Clinical features and outcomes of women with unstable ischemic heart disease: observations from metabolic efficiency with ranolazine for less ischemia in non-ST-elevation acute coronary syndromes-thrombolysis in myocardial infarction 36 (MERLIN-TIMI 36).

BACKGROUND: The pathobiological basis of ischemic heart disease and thus the manifestations and response to therapy can differ between women and men. In prior studies, sex-based treatment differences have been observed with the antiischemic ranolazine, with a possibly diminished effect in women.

METHODS AND RESULTS: We conducted a prospectively planned analysis of the clinical, biomarker, angiographic, and continuous ECG features and 1-year outcomes of women with unstable ischemic heart disease randomized to ranolazine or placebo in Metabolic Efficiency With Ranolazine for Less Ischemia in Non-ST-Elevation Acute Coronary Syndromes-Thrombolysis in Myocardial Infarction 36 (MERLIN-TIMI 36). Compared with men (n=4269), women (n=2291) were older with more risk factors (P<0.001). On presentation, women were less likely than men to have significant epicardial coronary artery disease (no stenosis >or=50% on angiography, 19.4% versus 8.6%; P<0.001) or elevated troponin (57.1% versus 68.9%; P<0.001). Yet, women were more likely to have an elevated B-type natriuretic peptide (47.0% versus 40.2%; P<0.001), worse median angina frequency scores (80 versus 100; P<0.001), and an ischemic episode on continuous ECG administered during the first 7 days (22.5% versus 19.3%; P=0.0025). Women and men were at similar adjusted risk for the primary end point of cardiovascular death, myocardial infarction, or recurrent ischemia (adjusted hazard ratio, 1.11; 95% confidence interval, 0.96 to 1.29; P=0.15). Ranolazine was associated with a significant reduction in recurrent ischemia in women (13.0% versus 18.2%; hazard ratio, 0.71; 95% confidence interval, 0.57 to 0.88; P=0.002).

CONCLUSIONS: Women with a clinical syndrome consistent with unstable ischemic heart disease, despite having less obstructive coronary artery disease, were more likely than men to report anginal episodes and had more recorded ischemic periods on continuous ECG. In this setting, ranolazine may be a particularly useful antiischemic agent in women.

CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT00099788.