Long-term follow-up of a randomized, controlled clinical trial of three therapeutic strategies for multivessel stable coronary artery disease in women

Abstract

Objectives: Coronary artery disease is the leading cause of death in women. The proposed treatments for women are similar to those for men. However, in women with multivessel stable coronary artery disease and normal left ventricular function, the best treatment is unknown.

Methods: A post hoc analysis of the MASS II study with 10 years of follow-up, mean (standard deviation) 6.8 (3.7) years, enrolled between May 1995 and May 2000, evaluated 188 women with chronic stable multivessel coronary artery disease who underwent medical treatment, percutaneous coronary intervention or coronary artery bypass graft surgery. Primary end-points were incidence of total mortality, Q-wave myocardial infarction, or refractory angina. Data were analysed according to the intention-to-treat principle.

Results: Women treated with percutaneous coronary intervention and medical treatment had more primary events than those treated with coronary artery bypass graft surgery, respectively, of 34, 44 and 22% (P = 0.003). Survival rates at 10 years were 72% for coronary artery bypass graft surgery, 72% for percutaneous coronary intervention and 56% for medical treatment (P = 0.156). For the composite end-point, Cox regression analysis adjusted for age, diabetes, hypertension, treatment allocation, prior myocardial infarction, smoking, number of vessels affected and total cholesterol, had a higher incidence of primary events with medical treatment than with coronary artery bypass graft surgery [hazard ratio (HR) = 2.38 (95% confidence interval (CI): 1.40-4.05); P = 0.001], a lower incidence with percutaneous coronary intervention than with medical treatment [HR = 0.60 (95% CI: 0.38-0.95); P = 0.031] but no differences between coronary artery bypass graft surgery and percutaneous coronary intervention. Regarding death, a protective effect was observed with percutaneous coronary intervention compared with medical treatment [HR = 0.44 (95% CI: 0.21-0.90); P = 0.025].

Conclusions: Percutaneous coronary intervention and coronary artery bypass graft surgery compared with medical treatment had better results after 10 years of follow-up.

Keywords: Coronary artery bypass graft; Coronary disease; Percutaneous coronary intervention; Treatment; Women.