Wenckebach block in the distal conduction system.
D000368:Aged; D002036:Bundle of His; D002037:Bundle-Branch Block / Q000175:diagnosis; D004562:Electrocardiography; D006327:Heart Block / Q000175:diagnosis* / Q000209:etiology; D006329:Heart Conduction System; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial / Q000009:adverse effects