Dominant R wave in V1
More common causes
Left ventricular hypertrophy
Wolff-Parkinson-White syndrome
Myocardial infarction
Pulmonary embolism
Less common causes
Right bundle branch block
Right ventricular hypertrophy
Myotonic dystrophy
Hypertrophic cardiomyopathy
Arrhythmogenic right ventricular dysplasia
Duchenne muscular dystrophy
Ebstein's anomaly
Uncommon causes
Dextrocardia
Posterior myocardial infarction