Effect of propranolol on perceived exertion soon after myocardial revascularization surgery

Abstract

This study evaluated the effects of propranolol on ratings of perceived exertion (RPE), heart rate (HR), and systolic blood pressure (SBP) during graded exercise testing of myocardial revascularization surgery patients before hospital discharge. Eighty-six men performed a symptom-limited, graded exercise test on a treadmill an average of 11 d after surgery. Patients were assigned to three groups: those not taking propranolol (no-propranolol group, N = 54), those taking propranolol (propranolol group, N = 22), and those exhibiting exertional hypotension during testing (hypotensive group, N = 10). Test results showed that estimated METs during peak exercise were similar for the three groups. The propranolol group demonstrated a lower HR for submaximal and peak exercise when compared with the no-propranolol group, but RPE was the same for matched exercise intensities. The hypotensive group failed to increase SBP during exercise, but perceived the matched exercise intensities to he the same as the other two groups. The HR response of the hypotensive group was similar to that of the no-propranolol group. Thus, an abnormal SBP response during exercise was not reflected in a changed RPE when compared with patients who increased SBP appropriately. It was concluded that propranolol does not affect RPE during graded exercise testing soon after cardiac surgery.