Brain natriuretic peptide and the risk of ventricular tachyarrhythmias in mildly symptomatic heart failure patients enrolled in MADIT-CRT

BACKGROUND There are limited data about the correlation between brain natriuretic peptide (BNP) levels and arrhythmic risk assessment in patients who receive device therapy for the treatment of heart failure (HF) or for the prevention of sudden cardiac death. OBJECTIVES We aimed to investigate the association between BNP levels and the risk of ventricular tachyarrhythmias among mildly symptomatic HF patients who receive an intracardiac defibrillator (ICD) with or without cardiac resynchronization therapy (respectively, CRT-D or CRT). METHODS The study population involved 1197 patients enrolled in MADIT-CRT. Plasma BNP was measured in a core laboratory at baseline and after 1-year follow-up. Ventricular tachycardia/fibrillation (VT/VF) events were identified from ICD/CRT-D interrogations. RESULTS Multivariate Cox hazards regression modeling showed that elevated baseline ( > median = 72 ng/L) and 1 -year BNP were associated with a significant increase in the risk of VT/VF (HR = 1.36, P=.026; and HR = 1.79, P<.001, respectively); and VT/VF or death (HR = 1.37, P=.008; and HR = 1.84, P<.0001, respectively) during follow-up. At 1 year post device implantation, BNP levels were significantly lower among study patients treated with CRT-D as compared with those who received ICD only (P=.014). CRT-D patients who had greater than median reductions in BNP levels (greater than one-third reduction of initial value) experienced a significantly lower risk of subsequent VT/VF (HR = 0.61, P=.021) and VT/VF or death (HR = 0.45, P<.0001) as compared to patients without such reductions. CONCLUSIONS In MADIT-CRT, elevated baseline and follow-up BNP levels were independent predictors of increased risk for subsequent ventricular tachyarrhythmias, whereas BNP reductions following CRT-D implantation identified patients with a lower incidence of VT/VF during follow-up.