How to consider target heart rate in patients with systolic heart failure

Abstract

Aims Heart rate reduction therapy using ivabradine, a selective inhibitor of the funny current of the sinoatrial node, is widely used in the systolic heart failure cohort. However, the optimal target of heart rate remains controversial. The association between heart rate and 'overlap' between E-wave and A-wave in the pulse wave transmitral flow Doppler echocardiography might be a key to find the ideal heart rate in each individual. Methods and results We performed transthoracic echocardiography in patients with systolic heart failure, and the association between heart rate, deceleration time, and overlap length between E-wave and A-wave was assessed. In total, 368 patients with systolic heart failure (median 76 years old, 190 men, median ejection fraction 40%) were included. The measured overlap length was 35 (À72, 115) ms. Given the results of multiple linear regression analyses, we constructed a formula: estimated overlap length (ms) = À589 + 6.2 × heart rate (bpm) + 0.81 × deceleration time (ms), which had a good agreement with actually measured one (r = 0.62). The ideal heart rate, at which the overlap length is 'zero' and probably cardiac output is maximized, is calculated as follows: ideal heart rate (bpm) = 93-0.13 × deceleration time (ms). Conclusions We proposed a novel formula using deceleration time to estimate ideal heart rate that achieves a zero overlap between E-wave and A-wave in patients with systolic heart failure. Prognostic impact of the formula-guided heart rate optimization should be studied.

The implication of optimal heart rate in patients with systolic dysfunction following TAVR

“…Our team previously hypothesized that cardiac output might be maximized when the overlap length between the E‐wave and A‐wave at transmitral Doppler echocardiographic flow is “zero.” Given that the overlap length had a linear association with heart rate and deceleration time, we proposed a formula to calculate the ideal heart rate for each individual by substituting zero in the overlap length: ideal heart rate (bpm) = 93 − 0.13 × (deceleration time [ms]) 7 . Our team is currently conducting a prospective study investigating the association between the optimization of heart rate using ivabradine and improvement in cardiac output, which is estimated by using AESCULON mini (Osypka Medical) 11 …”

“…The deceleration time of E‐wave in the transmitral Doppler echocardiography was also measured. The ideal heart rate was calculated according to the following formula: 93 − 0.13 × (deceleration time [ms]) 7 . A difference between the actual heart rate and ideal heart rate was calculated for each patient.…”

“…Our team recently proposed a formula to calculate the ideal heart rate for each individual with systolic dysfunction using the deceleration time of E‐wave obtained by transmitral Doppler echocardiography, 7 at which E‐wave and A‐wave stand adjacent each other and the cardiac output is theoretically maximized. We hypothesized that optimal heart rate might be associated with better clinical outcomes accompanied by better cardiac reverse remodeling in patients with systolic dysfunction following TAVR.…”

Implication of Ivabradine in Up-titrating Beta-blocker in a Patient with Advanced Heart Failure

“…Our team recently proposed a formula to calculate the ideal heart rate using the deceleration time: 96−0.13× (deceleration time), at which the overlap length between the two waves is theoretically zero ( 6 ). For example, given that the deceleration time was 121 msec in this case, the ideal heart rate was calculated as 78 bpm.…”

“…The trends in trans-mitral Power Doppler echocardiography are shown in Fig. 2 ( 6 ). Just before starting ivabradine administration ( Fig.…”