Related Experiment Videos
Evaluation of the exercise test in patients with angiographically documented coronary artery disease
Insights
This study shows that the severity of coronary artery disease, indicated by the number of blocked vessels, correlates with exercise test results. More blocked arteries lead to greater ST depression and reduced exercise capacity in male patients.
Area of Science:
- Cardiology
- Exercise Physiology
Background:
- Coronary artery disease (CAD) is a leading cause of mortality worldwide.
- Exercise testing is a common diagnostic tool for CAD.
Purpose of the Study:
- To investigate the relationship between the extent of coronary artery obstruction and submaximal exercise test parameters in male patients.
- To assess how the number of diseased coronary vessels influences ST segment depression, left-ventricular end-diastolic pressure, contractility, and exercise capacity.
Main Methods:
- 100 male patients with significant coronary artery obstruction underwent submaximal exercise testing.
- Exercise test results, including ST depression, were correlated with the number of affected coronary arteries (one-vessel vs. three-vessel disease).
- Left-ventricular function and exercise capacity were also evaluated.
Main Results:
- Patients with three-vessel disease showed significantly greater ST depression ( >2 mm in 44%) compared to those with one-vessel disease (1 mm in 92%).
- Higher ST depression correlated with elevated left-ventricular end-diastolic pressure and impaired contractility.
- Exercise capacity (work performed at 75-100 W/min) was markedly reduced in patients with three-vessel disease (25%) compared to one-vessel disease (92%).
- Peak exercise heart rate and systolic blood pressure decreased as the number of obstructed vessels increased.
Conclusions:
- The number of obstructed coronary arteries is a significant determinant of exercise test responses.
- Exercise testing can effectively differentiate the severity of CAD, with more extensive disease leading to poorer functional capacity and more pronounced ischemic changes.
- These findings underscore the prognostic value of exercise testing in patients with coronary artery disease.
Abstract:
100 male patients with at least 75% obstruction of one or more coronary arteries were subjected to submaximal exercise tests. Among the 73 subjects who had positive tests, 92% of those with one-vessel obstruction had an ST depression of 1 mm, none having more than 2 mm; by contrast, 44% of those with three-vessel disease had an ST depression of more than 2 mm and only 27% on ST depression of 1 mm. Left-ventricular end-diastolic pressure exceeded 15 mm Hg in 86% of the patients who had an ST depression of more than 2 mm but only in 33% of those with a depression of 1 mm; impaired contractility was found in 81% of the former and in 36% of the latter. 92% of those with one-vessel obstruction were able to perform work of 75 and 100 W/min while only 25% of those with three-vessel disease were able to perform the same amount of work. The peak exercise heart rate and systolic blood pressure also decreased with the increase in the number of affected vessels.