title: Sustained left ventricular tachycardia terminated by dipyridamole: cyclic AMP-mediated triggered activity as a possible mechanism.
abstract: Sustained VT in two patients was terminated by intravenous administration of dipyridamole, an adenosine transport inhibitor. VT was induced by rapid atrial or ventricular pacing, isoproterenol, or dibutyryl cyclic AMP infusion, or exercise. VT also was aborted by adenosine triphosphate or acetylcholine injection, or by vagal stimulation. VT was terminated or prevented by verapamil or propranolol. In addition, arrhythmias were prevented by oral administration of dipyridamole. These results suggest that VT is due to cyclic AMP-mediated triggered activity and that inhibition by dipyridamole may be due to a reduction in the intracellular concentration of cyclic AMP.
authors.affiliation: Third Department of Internal Medicine, Showa University School of Medicine, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kobayashi
authors.forename: S
authors.initials: S
authors.lastname: Kikushima
authors.forename: K
authors.initials: K
authors.lastname: Tanno
authors.forename: K
authors.initials: K
authors.lastname: Kurano
authors.forename: T
authors.initials: T
authors.lastname: Baba
authors.forename: T
authors.initials: T
authors.lastname: Katagiri
mesh_terms: D000109:Acetylcholine; D000293:Adolescent; D005117:Cardiac Complexes, Premature / Q000188:drug therapy; D000242:Cyclic AMP / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D004176:Dipyridamole / Q000494:pharmacology / Q000627:therapeutic use*; D004562:Electrocardiography / Q000187:drug effects; D015716:Electrocardiography, Ambulatory; D005080:Exercise Test; D005500:Follow-Up Studies; D006801:Humans; D007545:Isoproterenol; D008297:Male; D008875:Middle Aged; D017180:Tachycardia, Ventricular / Q000188:drug therapy* / Q000503:physiopathology; D016277:Ventricular Function, Left / Q000187:drug effects / Q000502:physiology
chemical_list: D004176:Dipyridamole; D000242:Cyclic AMP; D007545:Isoproterenol; D000109:Acetylcholine