Letter: Concealed ventricular ectopics.
D001145:Arrhythmias, Cardiac / Q000209:etiology* / Q000503:physiopathology; D004562:Electrocardiography; D006329:Heart Conduction System / Q000503:physiopathology; D006352:Heart Ventricles; D006801:Humans; D008297:Male; D008875:Middle Aged