Implications of Heart Rate in Patients with Left Ventricular Assist Devices.

Optimal heart rate (HR) is a promising therapeutic target in patients with heart failure with reduced ejection fraction. Nevertheless, the implication of optimal HR in patients with left ventricular assist devices (LVAD) remains unknown. The cohort included consecutive patients with sinus rhythm undergoing LVAD implantation between 2014 and 2018. Ideal HR was calculated as follows: 93 - 0.13 × (deceleration time [msec]). The impact of "HR difference," defined as an HR difference between the actual HR at discharge and the calculated ideal HR, on the 1-year mortality and heart failure readmissions was investigated. A total of 143 patients (55 years old, 101 men) was identified and tertiled considering their HR differences: (1) the optimal HR group (n = 49; HR difference < 27 bpm), (2) the suboptimal HR group (n = 47; HR difference = 27-42 bpm), and (3) the nonoptimal HR group; HR difference (n = 47; HR difference > 43 bpm). The nonoptimal HR group had a significantly higher 1-year cumulative incidence of the primary endpoint compared with the optimal HR group (38% versus 16%, P = 0.029) with a hazard ratio of 1.69 (95% confidence interval 1.02-2.57) adjusted for 6 potential confounders. In conclusion, nonoptimized HR negatively affected clinical outcomes in LVAD patients. The implication of deceleration time-guided HR optimization in LVAD patients should be further investigated.