Variability in Heart Rate Recovery after Tredmill Testing and its Co-Relation with Body Mass Index in Patients with Normal ECG

Heart rate variability (HRV) has been established as a specific and sensitive non-invasive tool to study cardiac autonomic activity.1 AIM - To assess the factors affecting variability in heart rate recovery at one minute (HRR) after Treadmill test (TMT) in individuals with normal ECG and no preexisting cardiovascular diseases. Correlation of impaired HRR (less than12) with body mass index (BMI) and association with resting heart rate (RHR) and reserve heart rate (ReHR). Method The study was conducted in a tertiary care hospital in India over a period of 2 yrs.138 subjects between age of 18yr to 60yr were taken by simple random sampling. Data was analysed by stata software and chi-square test, multivariate regression analysis was used to find association of variables. Result Subjects with BMIgreater than25kg/m2 (overweight and obese) were found to be strongly associated with impaired heart rate recovery (p-value- 0.02, adjusted odds ratio-8.233). Conclusion- obesity is strong risk factor for impaired HRR and autonomic dysfunction. As delayed HRR is independent risk factor for coronary artery disease as well as a predisposing factor for arrhythmias and sudden death in obese patients, 2 This study was done to assess the various factors associated with impaired HRR so that preventive measure can be taken for cardiovascular accidents.