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Abstract

Objective: To determine the effects of age and gender on heart rate variability in patients with heart failure.
Study Design: Cross sectional analytical study.
Place and Duration of Study: Department of Clinical Cardiac Electrophysiology Armed Forces Institute of Cardiology/National Institute of Heart Diseases, Rawalpindi from April 2013 to August 2013.
Material and Methods: 47 patients with the diagnosis of chronic heart failure of either sex, having age more than 19 years and with left ventricular ejection fraction equal to or less than 40 % were included in the study. All these patients underwent Holter ECG monitoring for 48 hours using DMS 300-4A and DMS 300-7A, Holter recorders. Statistical time domain measures of heart rate variability i.e. SDNN, SDNNi, SDANN, RMSSD, pNN50 were analyzed.
Results: There were 35 male (74.5%) and 12 female (25.5%) patients with mean age of 54.68±16.79 years. Mean values of SDNN, SDANN, SDNNi, RMSSD, and pNN50 were 79.96 ms, 72.26 ms, 36.60 ms, 29.94 ms and 8.85 % respectively. There was no difference of heart rate variability between males and females (p-value > 0.05). Age was negatively correlated with all the domains of heart rate variability, however, the correlation wassignificant only for SDNN and SDANN (p-value < 0.05).
Conclusion: Heart rate variability reduces with advancing age irrespective of the gender reflecting increased likelihood for developing ventricular arrhythmias in the predisposed patients.