This study was undertaken in an attempt to investigate the hypothesis that a single-lead electrocardiogram taken from the right precordium (V3R) on a mass survey basis could detect a large proportion of operable congenital heart defects associated with right ventricular hypertrophy (RVH). These defects would include atrial septal defect, pulmonic stenosis, tetralogy of Fallot, "atypical" patent ductus arteriosus, and some varieties of ventricular septal defect.
The V3R lead was chosen as the single lead for study in accord with the findings of Sokolow and Lyon8 and of Katz et al.,2 who have demonstrated that right precordial leads seem to be the most sensitive indicators of RVH. Single leads have been used previously on ECG mass surveys.4 The single lead used has generally been standard Lead I and has been shown to be a rather poor indicator of heart disease when used as a