Continuing evolution of therapy for coronary artery disease. Initial results from the era of coronary angioplasty.

Abstract

BACKGROUND Survival after coronary artery bypass graft surgery (CABG) and medical therapy in patients with coronary artery disease (CAD) has been studied in both randomized trials and observational treatment comparisons. Over the past decade, the use of coronary angioplasty (PTCA) has increased dramatically, without guidance from either randomized trials or prospective observational comparisons. The purpose of this study was to describe the survival experience of a large prospective cohort of CAD patients treated with medicine, PTCA, or CABG. METHODS AND RESULTS The study was designed as a prospective nonrandomized treatment comparison in the setting of an academic medical center (tertiary care). Subjects were 9263 patients with symptomatic CAD referred for cardiac catheterization (1984 through 1990). Patients with prior PTCA or CABG, valvular or congenital disease, nonischemic cardiomyopathy, or significant (> or = 75%) left main disease were excluded. Baseline clinical, laboratory, and catheterization data were collected prospectively in the Duke Cardiovascular Disease Databank. All patients were contacted at 6 months, 1 year, and annually thereafter (follow-up 97% complete). Cardiovascular death was the primary end point. Of this cohort, 2788 patients were treated with PTCA (2626 within 60 days) and 3422 with CABG (3080 within 60 days). Repeat or crossover revascularization procedures were counted as part of the initial treatment strategy. Kaplan-Meier survival curves (both unadjusted and adjusted for all known imbalances in baseline prognostic factors) were used to examine absolute survival differences, and treatment pair hazard ratios from the Cox model were used to summarize average relative survival benefits. For the latter, a 13-level CAD prognostic index was used to examine the relation between survival and revascularization as a function of CAD severity. The effects of revascularization on survival depended on the extent of CAD. For the least severe forms of CAD (ie, one-vessel disease), there were no survival advantages out to 5 years for revascularization over medical therapy. For intermediate levels of CAD (ie, two-vessel disease), revascularization was associated with higher survival rates than medical therapy. For less severe forms of two-vessel disease, PTCA had a small advantage over CABG, whereas for the most severe form of two-vessel disease (with a critical lesion of the proximal left anterior descending artery), CABG was superior. For the most severe forms of CAD (ie, three-vessel disease), CABG provided a consistent survival advantage over medicine. PTCA appeared prognostically equivalent to medicine in these patients, but the number of PTCA patients in this subgroup was low. CONCLUSIONS In this first large-scale, prospective observational treatment comparison of PTCA, CABG, and medicine, we confirmed the previously reported survival advantages for CABG over medical therapy for three-vessel disease and severe two-vessel disease. For less severe CAD, the primary treatment choices are between medicine and PTCA. In these patients, there is a trend for a relative survival advantage with PTCA, although absolute survival differences were modest. In this setting, treatment decisions should be based not only on survival differences but also on symptom relief, quality of life outcomes, and patient preferences.

Prediction of 1-Year Survival After Thrombolysis for Acute Myocardial Infarction in the Global Utilization of Streptokinase and TPA for Occluded Coronary Arteries Trial

“…Percutaneous or surgical revascularization after the acute event is associated with an early hazard, followed by a reduced risk of death over the later period. Studies of elective bypass surgery, 21,22 angioplasty, 23 and revascularization after MI 24 all show this pattern. Thus, the lower mortality rates of survivors of the acute phase should not be taken as definitive evidence that revascularization prolongs survival (also keeping in mind the possibility of selection of a less-sick subgroup), just as the increased mortality rates in the first few days after revascularization should not be taken to indicate that revascularization increases mortality rates overall.…”

Technological development and medical productivity: the diffusion of angioplasty in New York state

“…those with medium-severity CAD) become more likely to receive PTCA relative to CABG over time. Modifying an index from Mark et al (1994), we divide patients into three severity categories: low, medium, and high. 8 This categorization provides a rough control for the effects of any changes over time in the average severity of the population receiving revascularization.…”

Outcomes of revascularization strategies for two-vessel coronary artery disease involving the proximal left anterior descending artery in an era of improved pharmacotherapy and stenting

“…This patient population is one of the most controversial, from an outcome perspective. Early registry studies comparing PTCA and CABG showed a trend toward improved survival following surgical revascularization in this patient population (17)(18)(19)(20)(21). However, RCTs from the PCI era, which used stents and GP IIb/IIIa inhibitors, are conflicting.…”

“…Several registry studies comparing balloon angioplasty (percutaneous transluminal coronary angioplasty [PTCA]) and CABG showed a trend toward improved survival following surgical revascularization in this patient population (18)(19)(20)(21). However, RCTs from the PCI era, which used stents and glycoprotein (GP) IIb/IIIa inhibitors, are conflicting.…”