title: Parasystolic rhythm after implantation of a demand pacemaker.
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005117:Cardiac Complexes, Premature / Q000209:etiology* / Q000628:therapy; D004562:Electrocardiography; D006327:Heart Block / Q000628:therapy*; D006339:Heart Rate; D006801:Humans; D008297:Male; D010138:Pacemaker, Artificial