medwireNews: Coronary artery bypass graft (CABG) offers a significant survival advantage over medical therapy for patients with diabetes and multivessel coronary artery disease (CAD), MASS II trial results indicate.
By contrast, over 10 years of cardiac follow up, percutaneous coronary intervention (PCI) offered no significant advantage over medical therapy for patients with at least 70% stenosis in two or more major vessels or their major branches and a preserved left ventricular ejection fraction, report the MASS (Medicine, Angioplasty, or Surgery Study) II authors in the American Heart Journal.
Similar to results after 1 and 5 years of follow up, 10-year mortality and 10-year cardiac mortality rates were significantly higher in the 232 patients with diabetes than the 379 patients without diabetes, at 32.3% versus 23.2% and 19.4% versus 12.7%, respectively.
When patients with diabetes were assessed separately, the team found that the 10-year rate of mortality was significantly higher for the 88 patients treated with medical therapy than the 80 patients treated with CABG (37.5 vs 27.5%). A nonsignificant difference was found for the 64 patients treated with PCI, at 31.3%.
The corresponding 10-year cardiac mortality rates were 26.1%, 12.5%, and 18.8%, with the difference between medical therapy and CABG again reaching significance.
Patients with diabetes who received CABG were also significantly less likely to require further intervention than those given medical therapy or PCI, at 5.0% versus 27.2% and 20.3%, respectively.
"The apparent positive effect of CABG among population despite diabetes status could reside in the completeness of revascularization and the use of LIMA [left internal mammary artery] in this subset of patients," suggest Whady Hueb (Heart Institute Hospital, University of São Paulo, Brazil) and co-authors.
"We found significantly fewer stents per patient than grafts per patient in PCI and CABG groups, respectively, and consequently more incomplete revascularization in the PCI compared to the CABG group," they explain.
The MASS II investigators note that the results must be interpreted in the context of the pre-drug eluting stent treatment period, with the therapeutic glucose and lipid targets and lesion measures used at the time.
Nevertheless, they add: "It is important to highlight that the medical treatment regimen dispensed to all groups in relation to medical usage and therapeutic goals in follow-up are comparable to those in some contemporary trials."
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2013