Carbamazepine-induced sinus node dysfunction

Carbamazepine, a drug used for the treatment of epilepsy and neuralgias, may exert hazardous effects on the cardiac conduction system. We report such a case of symptomatic brady-arrhythmia occurring in a 43-years-old male while on therapy with carbamazepine. Additionally, a literature review is made of previous cases of carbamazepine-induced sinus mode, AV node and His-Purkinje conduction disturbances

Hipertensão arterial e arritmias ventriculares complexas: evoluçäo após tratamento de longo prazo da pressäo arterial / Hypertension and complex ventricular arrhythmias: evolution following a long-term blood pressure treatment

PURPOSE--To evaluate the effects of long-term antihypertensive treatment in the frequency as well as in the complexity of ventricular arrhythmias in arterial hypertension. METHODS--Twenty three patients, 14 males and 11 whites, with mean age of 46 years, were submitted to 24 hours ambulatory electrocardiographic monitoring and echocardiographic studies before and 9 months after antihypertensive treatment. RESULTS--There was no significant serum potassium level alteration, but significant reductions of both systolic (from 192 +/- 29mmHg to 161 +/- 25mmHg) and diastolic (from 122 +/- 17mmHg to 99 +/- 16mmHg) blood pressure. Left ventricular percent of fiber shortening significantly increased, even though only from 26 +/- 9 per cent to 30 +/- 9 per cent, and end-systolic wall stress did not change at all (before 258 +/- 94 10(3) dyn/cm2, after 255 +/- 101 10(3) dyn/cm2). Left ventricular mass index showed significant but also a discrete reduction from 211 +/- 75g/m2 to 196 +/- 70g/m2. Ambulatory electrocardiographic monitoring did not show any significant decrease in neither ventricular ectopic beats nor in couplets. Non-sustained ventricular tachycardia episodes remained unchanged too. Four out of 8 patients with more than 30 ventricular ectopic beats per hour reduced it by more than 70 per cent. On the other hand, the number of patients with couplets was reduced from 10 to 8 whilst those with non-sustained ventricular tachycardia increased from 5 to 7. Furthermore, in 7 patients reevaluated 24 months thereafter results were not expressively dissimilar. CONCLUSION--In hypertensive patients with either severe degree of left ventricular hypertrophy or myocardial dysfunction, long-term blood pressure treatment that produce no impressive changes in these abnormalities also do not modify complex ventricular arrhythmias, in spite of a great reduction in the increase blood pressure

Low dose amiodarone in refractory tachyarrhythmias.

Fifty patients with drug resistant tachyarrhythmias were treated with amiodarone for 6-22 months; 16 for recurrent ventricular tachycardia (VT), 2 for VT followed by ventricular fibrillation (VF), 14 for complex ventricular ectopics, and 18 for supraventricular tachyarrhythmias (SVT). Amiodarone was administered in a dose much lower than that used in western trials. The actual incidence of successful amiodarone therapy was 81.2% at 22 months for patients with VT. Among the patients with SVT, 88.6% patients were successfully treated for 22 months (range 3-22 months). Amiodarone toxicity appeared in 22 of 50 patients (44%) treated for more than 12 weeks. Withdrawal of therapy was required in 4 patients. Despite the lower dose, clinical efficacy and onset of action were comparable to the western experience.