Bourassa, Martial G.

Background Cardiac mortality and myocardial infarction (MI) rates are used to evaluate the efficacy of coronary artery bypass grafting (CABG) and percutaneous transluminal coronary angioplasty (PTCA). We compared 5-year cardiac mortality and MI rates in 1829 patients with multivessel disease randomized to CABG or PTCA. Methods and Results The 5-year cardiac mortality rate was 8.0% in patients assigned to PTCA compared with 4.9% in those assigned to CABG (relative risk [RR] of 1.55 with a 95% confidence interval [CI] of 1.07 to 2.23; P =.022). In a subgroup of 1476 nondiabetic patients, there were no significant differences between treatment groups in cardiac mortality either overall (4.6% versus 4.2%; RR=1.04, 95% CI, 0.65 to 1.66; P =.908) or in subgroups based on symptoms, left ventricular function, number of diseased vessels, or stenotic proximal left anterior descending artery. The two treatment groups had similar event rates for the combined end point of cardiac death or MI. The RR for cardiac mortality in 264 patients who sustained an MI compared with those who did not was 5.9 ( P <.001). MIs were more common after CABG during index hospitalization ( P =.004), but in the PTCA group, they were more common after discharge ( P <.001). Conclusions The Bypass Angioplasty Revascularization Investigation (BARI) trial indicates 5-year cardiac mortality in patients with multivessel disease was significantly greater after initial treatment with PTCA than with CABG. The difference was manifest in diabetic patients on drug therapy. There were no significant differences overall for the composite end point of cardiac mortality or MI between treatment groups or for cardiac mortality in nondiabetic patients regardless of symptoms, left ventricular function, number of diseased vessels, or stenotic proximal left anterior descending artery.

Background The NHLBI Percutaneous Transluminal Coronary Angioplasty (PTCA) Registry followed 1345 consecutive patients with first PTCA between 1977 and 1981 (registry 1) and 2136 consecutive patients with PTCA between 1985 and 1986 (registry 2). Changes in patient selection and in immediate and 1-year outcome are presented. This report extends to 5 years the comparison of the effects of early and more recent management with PTCA. Methods and Results Sixteen participating centers entered consecutive patients who had angioplasty for the first time between 1977 and 1981 and between 1985 and 1986. Patients with recent myocardial infarction (MI) were excluded. Vessel disease was defined according to the Coronary Artery Surgery Study. Successful dilatation required ≥20% reduction in luminal narrowing and <50% lumen diameter stenosis after intervention. Routine annual follow-up was conducted by telephone interview. The product-limit method was used to estimate freedom from untoward events, Cox regression analysis to model relative risk and adjusted relative risk of events between the two registries, and logistic regression when the exact time of outcome (such as recurrence of symptoms) was not known. Long-term event rates were computed by vessel disease for all patients and for the cohort of patients with initially successful PTCA. After adjustment for extent of disease, diabetes, prior bypass surgery (CABG), hypertension, age, and sex, the 5-year risk of death was similar in the two registry cohorts. However, rates of MI, CABG, and a combined outcome measure of death, MI, and/or CABG were significantly lower in the registry 2 cohort both for all patients and for patients who were initially treated successfully. Use of repeated PTCA was higher, and freedom from symptoms without adverse events was significantly better in the latter cohort. Conclusions Compared with registry 1, the management of the registry 2 cohort resulted in lower 5-year morbid event rates and reduced CABG operations. Mortality rates remained similar. When symptomatic status was considered in combination with events, a significantly better outcome was seen overall and in the initially successful cohort. In registry 2, repeated PTCA was used with much greater frequency early after the initial procedure.

Background —Patients with treated diabetes in the randomized-trial segment of the Bypass Angioplasty Revascularization Investigation (BARI) who were randomized to initial revascularization with PTCA had significantly worse 5-year survival than patients assigned to CABG. This treatment difference was not seen among diabetic patients eligible for BARI who opted to select their mode of revascularization. We hypothesized that differences in patient characteristics, assessed and unmeasured, together with the treatment selection in the registry, at least partially account for this discrepancy. Methods and Results —Among diabetics taking insulin or oral hypoglycemic drugs at entry, angiographic and clinical presentations were comparable between randomized and registry patients. However, more registry patients were white, and registry diabetics tended to be more educated and more physically active and to report better quality of life. Procedural characteristics and in-hospital complications were comparable. The 5-year all-cause mortality rate was 34.5% in randomized diabetic patients assigned to PTCA versus 19.4% in CABG patients ( P =0.0024; relative risk [RR]=1.87); corresponding cardiac mortality rates were 23.4% and 8.2%, respectively ( P =0.0002; RR=3.10). The CABG benefit was more apparent among patients requiring insulin. In the registry, all-cause mortality was 14.4% for PTCA versus 14.9% for CABG ( P =0.86, RR=1.10), with corresponding cardiac mortality rates of 7.5% and 6.0%, respectively ( P =0.73; RR=1.07). These RRs in the registry increased to 1.29 and 1.41, respectively, after adjustment for all known differences between treatment groups. Conclusions —BARI registry results are not inconsistent with the finding in the randomized trial that initial CABG is associated with better long-term survival than PTCA in treated diabetic patients with multivessel coronary disease suitable for either surgical or catheter-based revascularization.

Background — Data are absent that compare midterm angiographic outcome between patients with and without diabetes after initial percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass graft surgery (CABG). Importantly, diabetes mellitus may differentially influence long-term survival after PTCA or CABG. Methods and Results — Patients with multivessel coronary disease who were previously enrolled in the Bypass Angiopathy Revascularization Investigation to compare initial PTCA versus CABG (n=1829) and who had a reduction in jeopardized myocardium after initial revascularization and at least 1 angiogram during 5-year follow-up were analyzed (n=897). This included 369 CABG-treated patients (16% with diabetes) and 528 PTCA-treated patients (18% with diabetes). The influence of diabetes on angiographic increase in percentage of jeopardized myocardium after initial revascularization with either PTCA or CABG was investigated. Among PTCA patients, the mean percentage increase in total jeopardized myocardium was significantly greater in those with diabetes than in those without at 1-year protocol-directed angiography (42% versus 24%, P =0.05) and on the first clinically performed (unscheduled) angiogram within 30 months (63% versus 50%, P =0.01) but not at 5-year protocol-directed angiography (34% versus 26%, P =0.33). This excess midterm risk associated with diabetes persisted after statistical adjustment. In contrast, among CABG patients, diabetes was not associated with percentage increase in jeopardized myocardium at any angiographic follow-up interval. Conclusions — Presence of diabetes differentially influences worsening of jeopardized myocardium after initial PTCA compared with CABG. This differential effect occurs irrespective of whether follow-up angiography is undertaken for clinical or nonclinical purposes.