The effect of coronary revascularization on exercise-induced ventricular ectopic activity.

The effect of coronary artery bypass graft surgery (CABGS) on the prevalence of exercise-induced ventricular ectopic activity was studied in 43 patients (42 male, 1 female). Their age was 53 +/- 7.8 (mean +/- SD) years. Treadmill exercise test (TET) was performed within a month prior to and three months post-CABPGS. An average of 2.8 grafts per patient were used. Nine of the 43 patients (20.9%) had premature ventricular contractions (PVCs) related to effort prior to CABGS, while 12 out of the 43 (27.9%) had PVCs post-surgery. Seven patients (16.3%) had PVCs for the first time after successful revascularization, four of whom had previous myocardial infarction. The haemodynamic parameters of the total group during TET showed significant improvement in the duration of the exercise test (37%), the double product heart rate X systolic blood pressure (36%)M and the cardiorespiratory fitness (31%). Our data indicate that the ventricular ectopic activity induced by exercise in patients with coronary artery disease is not affected by successful revascularization. On the contrary, a significant number of patients develop new ventricular ectopy after CABGS where a pre-existing myocardial infarction appears to be a determining factor.