4.749