Maladaptation after successful revascularization in anginal patients without transmural infarction

In order to elucidate how peripheral or cardiac function maladaptations play a role in deconditioning after coronary bypass surgery, we have evaluated effects of successful coronary artery bypass grafting (CABG) and percutaneous transluminal angioplasty (PTCA) on exercise capacity in anginal patients without myocardial infarction. Symptom-limited treadmill exercise tests were performed in 46 patients before and after CABG and in 28 patients before and after PTCA. None of the patients carried out a cardiac rehabilitation program after their discharge. PTCA patients showed significant improvement of exercise capacity, from 6.4 +/- 1.6 to 10.5 +/- 2.5 METs in 4 weeks after PTCA, and even elderly PTCA patients showed improvement from 6.0 +/- 1.1 to 10.3 +/- 2.5 METs. However, the exercise capacity of CABG patients improved only from 5.9 +/- 1.4 to 8.5 +/- 3.1 METs in the first 6 months after CABG, and from 5.9 +/- 1.7 to 10.0 +/- 3.6 METs thereafter. The 15 elderly CABG patients showed only slight increase of physical activity, from 6.0 +/- 1.7 to 6.9 +/- 1.9 METs in the first 6 months after CABG and from 6.3 +/- 1.9 to 8.7 +/- 2.9 METs thereafter. Furthermore, 6 of 15 elderly CABG patients showed no improved exercise capacity after CABG. There was no correlation between the duration of anginal symptoms before CABG and exercise capacity before or after CABG. These findings suggest that CABG itself and/or physical restriction during admission produces peripheral function maladaptation and may be the main contributors to deconditioning after CABG, especially in elderly patients. This deconditioning can be treated by a rehabilitation program after the discharge.