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Background: The traditional central European approach to cardiac rehabilitation involves sending patients to an idyllic setting, where they reside for a specified period following a cardiac event. Favorable results have [...]

There are two approaches to treating disease of the coronary arteries, the vessels that deliver blood to the heart itself, in current clinical use: coronary artery bypass grafting (CABG), in which a healthy vessel from the patient's own body is grafted into the heart's circulatory system, allowing the blood to bypass the diseased vessel; and percutaneous transluminal coronary angioplasty (PTCA), in which a small balloon is threaded into the diseased vessel and inflated to widen the vessel until blood can flow freely again. An early clinical recommendation was that patients with disease in more than one artery should receive CABG, with PTCA being the treatment of choice for single-vessel disease. However, PTCA is now becoming more common even when several arteries are constricted. Exercise test results of 27 published studies of patients who had undergone either procedure are reviewed, to determine whether clearer clinical guidelines for recommending one over the other could be developed. Methodological problems of evaluating such a broad sample of research reports are discussed. The degrees of reduction of ischemia (diminished blood supply to the heart) and improvement in blood flow were the same after both procedures, although more than twice as many patients with disease in several vessels had received CABG. Both approaches reduced angina (chest pain) by about 50 percent and ST-segment depression (a segment of the electrocardiogram associated with damage to the coronary arteries) by 35 to 40 percent. Overall restenosis rates (redevelopment of constriction) for PTCA are known to be 30 to 35 percent of treated vessels within six months after the procedure; after CABG, 10 to 15 percent of the grafts become occluded (blocked) again during the same period. The two procedures are comparable in many ways, but PTCA patients, in general, have less severe coronary artery stenosis. (Consumer Summary produced by Reliance Medical Information, Inc.)

The purposes of this study were 1) to determine the prognosis of silent ischemia in an unselected group of patients referred for exercise testing, and 2) to assess whether age or the presence of myocardial infarction or diabetes mellitus influences the prevalence of silent myocardial ischemia during exercise testing.

To evaluate the variability in the reported accuracy of the exercise electrocardiogram (ECG) for predicting severe coronary disease, meta analysis was applied to 60 consecutively published reports comparing exercise-induced ST depression with coronary angiographic findings. The 60 reports included 62 distinct study groups comprising 12,030 patients who underwent both tests. Both technical and methodologic factors were analyzed.

The failure of exercise-induced ST segment depression to consistently predict prognosis in patients after myocardial infarction could be a result of population differences and the rest electrocardiogram (ECG). These hypotheses were tested by studying 198 veterans who survived a myocardial infarction, underwent a submaximal predischarge treadmill exercise test and were followed up for cardiac events for 2 years. During the 2 years, 29 deaths, 19 reinfarctions and 28 revascularization procedures were documented. The prevalence of death or reinfarction was two times higher in patients who had exercise-induced ST depression than in patients who did not. However, in the 55 patients without Q waves, the risk increased to 11 times for an abnormal ST response.