Improving risk assessment with cardiac testing in peripheral arterial disease

PURPOSE: The study's objective was to evaluate the prognostic value of left ventricular ejection fraction and stress-induced ischemia during dobutamine stress echocardiography, in addition to ankle-brachial index measurements and clinical risk factors in patients with suspected or known peripheral arterial disease.

METHODS: In 852 patients with suspected or known peripheral arterial disease (mean age 63 years, 70% male), the ankle-brachial index was measured, left ventricular ejection fraction was assessed, and all patients underwent additional stress testing. Endpoints were all-cause mortality and hard cardiac events (cardiac death or nonfatal myocardial infarction).

RESULTS: During a mean follow-up of 7.6+/-4.4 years, death occurred in 288 patients (34%), and hard cardiac events occurred in 216 patients (25%). Mean left ventricular ejection fraction was 50%+/-17%, and stress-induced ischemia was observed in 352 patients (41%). In multivariate analysis with adjustment for clinical risk factors and ankle-brachial index, each 5% decrease in left ventricular ejection fraction was associated with increased all-cause mortality (hazard ratio [HR] 1.05, 95% confidence interval [CI], 1.02-1.09) and hard events (HR 1.14, 95% CI, 1.08-1.21). Stress-induced ischemia also independently predicted all-cause mortality (HR 2.01, 95% CI, 1.38-2.79) and hard events (HR 2.06, 95% CI, 1.39-3.08). Left ventricular ejection fraction and stress-induced ischemia provided incremental prognostic information over clinical data and ankle-brachial index values (P <.001).

CONCLUSIONS: Left ventricular ejection fraction and stress-induced ischemia independently predict long-term outcome and improve prognostic risk assessment, in addition to ankle-brachial index and clinical risk factors in patients with suspected or known peripheral arterial disease.