title: Chronotropic effects of cilostazol, a new antithrombotic agent, in patients with bradyarrhythmias.
abstract: Whether phosphodiesterase inhibitors increase the heart rate in patients with bradyarrhythmias is not known. We attempted to determine whether the oral phosphodiesterase inhibitor cilostazol exhibits beneficial chronotropic effects in patients with symptomatic bradyarrhythmias. Twenty patients comprising eight with bradycardic atrial fibrillation, eight with sick sinus syndrome, and four with Wenckebach-type atrioventricular block, whose 24-h total heart-beat count was < or =70,000 beats and whose maximal RR interval was > or =2.5 s, were enrolled. Holter recordings (24-h) were made before and 2 weeks after oral daily administration of 200 mg of cilostazol. Cilostazol increased the 24-h total heart-beat count from 77,429 +/- 11,168 to 107,981 +/- 13,536 (95% confidence interval, 24,605-36,497; p < 0.0001), the minimal heart rate from 33 +/- 9 47 +/- 13 beats/min (95% confidence interval, 9-19 beats/min; p < 0.0001), and the maximal RR interval from 3,149 +/- 1,018 to 2,087 +/- 601 ms (95% confidence interval, -1,517 to -608 ms; p = 0.0001). Only two patients had headaches as adverse effects. In conclusion, cilostazol had a beneficial positive chronotropic effect in patients with bradyarrhythmias, especially with bradycardic atrial fibrillation and sick sinus syndrome.
authors.affiliation: First Department of Internal Medicine, Nippon Medical School, Tokyo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Atarashi
authors.forename: Y
authors.initials: Y
authors.lastname: Endoh
authors.forename: H
authors.initials: H
authors.lastname: Saitoh
authors.forename: H
authors.initials: H
authors.lastname: Kishida
authors.forename: H
authors.initials: H
authors.lastname: Hayakawa
mesh_terms: D000284:Administration, Oral; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000188:drug therapy* / Q000503:physiopathology; D001281:Atrial Fibrillation / Q000188:drug therapy; D001919:Bradycardia / Q000188:drug therapy; D000077407:Cilostazol; D004562:Electrocardiography / Q000187:drug effects; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D006327:Heart Block / Q000188:drug therapy; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010726:Phosphodiesterase Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D011446:Prospective Studies; D012804:Sick Sinus Syndrome / Q000188:drug therapy; D013777:Tetrazoles / Q000008:administration & dosage / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D005343:Fibrinolytic Agents; D010726:Phosphodiesterase Inhibitors; D010975:Platelet Aggregation Inhibitors; D013777:Tetrazoles; D000077407:Cilostazol