Management of Cardiac Arrhythmias with Tiapamil

Abstract

37 patients with either chronic atrial fibrillation (AF), atrial premature beats (APBs) or ventricular premature beats (VPBs) received tiapamil as antiarrhythmic treatment. Tiapamil reduced A-V conduction by an average 20% in the group with AF (10 patients), the magnitude of response being dependent on the initial ventricular rate. In 3 of the 7 patients with APBs, the frequency of ectopic beats was reduced following a single i.v. injection of 1 mg/kg tiapamil. In patients with VPBs (n = 20), tiapamil (i.v. injection of 1 mg/kg followed by 4-hour i.v. infusion of 50 µg/kg/min in 10 patients) reduced ectopic beats by 30-50% in 6 cases, these all being patients who had not responded to previous antiarrhythmic therapy. The antiarrhythmic effect was maintained by i.v. infusion of 50 µg/kg/min for 4 h. The antiarrhythmic effect of tiapamil consists essentially in slowing A-V conduction and reducing chronic VPBs.

Tiapamil

“…Tiapamil was also effective in reducing chronic atrial fibrillation and atrial premature beats. In the same study, intravenous tiapamil (1 mg/kg) caused a 3650% reduction in ventricular premature beats in 6 of 11 patients who had not responded to previous antiarrhythmic therapy (5). In patients with coronary artery disease and/or previous myocardial infarctions, a significant reduction in exercise-induced ventricular premature beats was also observed after intravenous tiapamil (6).…”

Class IV Antiarrhythmic Agents: New Compounds Using an Old Strategy

“…AV CT was increased and the frequency of atrial ectopic beats was reduced. Moreover, ectopic beats were reduced by 30-50 % in 6 out of 20 cases in patients with ventricular premature beats previously not responding to antiarrhythmic therapy [269]. In a small study tiapamil effectively restored SR and prevented tachycardias in patients with recurrent PSVT except in those with retrograde conduction involving an accessory pathway [270].…”

“…There are no human data about the antiarrhythmic actions of anipamil only the systolic and diastolic BP reducing [285] and anti ischemic effects of the drug were documented [286]. [239] Verapamil / 3 x 120 mg daily for at least 5 half-lives to load reduced VT in approximately 2/3 of the patients in idiopathic VT of left bundle branch block-like morphology [240] Verapamil / 5-20 mg/min intravenously terminated paroxysmal sustained monomorphic VT, repetitive non-sustained VT or premature ventricular contractions [241] Verapamil / 0.2 mg/kg intravenously reduced the number of premature ventricular complexes in catecholaminergic polymorphic VT carrying a cardiac ryanodine receptor mutation [244] Verapamil / 0.25-1.0 mg intracoronary terminated all reperfusion-induced arrhythmias except for VFs and reduced various ischemia-induced arrhythmias [246] Verapamil / up to 20 mg in 1 mg/min increments, intravenously, titrated to effect in supraventricular tachyarrhythmia VR was reduced below 100 beats/min in patients within 72 hours with of AMI, conversion to SR was done in most patients with AFL [218] Verapamil / 240 mg SR tablet daily right ventricular outflow tract tachycardia was terminated [247] D600 / 100 mg per os decreased the HR for 10 hours in AF [259] Tiapamil / 1 mg/kg intravenously reduced VR and rhythm was converted to SR in some cases in AFL, AF or PSVT patients [268] Tiapamil / 1 mg/kg or 50 µg/kg/min for 4 h intravenously ectopic beats were reduced in patients with atrial and ventricular premature beats, AV CT was increased in chronic AF [269] Tiapamil / a bolus of 2 mg/kg intravenously, 1x 1.2-1.5 g daily restored SR and prevented tachycardias in patients with recurrent PSVT having no accessory pathway [270] Tiapamil / 3 x 200 mg daily per os positive effects in supraventricular and ventricular extrasystoles [272] Tiapamil / 1 mg/kg then 50 µg/kg/min for 4 h intravenously reduced ischemia related arrhythmias, decreased the VR in patients with AF [273] Tiapamil / 1 mg/kg then 25 µg/kg/min intravenously reduced the number of premature ventricular contractions, supraventricular extra beats, HR to less than 90 beats/min and exercise-induced extrasystoles in patients with or after AMI [275] [276] [277] [278] Tiapamil / 1-1.5 mg/kg intravenously reduced intra-and postoperative cardiac arrhythmias such as AF, supraventricular paroxysmal tachycardia and in VEBs [279] 9.2. Benzothiazepines Diltiazem Animal studies with diltiazem Antiarrhythmic actions of diltiazem on both ischemia-and reperfusion-induced arrhythmias were described in rats [287], …”

Verapamil and tiapamil in prevention of ventricular fibrillation in pigs with coronary ligation. Comparative effects on left ventricular function.

“…'0 In another study with patients, tiapamil 13 mg/kg given as an infusion during a 4-hour period reduced ventricular ectopic beats. 26 LV dP/dtmax was used as an index of LV mechanical function in our study. In patients, this index is useful in assessing acute changes in the inotropic state.27 In open-chest animals, both preload and afterload can influence LV dP/dtmax with increases in both variables increasing LV dP/dtmax.28 In our experiments, the higher doses of verapamil caused LVEDP to rise, which could have increased LV dP/dtmax, whereas the fall in both blood pressure and heart rate could have caused LV dP/dtmax to fall.…”