Neurohumoral prediction of benefit from carvedilol in ischemic left ventricular dysfunction
Richards AM., Doughty R., Nicholls MG., Macmahon S., Ikram H., Sharpe N., Espiner EA., Frampton C., Yandle TG.
Background - Plasma neurohormones were analyzed for prediction of adverse outcomes and response to treatment in 415 patients with ischemic left ventricular dysfunction randomly assigned to receive carvedilol or placebo. Methods and Results - Atrial natriuretic peptide, brain natriuretic peptide (BNP), or norepinephrine (NE) levels above the group median were associated with increased mortality rates and heart failure. On multivariate analysis, both BNP and NE interacted with treatment to predict death or heart failure independent of age, New York Heart Association class, and left ventricular ejection fraction. For placebo, supramedian levels of BNP were associated with 3-fold the mortality rate of inframedian levels (20/104; 19% vs 6/99; 6%; P < 0.01). For carvedilol, mortality rate was comparable in these 2 subgroups (12/109; 11% vs 8/94; 9%; NS). Corresponding rates for heart failure were 29/104 (28%) versus 3/99 (3%; P < 0.001) for placebo and 16/109 (15%) versus 7/94 (7%; NS) for carvedilol. High NE levels did not predict additional benefit from carvedilol, which significantly reduced heart failure admissions only in those with NE levels below the median (13.1% to 4.0%; P < 0.01). In the 23% of the study population with supramedian BNP but inframedian levels of NE, carvedilol reduced hospital admission with heart failure by >90% (P < 0.001). Conclusions - Carvedilol reduced mortality rates and heart failure in those with higher pretreatment BNP levels but lesser activation of plasma NE. Neurohumoral profiling may guide introduction of β- blockade in heart failure.