Cardioprotective effects of carbocromen in awake and anesthetized dogs with amitriptyline poisoning.
We studied the effects of the antianginal drug carbocromen (4 mg/kg bolus plus 80 micrograms/kg/min i.v.) on amitriptyline (400 micrograms/kg/min i.v.) toxicity. In anesthetized dogs, amitriptyline increased heart rate, left ventricular (LV) end-diastolic pressure, and the PR and QT intervals, the QRS complex, and the S-T segments of the peripheral electrocardiogram. Blood pressure, LV pressure, and LV dP/dtmax fell considerably. Survival time was 37 +/- 4 min in amitriptyline-treated dogs and 64 +/- 3 min (p less than 0.05) in those receiving amitriptyline plus carbocromen. The amount of amitriptyline consumed until death increased from 14.8 to 25.6 mg/kg (p less than 0.05) with carbocromen. In conscious dogs, the hemodynamic impact of intraatrial amitriptyline was similar to that in anesthetized animals, and changes in stroke volume resembled those of dP/dt. Cardiac output was not altered, and peripheral resistance decreased moderately. Carbocromen prevented most of the typical amitriptyline effects on the heart and circulation. Sustained ventricular arrhythmia occurred at 29 +/- 4 min with amitriptyline infusion but was delayed to 58 +/- 3 min (p less than 0.05) when carbocromen was added. These experiments demonstrate (a) amitriptyline intoxication produced ventricular tachyarrhythmia and cardiac failure if high agent concentrations were achieved; (b) these rhythm disorders were associated with slowing of intraventricular conduction, which could be enhanced by carbocromen; and (c) carbocromen might be an effective therapy for amitriptyline-caused arrhythmia with cardiovascular collapse.
V B
VB
Fiedler
H
H
Göbel
R E
RE
Nitz
D000639:Amitriptyline / Q000008:administration & dosage / Q000506:poisoning*; D000758:Anesthesia; D000818:Animals; D002302:Cardiac Output / Q000187:drug effects; D002866:Chromonar / Q000627:therapeutic use*; D003374:Coumarins / Q000627:therapeutic use*; D004285:Dogs; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D007263:Infusions, Parenteral; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects; D013318:Stroke Volume / Q000187:drug effects; D014655:Vascular Resistance / Q000187:drug effects
D003374:Coumarins; D000639:Amitriptyline; D002866:Chromonar