Background: Scuba diving imposes uncommon environmental stresses. This study assesses the effects of recreational scuba diving on the electrocardiogram (ECG) and echocardiogram and compares them with those of normal controls.
Methods: We studied 50 recreational scuba divers and 50 age-matched and sex-matched normal control subjects. Each subject had a medical history, physical examination, resting 12-lead ECG, and transthoracic echocardiogram.
Results: Electrocardiographic findings occurring significantly more frequently in scuba divers than in controls were sinus bradycardia, sinus arrhythmia, QRS duration (> or = 0.10 sec, right axis duration and R > or =S in V2. The mean right ventricular internal dimension (RVID) was significantly larger in divers than in controls. High-normal RVID (2.0 to 2.3 cm) occurred significantly more regularly in divers than in controls (10 vs 1).
Conclusion: Recreational scuba diving produced right ventricular alterations characterized by chamber dilation and electrocardiographic signs of right ventricular hypertrophy, sinus bradycardia, and arrhythmia.