Active strategy of detecting and treating asymptomatic MSAD results in no clinical benefit

In patients with high-risk coronary artery disease (CAD), an active strategy of detecting and treating asymptomatic multisite artery disease (MSAD) combined with intensive medical therapy did not improve 2-year outcomes compared to a more traditional approach of managing only  symptomatic coronary and extracoronary lesions, new research shows.

Findings from the AMERICA (Active detection and Management of the Extension of atherothrombosis in high Risk coronary patients In comparison with standard of Care for coronary Atherosclerosis) study were presented during a Hot Line session at ESC Congress 2016.

The study, conducted by the ACTION study group (www.action-coeur.org), found no significant difference between the intensive and standard approaches in 2-year rates of all-cause mortality, rehospitalisation for an ischemic event, or organ failure, reported lead investigator Jean-Philippe Collet, MD, PhD from the Institut de Cardiologie Hopital Pitié-Salpetrière, in Paris France.

The prevalence and the associated-risk of asymptomatic extra-coronary lesions (ECL) in high risk coronary patients are unknown, and whether their systematic identification and appropriate treatment is relevant, has never been established, said Professor Collet.

The study enrolled 521 CAD patients who were considered high-risk based on either recently diagnosed three-vessel disease (within the past 6 months) or acute coronary syndrome in the past month (in patients ≥75 years old).

The patients were randomised to a pro-active prevention program including revascularization of asymptomatic MSAD when appropriate, life style changes, and an aggressive pharmacological approach (n=263); or to a more conventional strategy based on treatment of CAD and only symptomatic ECL (n=258).

There was no difference in the rate of the primary endpoint (44.9%) compared to patients in the conventional strategy group (43.0%; hazard ratio, 1.03; 95% confidence interval [CI], 0.80 to 1.34], reported Professor Collet.

Similarly, there were no significant differences in the rate of the main secondary end point: a composite of all-cause death, myocardial infarction, stroke and any revascularization. This occurred in 12.9% of the patients in the intensive group and 13.6% of those in the conventional group (hazard ratio, 0.94; 95% CI, 0.58 to 1.50).

Major bleeding events also occurred at a similar rate (4.6% vs 5.0% respectively; hazard ratio, 0.97; 95% CI, 0.40 to 1.91).

Although the intensive strategy identified asymptomatic MSAD in 23% of patients, and resulted in aggressive secondary prevention in 45.3%, it led to very few additional revascularization procedures (3.6%),  and ultimately resulted in no clinical benefit over conventional management, concluded Professor Collet.

"Possible explanations for the failure of the pro-active strategy were that revascularization of MSAD lesions was rare and that pharmacological treatment was close to optimal in both groups," he said, adding, "This study has important practical implications for the daily life."