Physical exercise promotes structural heart adaptation and increased parasympathetic autonomous activity in athletes. Some reports indicate that sinus bradycardia can promote occurrence of arrhythmias in athletes. AIM: The aim of this study was to compare the 12-lead surface ECG findings and arrhythmias/conduction disturbances detected in ambulatory ECG monitoring (AECG) between amateur athletes and healthy subject and to investigate relationship between bradycardia and arrhythmias. MATERIALS AND METHODS: Studied population included 34 athletes (29M, 5F, av. age 29±8yrs) and a control group of 34 healthy volunteers (29M, 5F, av. age 30±8yrs). 12-lead surface ECG and 24-hour AECG were performed in order to evaluate heart rate and arrhythmia/conduction disturbances in two groups. RESULTS: The athletes group was characterized by lower heart rate (med.59 vs.70 bpm, p<0.001), longer PR interval (med. 174 vs. 150 msec, p=0.007) and longer QTcF interval (med. 403 vs. 395 msec, p=0.026), with no statistically difference in QRS duration (med. 99 vs. 102 msec, p=0.699). Voltage criteria of LVH were observed in 10/34 (29%) of athletes and in 1 (2.94%) healthy subject. Four athletes (12%) showed first degree AV block. Similarly to ECG findings, AECG showed lower HR values (med. 66 vs.74 bpm, p<0.001) in athletes than in healthy subjects. Sinus bradycardia (<60bpm) was observed in 26% of athletes and 0% of controls (p=0.042). Ventricular arrhythmia was observed in 62% of athletes and 50% of healthy controls (p=0.464). No difference in occurrence of APBs was observed between studied groups (88% vs. 91%). Differences between occurrence of arrhythmias in athletes with lower HR (<60bpm) compared to those with higher did not reach statistical significance (VPBs: 6/9 vs. 15/25, p = 0.963; APBs: 9/9 vs 21/29, p = 0.5). CONCLUSIONS: Bradycardia does not promote ventricular neither atrial arrhythmias in athletes.
Physical exercise promotes structural heart adaptation and increased parasympathetic autonomous activity in athletes. Some reports indicate that sinus bradycardia can promote occurrence of arrhythmias in athletes. AIM: The aim of this study was to compare the 12-lead surface ECG findings and arrhythmias/conduction disturbances detected in ambulatory ECG monitoring (AECG) between amateur athletes and healthy subject and to investigate relationship between bradycardia and arrhythmias. MATERIALS AND METHODS: Studied population included 34 athletes (29M, 5F, av. age 29±8yrs) and a control group of 34 healthy volunteers (29M, 5F, av. age 30±8yrs). 12-lead surface ECG and 24-hour AECG were performed in order to evaluate heart rate and arrhythmia/conduction disturbances in two groups. RESULTS: The athletes group was characterized by lower heart rate (med.59 vs.70 bpm, p<0.001), longer PR interval (med. 174 vs. 150 msec, p=0.007) and longer QTcF interval (med. 403 vs. 395 msec, p=0.026), with no statistically difference in QRS duration (med. 99 vs. 102 msec, p=0.699). Voltage criteria of LVH were observed in 10/34 (29%) of athletes and in 1 (2.94%) healthy subject. Four athletes (12%) showed first degree AV block. Similarly to ECG findings, AECG showed lower HR values (med. 66 vs.74 bpm, p<0.001) in athletes than in healthy subjects. Sinus bradycardia (<60bpm) was observed in 26% of athletes and 0% of controls (p=0.042). Ventricular arrhythmia was observed in 62% of athletes and 50% of healthy controls (p=0.464). No difference in occurrence of APBs was observed between studied groups (88% vs. 91%). Differences between occurrence of arrhythmias in athletes with lower HR (<60bpm) compared to those with higher did not reach statistical significance (VPBs: 6/9 vs. 15/25, p = 0.963; APBs: 9/9 vs 21/29, p = 0.5). CONCLUSIONS:Bradycardia does not promote ventricular neither atrial arrhythmias in athletes.