Abstract 598: Coronary Flow Reserve Assessed by Quantitative Myocardial Contrast Echocardiography Predicts Mortality in Patients With Heart Failure
Background: Coronary flow reserve (CFR) has been shown to be a predictor of mortality in patients with heart failure (HF). Quantitative MCE is a relatively new method for the assessment of the CFR at the bedside. However, its prognostic value is unknown.
Methods: Ninety-two patients (age: mean±SD: 71±10 years, 60% male) with heart failure (LVEF: 36±14%) underwent low power intermittent MCE (SonoVue) at rest and 2 minutes after dipyridamole infusion. Resting and hyperaemic myocardial blood flow (MBF) [peak contrast intensity × myocardial blood velocity] were obtained and coronary flow reserve (MBF at stress/MBF at rest) was calculated in the anterior and infero-posterior circulation and averaged for each patient. All patients underwent coronary arteriography. Patients were followed-up for mortality.
Results: Of the 92 patients, 44 (48%) patients had coronary artery disease (CAD). There were 19 (21%) deaths during a mean follow up of 54±21 months. Amongst, clincial, LV function parameters and CFR, Cox regression analysis showed that age (p = 0.02), diabetes mellitus (p = 0.06), presence of CAD (p = 0.006) and CFR (p = 0.002) were univariate predictors of mortality. Multivariate analysis showed that CFR (p = 0.03) was the only independent predictor of mortality. A CFR ≤1.5 predicted mortality of 38 % versus 5 % (p = 0.0001) when CFR > 1.5. Kaplan Meier survival analysis is as shown.
Conclusion: CFR determined by MCE is an independent predictor of mortality in patients with HF.