Effect of long-term exercise training on regional myocardial perfusion changes in patients with coronary artery

The cardiac rehabilitation of patients with coronary artery disease (CAD) p romotes exercise tolerance, improves left ventricular function, and decreas es the heart rate and systolic blood pressure at the same load intensity. S everal studies have shown that cardiac rehabilitation improves myocardial p erfusion in CAD patients. However, the long-term (greater than or equal to 1 year) effect of cardiac rehabilitation on myocardial perfusion is still c ontroversial. The effect of long-term exercise training on myocardial perfu sion in CAD patients was assessed using thallium-201 (Tl-201) exercise stud ies at a baseline (4 months after the onset of CAD) and at a 1-year or more follow-up in 58 patients with stable CAD. The subjects had been divided in to a training group (n=35) participating in supervised exercise 2 times per week for the follow-up period, and the control group (n=23). There was an improvement in the myocardial perfusion on stress Tl-201 scintigraphy in 20 of the 35 (57.1%) trained patients and in 3 of the 23 (13.0%) of the contr ol patients (p<0.001). The number of Tl-201 stress myocardial perfusion def ect segments was significantly decreased after the cardiac rehabilitation t raining (231 to 153 segments), but showed no change in the control group (1 58 to 156 segments) (p<0.01). In spite of no significant differences in the number of involved coronary arteries, it improved (12/17 patients: 70.6%) more in the patients who had trained for more than 2 years compared to the patients who had trained for less than 2 years. The exercise tolerance incr eased in 25 of the 35 training group patients (71.4%), and in only 3 of the 23 control group patients (13.0%). The peak double products increased from 20,131+/-6,010 to 28,370+/-5,600 (p<0.01) in the training group, and showe d no change in the control group (20,567+/-5,112 to 20,964+/-7,728 (NS)). T he results indicated that the long-term physical training increased exercis e tolerance and the double products of CAD patients. In addition, the train ing resulted in improved cardiac perfusion as evidenced by Tl-201 scintigra phy. The findings suggest that exercise training is an advisable and effect ive treatment for patients with CAD.