Prognostic value of exercise echocardiography in patients with left ventricular systolic dysfunction and known or suspected coronary artery disease

Abstract

The prognostic value of exercise echocardiography (ExE) in patients with left ventricular systolic dysfunction (LVSD) has not been characterized. We sought to assess the value of ExE for predicting outcome in patients with LVSD and known/suspected coronary artery disease. This study is a retrospective analysis of a prospectively collected database of 1,107 patients who underwent treadmill ExE and had resting LVSD (left ventricular ejection fraction <50%). Ischemia was defined as an increase in wall motion score index from rest to exercise. The end points were all-cause mortality and major cardiac events (MACE). Overall, 494 patients (44.6%) developed new or worsening wall motion abnormalities. During a mean follow-up of 4.1 +/- 3.4 years, 301 patients died and 166 had a MACE. In patients with mild LVSD, the 5-year mortality rate was 8.8% in those without ischemia and 21% in those with ischemia (P < .001). For patients with moderate LVSD without ischemia, the 5-year mortality rate was 18.3%, whereas it was 29.2% when ischemia was present (P = .009). In those with severe LVSD, the 5-year mortality rate was 23.9% without ischemia and 35.7% with ischemia (P = .03). In the multivariate analysis, increase in wall motion score index was an independent predictor of mortality (hazard ratio 2.25, 95% CI 1.26-2.06, P = .001) and MACE (hazard ratio 2.60, 98% CI 1.34-5.04, P = .005). The addition of the ExE results to clinical, resting echocardiography and exercise variables provided significant incremental prognostic information for predicting mortality (P = .001) and MACE (P = .005). The ExE provides significant information for predicting outcome in patients with LVSD and known/suspected coronary artery disease.