Zhidan Li,* Yan Fang,* Junlin Wu, Wenxia Ma

Department of Cardiology, The First People’s Hospital of Yibin, Yibin, Sichuan, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Zhidan Li, Department of Cardiology, The First People’s Hospital of Yibin, Yibin, Sichuan, People’s Republic of China, Email leezhd@163.com

Objective: To investigate the correlation between premature ventricular contraction (PVC) frequency and heart rate (HR) in Chinese adults, with an emphasis on sex-specific differences in clinical characteristics.
Patients and Methods: This retrospective study analyzed 24-hour Holter monitoring data from 478 inpatients at the First People’s Hospital of Yibin between January 2021 and December 2022. The inclusion criteria were age ≥ 18 years, ≥ 20 hours of Holter recording, frequent PVCs (≥ 500 PVCs), and complete clinical profiles. Patients were stratified into three groups on the basis of the hourly correlation between PVC counts and HR: fast heart rate-related PVC (F-HR-PVC), slow heart rate-related PVC (S-HR-PVC), and independent heart rate-related PVC (I-HR-PVC). Heart rate variability (HRV) indices were assessed to evaluate autonomic nervous system activity.
Results: Among the 478 patients, 267 were males and 211 were females with a mean age of 65.7± 13.0 years. The mean PVC burden was 5.7± 7.0%, and the mean left ventricular ejection fraction (LVEF) was 59.1± 8.7%. In males, the F-HR-PVC group was most common (45.3%), while in females, the I-HR-PVC group was most prevalent (50.2%). Despite these observed differences, a chi-square test did not reveal statistically significant differences in the distribution of VPC profiles between sexes (P=0.167). Analysis of clinical characteristics and Holter indices across sex groups showed significant differences in males, particularly in age, maximum heart rate, and minimum heart rate (P < 0.05). In females, significant intergroup differences were observed in VPC burden (P < 0.05).
Conclusion: Although no significant sex differences were observed in the correlation between PVC frequency and HR, the study suggests a potential gender influence on VPC characteristics. These findings may inform future research and have implications for the development of sex-specific diagnostic and therapeutic strategies for PVCs.

Keywords: premature ventricular contractions, autonomic nervous system, Holter monitoring, heart rate variability