[Serial evaluation by effort test of the effects of coronary artery bypass on effort angina (author's transl)].

To evaluate the duration of favourable effects of coronary artery bypass (CAB) on exercise-induced angina (A), 58 patients: 13 with single 21 with double and 24 with triple vessel disease, were studied. All patients underwent CAB for stable angina on effort. Patients underwent exercise testing (ET) before surgery at one, two and three years. Heart rate peak (HR), HR x systolic blood pressure peak (DP), work load (W), exercise-induced ST segment depression (ST) and incidence of A were evaluated; the results of ET before surgery were compared with those found after CAB. Our findings show that HR, DP, W and ST were significantly improved by surgery for at least 3 years. The lowest incidence of A was found at one year ET (20.6%), while it increased at two years (27,5%) and three years ET (37.9%). Most patients with A had angiographic evidence of left ventricular abnormal wall motion and ec-graphic signs of previous myocardial infarction. Our data indicate that serial exercise testing can objectively monitor the results of CAB. Most patients show an improved exercise tolerance for up to 3 years after CAB. Some patients, with more extensive CAD, showed a progressive deterioration of the clinical pattern and a decrease of the exercise tolerance.