Problem of Angioplasty in Diabetics

Coronary artery bypass graft surgery improves survival for certain subsets of patients with coronary artery disease and has been accepted as the revascularization “gold standard” since the 1970s. PTCA, introduced by Gruentzig in 1977, was initially envisioned as a potentially serial treatment for patients with focal coronary artery disease to prevent the development of complex disease severe enough to require CABG. By the mid-1980s, however, expertise and technology had improved to the point that PTCA could, apparently with reasonable success and safety, be brought to bear on anatomic situations previously considered to be solely the realm of the cardiovascular surgeon. To ascertain whether PTCA for patients with moderately advanced disease was truly an appropriate alternative to CABG, several RCTs were undertaken. At the time, it appeared that both revascularization alternatives were sufficiently mature that the long-term results would be relevant when they became available 5 to 10 years later. In aggregate, 4310 patients with multivessel disease thought to be suitable for either form of revascularization (thereby excluding many patients with far advanced disease) were enrolled in six RCTs between 1986 and 1991. The overall trial results were remarkably concordant. CABG was associated with a slight but not statistically significant survival advantage, less angina, and far fewer later revascularizations. PTCA led to a slight but insignificant reduction in myocardial infarction over the ensuing 2 to 5 years.1 2 3 4 5 6 Critics of RCTs often contest the generalizability of the treatment outcomes reported. They question whether it might be an oversimplification to apply the overall results of a trial both to all of its component patients and also to all similar but nonrandomized patients. In fact, given the general homogeneity engendered by the focus of most clinical trials, it is unusual for some patients to benefit and others to …