Impact of metabolic syndrome on the outcome of patients with stable coronary artery disease submitted to different types of treatment: 10-year follow-up of the MASS II study

Abstract

Purpose: Metabolic syndrome (MetS) is understood as a condition that promotes atherosclerosis and confers an additional risk of adverse cardiovascular eventsin patients with coronary artery disease. The prognosis of this syndrome in this subset of patients in a long term follow up is inconclusive. Evaluate the impact of metabolic syndrome on cardiac death in patients with symptomatic chronic multivessel coronary artery disease. Methods: Patients randomized in MASS II study submitted to coronary artery bypass graft (CABG),angioplasty (PCI) or medical treatment (MT) were evaluated for the presence of MetS and followed prospectively for 10 years. We evaluated the incidence of overall and cardiac death in this period. Results: Criteria for MetS were fulfilled in 283 patients of 583 (54%) randomized to three therapeutic strategies. The presence of MetS was associated with an increased cardiac related death in studied population. During a 10-year follow- up, the probability cardiac mortality free survival was significantly different among patients in the 2 groups (MetS = 81,6% x non-MetS = 91,3% P=0.004). Stratifying patients with MetS by therapeutic approach we identify a statistical difference in cardiac death free survival comparing interventional approaches (CABG and PCI) to MT: 82,4% for CABG; 86,2% for PCI and 75,9% for MT(P=0,003). Besides, there is a group with best prognosis: patients without MetS submitted to CABG presenting 98,7% of patients free of cardiac death in a 10-year follow-up. Conclusion: MetS confers high rates of cardiac death in patients with stable coronary artery disease irrespective of therapeutic strategy used. In patients with MetS, interventional approaches (PCI or CABG) seem to confer more protection against cardiac death in a 10-year follow-up.