Sotalol hydrochloride (Betapace): a new antiarrhythmic drug.

Sotalol hydrochloride (Betapace), recently released by the Food and Drug Administration for general use, is used to treat a variety of ventricular and supraventricular tachyarrhythmias. The drug's dominant action is the result of combined nonselective beta-adrenergic antagonism (Class II effect) and monophasic action potential duration prolongation in all cardiac tissues (Class III effect). It causes less left ventricular depression than propranolol and has a low incidence of toxicity. It is a useful addition to the antiarrhythmic drug armamentarium. This article reviews the drug's pharmacokinetic, pharmacodynamic and electrophysiologic properties, clinical uses and potential side effects. Reports on the drug's use as an antianginal and antihypertensive agent are also discussed.

Safety and efficacy of sotalol in patients with drug-refractory sustained ventricular tachyarrhythmias.

The safety and efficacy of oral sotalol, an investigational beta-adrenergic blocker with class III antiarrhythmic drug properties, were examined in a multicenter study in 236 patients with sustained ventricular tachyarrhythmias. In 104 patients, the index arrhythmia was a cardiac arrest, and all patients had undergone at least 3 previous unsuccessful antiarrhythmic trials (mean = 5 per patient). In the 106 patients assessed by programmed electrical stimulation, sotalol completely suppressed induction of ventricular tachycardia (VT) in 33 (31%) and rendered VT slower (greater than 100 ms prolongation of cycle length) or more difficult to induce in 29 (27%). Using continuous 24-hour ambulatory monitoring methods, sotalol complete- and partial-response rates were 51 and 12%, respectively. Of the 236 acute-phase patients, 151 were discharged receiving long-term sotalol therapy. The median sotalol dose was 480 mg/day. At a mean follow-up of 346 +/- 92 days, 27 patients (18%) had recurrence of sustained arrhythmia; 9, sudden death; 11, sustained VT; 5, automatic defibrillator discharge; and 2, syncope. Adverse effects forced discontinuation of therapy in 10 patients (7%): 6 secondary to symptomatic bradyarrhythmia, 2 due to refractory heart failure, 1 due to torsades de pointes, and 1 from bronchospasm. Life-table analysis of sotalol's overall long-term efficacy at 6, 12 and 18 months were 80, 76 and 72%, respectively. Although mean follow-up was short (less than 1 year), neither acute-phase programmed stimulation nor 24-hour ambulatory monitoring responses were significantly predictive of subsequent arrhythmic outcome. Proarrhythmia was documented in 18 patients (7%), 17 during the acute phase and 1 during long-term follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Patients with heart rhythm disturbances: variables associated with increased psychologic distress.

The spectrum of psychologic distress in patients with serious heart rhythm disturbances (HRD) has not been well defined. A survey of personal and clinical background data and general psychologic status was made of 136 patients with serious HRD defined as sustained or symptomatic ventricular tachycardia or fibrillation. Two questionnaires were used: the SCL-90-R, a standard self-report symptom inventory of present psychologic status, and a functional capacity and occupational status questionnaire developed by us. Of the 105 respondents, 89 completed both questionnaires, the results of which form the basis of this report. The patients with HRD were found to have significantly elevated SCL-90-R scores reflective of an increase in overall psychologic distress (Global Severity Index, Positive Symptom Distress Index, and Positive Symptom Total) as well as significantly higher scores on the specific constructs. Within the HRD population, univariate analysis revealed three variables significantly correlated with increased psychologic distress: (1) requiring long-term antiarrhythmic medication, (2) being forced to modify work status, and (3) having more advanced cardiac impairment. Patients who had two or more of these variables, termed risk factors, reported significantly more symptoms and greater psychologic distress than those with zero or one risk factor. We conclude that patients with serious HRD have greater psychologic distress than do normal subjects. Within the HRD group, patients requiring long-term medical treatment for their arrhythmia, those forced to modify work status, and those with more advanced cardiac impairment are at greater risk for emotional sequelae, and patients with two or more of the identified risk factors are more likely to have elevated psychologic distress.(ABSTRACT TRUNCATED AT 250 WORDS)