Randomized comparison between the invasive and conservative strategies in comorbid elderly patients with non-ST elevation myocardial infarction.

Background: Comorbid elderly patients with non-ST-elevation myocardial infarction (non-STEMI) are underrepresented in randomized trials and undergo fewer cardiac catheterizations according to registries. Our aim was to compare the conservative and invasive strategies in these patients.

Methods: Randomized multicenter study, including 106 patients (January 2012-March 2014) with non-STEMI, over 70years and with comorbidities defined by at least two of the following: peripheral artery disease, cerebral vascular disease, dementia, chronic pulmonary disease, chronic renal failure or anemia. Patients were randomized to invasive (routine coronary angiogram, n=52) or conservative (coronary angiogram only if recurrent ischemia or heart failure, n=54) strategy. Medical treatment was identical. The main endpoint was the composite of all-cause mortality, reinfarction and readmission for cardiac cause (postdischarge revascularization or heart failure), at long-term (2.5-year follow-up). Analysis of cumulative event rate (incidence rate ratio=IRR) and time to first event (hazard ratio=HR), were performed.

Results: Cardiac catheterization/revascularization rates were 100%/58% in the invasive versus 20%/9% in the conservative arm. There were no differences between groups in the main endpoint (invasive vs conservative: IRR=0.946, 95% CI 0.466-1.918, p=0.877) at long-term. The invasive strategy, however, tended to improve 3-month outcomes in terms of mortality (HR=0.348, 95% CI 0.122-0.991, p=0.048), and of mortality or ischemic events (reinfarction or postdischarge revascularization) (HR=0.432, 95% CI 0.190-0.984, p=0.046). This benefit declined during follow-up.

Conclusions: Invasive management did not modify long-term outcome in comorbid elderly patients with non-STEMI. The finding of a tendency towards an improvement in the short-term needs confirmation in larger studies (clinicaltrials.govNCT1645943).