Sympathetic Nerve Activity Efferent Drive and Beta-Blocker Treatment　– Effect of Interaction in Systolic Heart Failure –

Abstract

Background:Although both β-blocker dose (BBD) and sympathetic activity efferent drive are associated with prognosis in chronic heart failure (HF), little is known about the prognostic value of the interaction between them.

Methods and Results:Potential prognostic variables including resting muscle sympathetic nerve activity (MSNA) were investigated in 133 patients with HF (ejection fraction [EF] <0.45). BBD was normalized to therapeutically equivalent doses of carvedilol. Primary cardiovascular endpoints included cardiovascular death and HF hospitalization. Predictors for outcomes were assessed on univariate, multivariate, and Kaplan-Meier analysis. EF was followed for 9 months after MSNA measurement in 102 patients. During the 1,419±824-day follow-up period, 24 patients died (sudden death, n=10; progressive HF, n=14). On multivariate Cox proportional hazard analysis, higher MSNA (P=0.037; HR, 2.01) and lower BBD (<5.0 mg/day; P=0.041; HR, 1.94) were independent predictors of cardiovascular events. Patients were divided into higher MSNA (≥64 bursts/100 beats) and lower MSNA groups. Although lower BBD remained an independent predictor in patients with higher MSNA, BBD was not statistically significant in patients with lower MSNA on univariate analysis. Additionally, there was a lower EF change in patients with lower BBD and higher MSNA.

Conclusions:Higher BBD might be necessary to avoid cardiovascular events in HF patients with central sympathetic overactivation. (Circ J 2016; 80: 2149–2154)