AFib Development Linked to Resting Heart Rate, Short-Term Heart Rate Variability

Cardiac autonomic nervous system (ANS) dysregulation—specifically higher resting heart rate (RHR) and lower heart rate variability (HRV)—is associated with incident atrial fibrillation (AF), results of a new analysis of the Multi-Ethnic Study of Atherosclerosis (MESA) show. This association is independent of known cardiovascular disease (CVD) risk factors, according to the researchers.

The researchers aimed to evaluate the association between baseline RHR and short-term HRV as surrogates of ANS with incident AF among individuals without previous CVD. To conduct their analysis, the researchers studied data on 6261 participants of MESA who had not been diagnosed with AF or CVD.

The researchers used 3 standard 10-second, 12-lead electrocardiograms to measure RHR, the standard deviation of normal-to-normal intervals (SDNN), and the root mean square of successive differences in RR intervals (RMSSD). The researchers adjusted their findings for demographics, atrioventricular nodal agents, and known CVD risk factors.

A total of 754 (12%) participants had developed AF over a mean follow-up of 11.3 ± 3.7 years.

The analysis showed that there was a nonlinear association between RHR, HRV, and incident AF. And in fully adjusted models, higher baseline RHR (>76 beats per minute) was associated with incident AF; this association was not present with lower baseline RHR.

Findings also showed that lower values of RMSDD and SDNN, as well as higher values of RMSDD, were independently associated with incident AF. 

—Colleen Murphy

Reference:

Habibi M, Chahal H, Greenland P, et al. Resting heart rate, short-term heart rate variability and incident atrial fibrillation (from the Multi-Ethnic Study of Atherosclerosis (MESA)). Am J Cardiol. 2019;124(11):1684-1689. https://doi.org/10.1016/j.amjcard.2019.08.025.