Efficacy and safety of intravenous sotalol for termination of paroxysmal supraventricular tachycardia. The Sotalol Versus Placebo Multicenter Study Group

Clinical Pharmacology-Driven Translational Research to Optimize Bedside Therapeutics of Sotalol Therapy

Oral sotalol, used in adults for sinus rhythm control, is initiated at 80 mg b.i.d. and titrated to a maximum safe dose. The US Food and Drug Administration recommends monitoring the corrected QT interval (QTc ) for at least 3 days, until steady-state exposure of the drug is reached, before patient discharge, which can significantly impact the total cost of treatment. The objectives of this research were to design an accelerated intravenous sotalol loading and maintenance therapy that will reduce the hospital length of stay and to also evaluate the pharmacoeconomic impact in a hospital setting. Pharmacokinetic simulations of sotalol plasma concentrations vs. times profiles were performed to determine the optimal intravenous/oral transition regimen. A cost minimization analysis from the health sector perspective was conducted to assess the cost savings for these proposed accelerated regimens. For a chosen target dose of 120 mg b.i.d., two infusions of 40 mg over 1 hour and 20 mg over 0.5 hour, each followed up by an evaluation of QTc , can be administered followed immediately by the target oral maintenance dose of 120 mg at the end of the second infusion. Consequently, steady-state exposure and, therefore, steady-state QTc are obtained on the first day of therapy, facilitating an earlier hospital discharge. Two and 1-day mean total cost of -$3,123 (95% confidence interval (CI), -$3,640, -$2,607) -$4,820 (95% CI, -$5,352, -$4,288) were observed for this strategy, respectively. We are proposing an intravenous to oral transition strategy for sotalol that has the potential to significantly reduce cost and increase patient convenience.

Does Sotalol Still Have a Role in the Management of Arrhythmias?

Despite proven effectiveness in treating tachyarrhythmias, sotalol is proarrhythmic and can cause torsades de pointes. Given the emergence of studies that show no benefit from rhythm control strategies in managing atrial fibrillation, as well as the introduction of nonpharmacological approaches to treating arrhythmias, we felt it necessary to ascertain if there was any role for sotalol given its side effects. Review of the literature regarding sotalol use in the prevention and treatment of supraventricular and ventricular tachyarrhythmias seems to show that more effective and safer agents and nonpharmacological alternatives are currently available. However, sotalol still seems to be useful in preventing supraventricular tachyarrhythmias postcardiac surgery and in reverting hemodynamically stable sustained ventricular tachycardias in the setting of coronary artery disease. Its role in the prevention of tachyarrhythmias in the setting of arrhythmogenic right ventricular cardiomyopathy requires further investigation.

Adenosine versus intravenous calcium channel antagonists for supraventricular tachycardia

BACKGROUND

People with supraventricular tachycardia (SVT) frequently are symptomatic and present to the emergency department for treatment. Although vagal manoeuvres may terminate SVT, they often fail, and subsequently adenosine or calcium channel antagonists (CCAs) are administered. Both are known to be effective, but both have a significant side effect profile. This is an update of a Cochrane review previously published in 2006.

OBJECTIVES

To review all randomised controlled trials (RCTs) that compare effects of adenosine versus CCAs in terminating SVT.

SEARCH METHODS

We identified studies by searching CENTRAL, MEDLINE, Embase, and two trial registers in July 2017. We checked bibliographies of identified studies and applied no language restrictions.

SELECTION CRITERIA

We planned to include all RCTs that compare adenosine versus a CCA for patients of any age presenting with SVT.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as expected by Cochrane. Two review authors independently checked results of searches to identify relevant studies and resolved differences by discussion with a third review author. At least two review authors independently assessed each included study and extracted study data. We entered extracted data into Review Manager 5. Primary outcomes were rate of reversion to sinus rhythm and major adverse effects of adenosine and CCAs. Secondary outcomes were rate of recurrence, time to reversion, and minor adverse outcomes. We measured outcomes by calculating odds ratios (ORs) and assessed the quality of primary outcomes using the GRADE approach through the GRADEproGDT website.

MAIN RESULTS

We identified two new studies for inclusion in the review update; the review now includes seven trials with 622 participants who presented to an emergency department with SVT. All included studies were RCTs, but only three described the randomisation process, and none had blinded participants, personnel, or outcome assessors to the intervention given. Moderate-quality evidence shows no differences in the number of people reverting to sinus rhythm who were treated with adenosine or CCA (89.7% vs 92.9%; OR 1.51, 95% confidence interval (CI) 0.85 to 2.68; participants = 622; studies = 7; I² = 36%). Low-quality evidence suggests no appreciable differences in major adverse event rates between CCAs and adenosine. Researchers reported only one case of hypotension in the CCA group and none in the adenosine group (0.66% vs 0%; OR 3.09, 95% CI 0.12 to 76.71; participants = 306; studies = 3; I² = 0%). Included trials did not report length of stay in hospital nor patient satisfaction.

AUTHORS' CONCLUSIONS

Moderate-quality evidence shows no differences in effects of adenosine and calcium channel antagonists for treatment of SVT on reverting to sinus rhythm, and low-quality evidence suggests no appreciable differences in the incidence of hypotension. A study comparing patient experiences and prospectively studied adverse events would provide evidence on which treatment is preferable for management of SVT.

Sotalol

Sotalol is effective for treating atrial fibrillation (AF), ventricular tachycardia, premature ventricular contractions, and supraventricular tachycardia. Racemic (DL) sotalol inhibits the rapid component of the delayed rectifier potassium current. There is a near linear relationship between sotalol dosage and QT interval prolongation. However, in dose ranging trials in patients with AF, low-dose sotalol was not more effective than placebo. Orally administered sotalol has a bioavailability of nearly 100%. The only significant drug interactions are the need to avoid or limit use of concomitant drugs that cause QT prolongation, bradycardia, and/or hypotension.

Managing arrhythmias in the intensive care unit

Patients admitted to the intensive care unit (ICU) are at increased risk for cardiac arrhythmias, the most common of which can be subdivided into tachyarrhythmias and bradyarrhythmias. These arrhythmias may be the primary reason for ICU admission or may occur in the critically ill patient. This article addresses the occurrence of arrhythmias in the critically ill patient, and discusses their pathophysiology, implications, recognition, and management.

WITHDRAWN: Adenosine versus intravenous calcium channel antagonists for the treatment of supraventricular tachycardia in adults

BACKGROUND

Patients with paroxysmal supraventricular tachycardia frequently present to the Emergency Department. Where vagal manoeuvres fail, the two most commonly used drugs are adenosine and calcium channel antagonists. Both are known to be effective but both have a significant side-effect profile.

OBJECTIVES

To examine the relative effects of adenosine and calcium channel antagonists and, if possible, to determine which is most appropriate for the management of supraventricular tachycardia.

SEARCH METHODS

Studies were identified from The Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library, Issue 2, 2010, MEDLINE (1966 to May Week 1 2010) and EMBASE (1980 to 2010 week 19). The searches were originally run in June 2006 and updated and re-run in May 2010. Bibliographies of identified studies were also examined. No language restrictions were applied.

SELECTION CRITERIA

Randomised trials comparing adenosine and a calcium channel antagonist in patients of any age with supraventricular tachycardia, where one of the defined outcomes was reported. Outcomes of interest were: reversion rate, mortality, time to reversion, rate of relapse, major and minor adverse events, length of hospital stay and patient satisfaction.

DATA COLLECTION AND ANALYSIS

Two authors independently checked the results of searches to identify relevant studies. Dichotomous outcomes were reported as Peto Odds ratios and continuous outcomes as weighted mean differences.

MAIN RESULTS

A total of ten trials were identified (two new trials were identified through the updated search in May 2010), all of which used verapamil as the calcium antagonist. In the pooled analysis there was no significant difference in reversion rate between the two drugs. Time to reversion was slower for verapamil than adenosine in all studies that reported this outcome, but the data were not suitable for combining. Relapse rates were higher for adenosine compared with verapamil (OR 0.25, 95% CI 0.07 to 0.99. P=0.05). Minor adverse events such as nausea, chest tightness, shortness of breath and headache were reported much more frequently in patients treated with adenosine with 10.8 % of patients reporting at least one of these events, compared with 0.6% of those treated with verapamil (OR 0.15, 95% CI 0.09 to 0.26, P<0.001). Hypotension was reported exclusively in the verapamil treatment group (4/214), and occurred in none of the patients treated with adenosine (OR 10.8, 95% CI 1.46 to 80.22, P=0.02).

AUTHORS' CONCLUSIONS

Adenosine and verapamil are both effective treatments for supraventricular tachycardia in the majority of patients. There is a high incidence of minor but unpleasant side effects and a greater risk of relapse in patients treated with adenosine while some patients treated with verapamil may develop significant hypotension. Patients should be fully informed of these risks prior to treatment.

Adenosine versus intravenous calcium channel antagonists for the treatment of supraventricular tachycardia in adults

BACKGROUND

Patients with paroxysmal supraventricular tachycardia frequently present to the Emergency Department. Where vagal manoeuvres fail, the two most commonly used drugs are adenosine and calcium channel antagonists. Both are known to be effective but both have a significant side-effect profile.

OBJECTIVES

To examine the relative effects of adenosine and calcium channel antagonists and, if possible, to determine which is most appropriate for the management of supraventricular tachycardia.

SEARCH STRATEGY

Studies were identified from The Cochrane Central Register of Controlled Trials (CENTRAL), Issue 3 2006, MEDLINE (1966 to June 2006), Pre-MEDLINE and EMBASE (1980 to June 2006). Bibliographies of identified studies were also examined. No language restrictions were applied.

INCLUSION CRITERIA

randomised trials comparing adenosine and a calcium channel antagonist in patients of any age with supraventricular tachycardia, where one of the defined outcomes was reported. Outcomes of interest were: reversion rate, mortality, time to reversion, rate of relapse, minor adverse events, major adverse events, length of hospital stay and patient satisfaction. Major adverse events were defined as cardiac arrest, prolonged hypotension, symptomatic bradycardia requiring treatment and acute cardiac failure. Minor adverse events were any other reported event.

DATA COLLECTION AND ANALYSIS

Two reviewers independently checked the results of searches to identify relevant studies. Dichotomous outcomes were reported as Peto Odds ratios and continuous outcomes as weighted mean differences.

MAIN RESULTS

Eight trials were identified. In the pooled analysis there was no significant difference in reversion rate or relapse rate between the two drugs. Time to reversion was slower for verapamil than adenosine in all studies that reported this outcome, but the data were not suitable for combining. Minor adverse events such as nausea, chest tightness, shortness of breath and headache were reported much more frequently in patients treated with adenosine with 10.8 % of patients reporting at least one of these events, compared with 0.6% of those treated with verapamil (OR 0.15, 95% CI 0.09 to 0.26, P<0.001). There was no significant difference in the rate of major adverse events between the two groups, although hypotension was reported exclusively in the verapamil treatment group (3/166 patients treated with verapamil, 0/171 treated with adenosine).

AUTHORS' CONCLUSIONS

Adenosine and verapamil are both effective treatments for supraventricular tachycardia in the majority of patients. However, given the high incidence of minor but unpleasant side effects in patients treated with adenosine and the potential for hypotension with verapamil, patients should be fully informed of these risks prior to treatment.

Sotalol in treatment of pediatric cardiac arrhythmias

BACKGROUND

There is limited experience on sotalol use in the management of childhood arrhythmias. This study reviews the results of our experience with oral sotalol for treatment and prevention of tachyarrhythmias in children.

METHODS

The records of 62 patients (27 female, 35 male, mean age: 8.5+/-5.3 years) treated with sotalol for supraventricular or ventricular arrhythmias from 1994 to 1999 at our institution were reviewed. Demographic, clinical, echocardiographic, electrocardiographic (ECG), ambulatory ECG and electrophysiologic variables were collected.

RESULTS

Forty-two (63.6%) patients had re-entrant supraventricular tachycardia, eight patients (12.9%) had atrial tachycardia, one patient (1.6%) had junctional ectopic tachycardia, four patients (6.5%) had ventricular tachycardia, and seven patients (11.3%) had complex ventricular arrhythmias, as evidenced by surface or ambulatory ECG records; or revealed during the electrophysiological study. The mean sotalol dose was 3.9+/-1.2 mg/kg per day. In 15.5+/-13.9 months of sotalol use 50% (n=31) had complete relief of symptoms and/or arrhythmia and 29% (n=18) had partial relief. Sotalol was ineffective in 20% (n=13). Sotalol was more effective in re-entrant type supraventricular tachycardias (P=0.012). Sotalol was the first choice in 35.5% of patients. The sotalol therapy was initiated in inpatient settings in 40.3% (25 patients). Complications due to sotalol were seen in six patients (five patients developed bradycardia/pauses, and one patient had torsades de pointes) for which the sotalol dose was modified. In patients with sick sinus syndrome, a pacemaker was implanted and in another patient sotalol was stopped.

CONCLUSION

Sotalol, being an effective and safe drug particularly in children, is a good therapeutic alternative for the preventive treatment of childhood tachyarrhythmias.

Effects of intravenous dofetilide on induction of atrioventricular re-entrant tachycardia

OBJECTIVE

To assess the efficacy and safety of intravenous dofetilide in preventing induction of atrioventricular re-entrant tachycardia.

DESIGN

A multicentre, open, dose ranging trial. Fifty one patients with electrically inducible atrioventricular re-entrant tachycardia were allocated to one of five doses of dofetilide (1.5, 3, 6, 9, and 15 microgram/kg), two thirds of the dofetilide dose being given over a 15 minute loading period and the remainder over a 45 minute maintenance period.

MAIN OUTCOME MEASURE

Responders were defined as patients in whom dofetilide prevented reinduction of atrioventricular re-entrant tachycardia at the end of the infusion.

RESULTS

Intravenous dofetilide had no effect on tachycardia inducibility at the two lower doses (1.5 and 3 microgram/kg) but prevented the reinduction of tachycardia at the three higher doses (6, 9, and 15 microgram/kg) at a rate of 36% (11/31). There was a clear relation between plasma dofetilide concentrations and efficacy (p = 0.009). In non-responders, dofetilide increased the cycle length of induced atrioventricular re-entrant tachycardia. Dofetilide increased the atrial and ventricular effective refractory periods, as well as the antegrade and retrograde effective refractory period of the accessory pathway. Treatment related side effects were reported in four patients, one with a new sustained incessant supraventricular tachycardia.

CONCLUSIONS

Dofetilide shows promise as an agent for the prevention of atrioventricular re-entrant tachycardia in patients without structural heart disease.

Early postoperative arrhythmias after open-heart procedures in children with congenital heart disease

OBJECTIVE: Evaluation of occurrence, clinical course, necessity of treatment, and outcome of early postoperative cardiac arrhythmias after open-heart surgery. DESIGN: Prospective study. SETTING: Tertiary pediatric intensive care and pediatric cardiology unit. PATIENTS: All consecutive pediatric patients undergoing cardiac surgery on cardiopulmonary bypass were studied for the occurrence of cardiac arrhythmias during the whole perioperative hospital stay. Measurements: All patients had continuous electrocardiographic monitoring (with memory function) during the whole intensive care stay. A 24-hr Holter recording was done thereafter in patients with arrhythmias. RESULTS: Of 310 patients studied, 83 (27%) had postoperative arrhythmias. The occurrence rate was not different whether surgical access was by atriotomy or ventriculotomy (26% vs. 28%, respectively). Infants (39%) and cyanotic patients (36%) had a higher occurrence rate of arrhythmias (p <.05). Arrhythmias were more common after prolonged cardiopulmonary bypass time and with higher postoperative maximum troponin serum levels. In addition, patients with hemodynamically significant residual findings after correction had an increased occurrence rate of arrhythmias (18 of 43; 42%; p <.01). Of the 83 children with arrhythmias, 53 (64%) required specific antiarrhythmic treatment. The use of antiarrhythmic drugs was required in only 7 of these patients. Only one patient (1.2% of patients with arrhythmias) died from arrhythmia. No major complications resulting from arrhythmias occurred during the postoperative clinical course in the other patients. CONCLUSIONS: Although they occur frequently, postoperative arrhythmias after open-heart procedures in children are associated with low morbidity and mortality.

Supraventricular tachycardia

Supraventricular tachycardias (SVT) comprise those tachycardias that originate above the bifurcation of the bundle of His. They can be classified broadly as AV node dependent and AV node independent. The mechanism and clinical manifestation of SVTs, which is essential to their correct diagnosis, is reviewed. The therapeutic management of SVTs, including acute and chronic drug therapy and catheter ablation, is discussed also.

Meta-analysis of the Risk of Torsades de Pointes in patients treated with intravenous racemic sotalol

OBJECTIVE

Intravenous (IV) racemic sotalol is useful for the treatment of multiple tachydysrhythmias. The authors hypothesized that the risk of torsades de pointes (TdP) in patients treated with a single IV infusion of sotalol is lower than the 2-4% risk associated with chronic oral sotalol therapy.

METHODS

A MEDLINE search under the subject heading "sotalol" was made of all publications involving humans written in English or German from 1966 to October 1, 2000. A meta-analysis of all original reports including patients who were given a single infusion of at least 1.5 mg/kg or 100 mg of IV sotalol over 30 minutes or less was performed. Potential variables predictive of TdP were assessed. The primary outcome was the observation of TdP associated with IV sotalol infusion. Secondary measurements included hypotension, bradycardia, and worsening of congestive heart failure. All excluded studies and case reports were also examined for evidence of TdP associated with IV sotalol treatment.

RESULTS

The search included 1,005 publications. There were 37 reports in which 962 patients received IV sotalol and met the inclusion criteria. There was one report of self-terminating TdP lasting 10 seconds among the 962 patients included in the study. There was no report of TdP associated with only IV racemic sotalol administration in any of the excluded studies. If it is assumed that the risk of TdP is homogeneous in the population of patients treated with IV sotalol, then based on the 962 included patients, the rate of TdP is 0.1% (95% CI = 0.003% to 0.6%).

CONCLUSIONS

The overall risk of TdP in patients treated with a single infusion of IV sotalol is low compared with that in patients given chronic oral sotalol therapy.

Rate adaptive dual chamber pacing: inappropriate rate response due to pseudomalfunction of the QT biosensor

Inappropriate tachycardias may be observed in patients with DDDR pacemakers equipped with an activity sensor and a QT sensor due erroneous T wave sensing, provoked by drug treatment that prolongs cardiac repolarization.

Sotalol: An important new antiarrhythmic

Sotalol, the most recently approved oral antiarrhythmic drug, has a unique pharmacologic profile. Its electrophysiology is explained by nonselective beta-blocking action as well as class III antiarrhythmic activity (including fast-activating cardiac membrane-delayed rectifier current blockade), which leads to increases in action potential duration and refractory period throughout the heart and in QT interval on the surface electrocardiogram. Its better hemodynamic tolerance than other beta-blockers may be a result of enhanced inotropy associated with class III activity. Sotalol's ability to suppress ventricular ectopy is similar to that of class I agents and better than that of standard beta-blockers. Unlike class I agents, its use in a postinfarction trial was not associated with increased mortality rate. Therapeutically, it has shown superior efficacy for prevention of recurrent ventricular tachycardia and ventricular fibrillation, which was the basis for its approval. In a randomized study, the Electrophysiologic Study Versus Electrocardiographic Monitoring (ESVEM) trial, sotalol was associated with an increased in-hospital efficacy prediction rate (by Holter monitor or electrophysiologic study), reduced long-term arrhythmic recurrence rate with superior tolerance, and lower mortality rate than class I ("standard") antiarrhythmic drugs. Sotalol was 1 of 2 drugs selected for comparison with implantable defibrillators in the recent National Institutes of Health Antiarrhythmics versus Implantable Defibrillator (AVID) study. Sotalol appears to be a preferred drug for use with implantable defibrillators; unlike some other agents (eg, amiodarone) it does not elevate and, indeed, may lower defibrillation threshold. Although unapproved for this use, sotalol is active against atrial arrhythmias. It has shown efficacy equivalent to propafenone and quinidine in preventing atrial fibrillation recurrence, but it is better tolerated than quinidine and provides excellent rate control during recurrence. Sotalol's major side effects are related to beta-blockade and the risk of torsades de pointes (acceptably small if appropriate precautions are taken). Unlike several other antiarrhythmics (eg, amiodarone), it has no pharmacokinetic drug-drug interactions, is not metabolized, and is entirely renally excreted. Initial dose is 80 mg twice daily, with gradual titration to 240 to 360 mg/day as needed. The daily dose must be reduced in renal failure. On the basis of favorable clinical trials and practice experience, sotalol has shown a steadily growing impact on the treatment of arrhythmias during its 5 years of market availability, a trend that is likely to continue.

Absorption kinetics of oral sotalol combined with cisapride and sublingual sotalol in healthy subjects

AIMS

To study the absorption kinetics of sotalol following administration of different formulations. A formulation which results in fast absorption might be useful in the episodic treatment of paroxysmal supraventricular tachycardia (SVT), atrial fibrillation (Afib) or atrial flutter (Afl).

METHODS

In an open randomized crossover study seven healthy male volunteers were given an intravenous infusion of 20 mg sotalol, for assessing the absolute bioavailability, an oral solution containing 80 mg sotalol, an oral solution containing both 80 mg sotalol and 20 mg cisapride and an 80 mg sotalol tablet, which was taken sublingually.

RESULTS

The addition of cisapride decreased the time at which maximum serum concentrations were reached (tmax) from 2.79 (1.85-4.34) h to 1.16 (0.68-2.30) h (P=0.009) [95% CI: -2.59, -0.55] and increased the absorption rate constant (ka) from 0.49 (0.31-0.69) h(-1) to 1.26 (0.52-5.61) h(-1) (P=0.017). The absolute bioavailability of sotalol was reduced by cisapride from 1.00+/-0.15 to 0.70+/-0.26 (P=0.006), while maximum serum concentrations of both oral solutions were not significantly different. Compared with the sublingually administered tablet with a median tmax of 2.12 (0.89-3.28) h, the sotalol/cisapride oral solution gave a smaller tmax (p=0.009) [95% CI: -1.64, -0.36]. The ka of the sotalol/cisapride solution was significantly (P=0.010) larger than the ka of 0.56 (0.33-0.75) h(-1) found after sublingual administration of the tablet.

CONCLUSIONS

The sotalol/cisapride oral solution might be suitable for the episodic treatment of SVT, Afib or Afl.

Current role of pharmacologic therapy for patients with paroxysmal supraventricular tachycardia

Intravenous antiarrhythmic drugs will continue to have an important role in the acute management of SVT. Long-term antiarrhythmic drug therapy is often effective in preventing or reducing frequency and severity of arrhythmic episodes. The cost, adverse effects, and inconvenience of long-term drug therapy will result in the increasing use of curative ablation for most individuals with problematic SVT.

Efficacy and safety of sotalol in patients with refractory atrial fibrillation or flutter

Sotalol's usefulness in treatment of atrial fibrillation and atrial flutter is unproven. This study evaluated (1) the efficacy of sotalol in preventing recurrences of paroxysmal atrial fibrillation or atrial flutter and controlling ventricular rate (in chronic atrial fibrillation or relapse of paroxysmal atrial arrhythmias), (2) the safety of sotalol, and (3) predictors of sotalol efficacy. Thirty-three patients, 28 with paroxysmal and five with chronic atrial fibrillation or atrial flutter, received an average dose of 265 +/- 119 mg of oral sotalol per day. During a 10 +/- 12 month follow-up, recurrence rate for paroxysmal arrhythmia was 64%, with a 50% recurrence at 4.6 months. For patients with chronic atrial fibrillation, ventricular rates were well controlled with sotalol administration (136 +/- 33 beats/min versus 88 +/- 23 beats/min; p = 0.04). No patient with chronic atrial fibrillation converted to sinus rhythm during the study. Side effects necessitated sotalol discontinuation in three patients. By multivariate analysis, younger age, higher ejection fraction, and absence of hypertension independently predicted sotalol efficacy.

Efficacy and proarrhythmia of oral sotalol in pediatric patients

OBJECTIVES

This study sought to assess the efficacy of oral sotalol for various arrhythmias in pediatric patients and to evaluate the incidence of proarrhythmia and systemic side effects.

BACKGROUND

Sotalol is a beta-adrenergic blocking agent with additional class III antiarrhythmic properties. Experience in pediatric patients is limited. Data concerning the incidence of proarrhythmia in children are lacking.

METHODS

Seventy-one pediatric patients (mean age 7.3 years) with various supraventricular and ventricular tachyarrhythmias were treated with oral sotalol. All the patients were admitted to the hospital for initiation of sotalol therapy. Antiarrhythmic and proarrhythmic effects of sotalol were assessed by daily surface electrocardiograms (ECGs) during the in-hospital phase and by serial Holter monitoring.

RESULTS

Sotalol was either completely (27 [66%] of 41 patients) or partially effective (11 [27%] of 41) in 38 (93%) of 41 patients with supraventricular reentrant tachycardias. In patients with atrial flutter predominantly after operation for congenital heart disease, sotalol was effective in 84% of patients (completely in 9 of 19 and partially in 7 of 19). Ventricular tachycardia was completely (3 of 11) or partially (4 of 11) controlled in 64% of children. Proarrhythmia occurred in seven patients (10%) and consisted of symptomatic bradycardia from sinoatrial block and high grade atrioventricular (AV) block, respectively, in two children; asymptomatic high grade AV block in one; torsade de pointes in one; and relevant increased ventricular ectopic activity in three. Proarrhythmia required drug discontinuation in four patients. Mean duration of treatment for all patients was 18 months (range 1 to 40).

CONCLUSIONS

Sotalol was an effective antiarrhythmic drug for a wide range of pediatric tachyarrhythmias. The considerable number of patients with proarrhythmic effects indicates the need for initiation of treatment on an inpatient basis and close monitoring by serial Holter electrocardiography.

Sotalol: a new beta-adrenergic blocker for ventricular arrhythmias

Sotalol is a water-soluble, nonselective, beta-adrenergic blocker that was recently approved in oral form in the United States for the treatment of ventricular arrhythmias that are judged to be life-threatening. As a beta-blocker, sotalol is unique in having additional class-III antiarrhythmic activity. It is still not resolved whether sotalol is more effective than other beta-blockers in managing arrhythmias, but there are suggestions that it might possess greater antiarrhythmic and life-protecting activities than other types of antiarrhythmic drugs. The drug is well tolerated, but, because of its electrophysiologic activity, there is a small risk of proarrhythmia, specifically the development of polymorphic ventricular tachycardia and torsade de pointes.

Intravenous sotalol for the termination of supraventricular tachycardia and atrial fibrillation and flutter: a multicenter, randomized, double-blind, placebo-controlled study. Sotalol Multicenter Study Group

Sotalol is an antiarrhythmic agent with combined beta-blocking and class III antiarrhythmic properties. This study was designed to assess the safety and efficacy of sotalol in terminating supraventricular tachycardia (SVT), atrial fibrillation (AFib), and atrial flutter (AFl). Ninety-three patients with spontaneous or induced SVT (n = 45) or AF (AFib or AFl; n = 48) with a ventricular rate of > or = 120 beats/min were studied. In the first phase, the double-blind phase, patients were randomly assigned to receive placebo or intravenous (i.v.) sotalol, 1.0 or 1.5 mg/kg. If SVT or AF did not convert to sinus rhythm or if the ventricular rate did not slow to < 100 beats/min within 30 minutes, patients then entered the second phase, the open-label phase, which also lasted 30 minutes, and were given 1.5 mg/kg iv sotalol. In the SVT group, during the double-blind phase conversion to sinus rhythm occurred in 2 (14%) of 14 of patients who received placebo, 10 (67%) of 15 who received sotalol, 1.0 mg/kg (p < 0.05 vs placebo), and 10 (67%) of 15 who received 1.5 mg/kg sotalol (p < 0.05 vs placebo); during the open-label phase, 1.5 mg/kg i.v. sotalol converted 7 (41%) of 17 of patients. In the AF group, during the double-blind phase conversion to sinus rhythm occurred in 2 (14%) of 14 of patients who received placebo, 2 (11%) of 18 who received 1.0 mg/kg sotalol (p not significant [NS] vs placebo), and 2 (13%) of 16 who received 1.5 mg/kg sotalol (p = NS vs placebo); in these groups, a > 20% reduction of ventricular rate without conversion to sinus rhythm occurred in 0 (0%) of 14, 13 (72%) of 18 (p < 0.05 vs placebo), and 12 (75%) of 16 of patients (p < 0.05 vs placebo), respectively; during the open-label phase, 1.5 mg/kg i.v. sotalol converted 7 (30%) of 23 of patients. The most common adverse events were hypotension and dyspnea. During the double-blind phase they occurred in 10% of patients who received placebo, 9% of those who received 1.0 mg/kg i.v. sotalol (p = NS vs placebo), and 10% of those who received 1.5 mg/kg i.v. sotalol (p = NS vs placebo). Most of these events were mild to moderate, but all were transient and clinically manageable.(ABSTRACT TRUNCATED AT 400 WORDS)

Sotalol: from "just another beta blocker" to "the prototype of class III antidysrhythmic compound"

Sotalol is a beta-blocking drug devoid of membrane stabilizing properties, as well as intrinsic sympathomimetic actions, or cardioselectivity. In addition, sotalol prolongs atrial and ventricular repolarization (Class III antiarrhythmic activity). It appears to have less myocardial depressant effect than other beta-blocking agents. Given orally, bioavailability of the drug reaches 100%. Sotalol's plasma half-life is 15 hours (range 7-18) and is dependent only on renal function. In clinical practice, it has been found effective in the suppression of nearly all supraventricular and ventricular dysrhythmias except those related to prolonged ventricular repolarization. Most common adverse effects are dyspnea, bradycardia, and fatigue, which results in drug termination in 16% of the cases. Torsades de pointes usually associated with bradycardia and drug induced QTc prolongation has been reported in 1.9%-3.5% of the patients receiving sotalol. This complication may be reduced by limiting the dose (< 640 mg/day) especially in patients with impaired renal function. In addition hypokalemia must be avoided. To sum up, the combination of Class II and Class III effects may carry additional benefits. However, further studies are required to test such hypotheses.

Sotalol controlled-release systems for arrhythmias: in vitro characterization, in vivo drug disposition, and electrophysiologic effects

An array of controlled-release formulations of sotalol were investigated for epicardial drug delivery in short-term and chronic long-term treatment models with dogs. A nondegradable matrix formulation of sotalol made with polyurethane was studied by use of short-term treatment model with dogs, and the electrophysiologic effects were compared with those resulting from an intravenous dose of 2 mg/kg of body weight. Epicardial sotalol-polyurethane matrices were also used in 7-day canine implant studies. A sotalol-silicone rubber matrix was used in 60-day epicardial canine implant studies. A biodegradable poly(dl-lactide-co-glycolide) (PLGA) microsphere formulation of sotalol was also studied as a pericardial injection in another series involving 30-day dog experiments. The short-term treatment electrophysiologic effects observed with the epicardial (left ventricular) implantation of a sotalol-polyurethane matrix formulation were comparable to those observed with intravenous sotalol. However, the total dose delivered by the matrix over a 2-h experimental period was 25 times smaller than the intravenous dose (0.077 versus 2 mg/kg). Furthermore, coronary venous sotalol levels after sotalol-polyurethane matrix implantation were in the therapeutic range (1812.4 +/- 415.1 ng/mL), whereas simultaneous peripheral venous levels were more than 1 order of magnitude lower (149.8 +/- 14.1 ng/mL). An intravenous bolus administration of sotalol (2 mg/kg) resulted in coronary venous levels (1537.1 +/- 44.6 ng/mL) that were very close to simultaneous peripheral venous levels (1428.6 +/- 63.9 ng/mL).(ABSTRACT TRUNCATED AT 250 WORDS)

Sotalol: a breakthrough antiarrhythmic?

OBJECTIVE

To review the pharmacology, pharmacokinetic, dosing, adverse effects, and therapeutic uses of sotalol.

DATA IDENTIFICATION

Articles were identified with an English-language literature computer search via Knowledge Finder, using the term sotalol, and with an extensive search of bibliographies of identified articles.

STUDY SELECTION

Relevant or representative animal studies, human trials, and case reports were selected for evaluation.

DATA EXTRACTION

The literature was assessed for quality, methodology, and outcome information.

DATA SYNTHESIS

Sotalol is a racemic compound with Class II (beta-blocking properties) and Class III (prolonged action potential) antiarrhythmic activity. It has been suggested that the plasma concentration associated with QTc prolongation (a measure of the Class III action) is much greater than that associated with beta-blockade. Therefore, sotalol is categorized as a Class III antiarrhythmic agent. The 1-isomer is responsible for the beta-blocking activity, whereas both isomers have Class III properties. After oral dosing in fasting patients with normal renal function, sotalol is > 90 percent absorbed, achieves peak serum concentrations in 2-4 h, is excreted unchanged 80-90 percent in the urine, has a volume of distribution of 1-2 L/kg, and has an elimination half-life of about 12 h. Sotalol is effective in patients with life-threatening ventricular arrhythmias that have been refractory to other conventional antiarrhythmic drugs. In general, sotalol appears to be well tolerated, with many of its adverse effects caused by beta-blocking activity. As with other antiarrhythmic agents, the possibility of proarrhythmia (frequently torsade de pointes) exists.

CONCLUSIONS

Racemic sotalol is an effective Class III antiarrhythmic agent approved by the Food and Drug Administration for the treatment of documented life-threatening ventricular arrhythmias. Investigations continue with racemic sotalol in the management of supraventricular arrhythmias. Trials with the d-isomer are also ongoing.

Sotalol. An updated review of its pharmacological properties and therapeutic use in cardiac arrhythmias

Sotalol is a nonselective beta-adrenoceptor antagonist which prolongs cardiac repolarisation independently of its antiadrenergic action (class III antiarrhythmic properties). The antiarrhythmic action of sotalol appears to arise predominantly from its class III properties, and the drug exhibits a broader antiarrhythmic profile than the conventional beta-blockers. Sotalol is effective in controlling paroxysmal supraventricular tachycardias and the ventricular response to atrial fibrillation/flutter in Wolff-Parkinson-White syndrome, in maintaining sinus rhythm after cardioversion of atrial fibrillation/flutter, and in preventing initiation of supraventricular tachyarrhythmias following coronary artery bypass surgery. Sotalol shows promise in the control of nonmalignant and life-threatening ventricular arrhythmias, particularly those associated with ischaemic heart disease. It is effective in suppressing complex forms of ventricular ectopy, displaying superior antiectopic activity to propranolol and metoprolol. The acute efficacy of sotalol in preventing reinduction of sustained ventricular tachyarrhythmias and suppressing spontaneous episodes of these arrhythmias on Holter monitoring is translated into long term prophylactic efficacy against arrhythmia recurrence in approximately 55 to 85% of patients with refractory life-threatening ventricular arrhythmias. In addition, sotalol offers the advantage over the class I agents of reducing cardiac and all-cause mortality in the high risk population with life-threatening ventricular arrhythmias. The adverse effects of sotalol are primarily related to its beta-blocking activity and its class III property of prolonging cardiac repolarisation. Sotalol is devoid of overt cardiodepressant activity in patients with mild or moderate left ventricular dysfunction. The overall arrhythmogenic potential is moderately low, but torsade de pointes may develop in conjunction with excessive prolongation of the QT interval due to bradycardia, hypokalaemia or high plasma concentrations of the drug. In summary, sotalol displays a broad spectrum of antiarrhythmic activity, is haemodynamically well tolerated, and confers a relatively low proarrhythmic risk. It is likely to prove particularly appropriate in the treatment and prophylaxis of life-threatening ventricular tachyarrhythmias.

Sotalol: a novel beta-blocker with class III anti-arrhythmic activity

Initially synthesized in 1960, sotalol is a novel beta-adrenoreceptor blocking agent that also possesses class III anti-arrhythmic properties. The drug's ability to lengthen repolarization and prolong effective refractory periods in all cardiac tissues in addition to its beta-blocking effects make sotalol an attractive agent for use in a variety of supraventricular and ventricular arrhythmias.

Sotalol

Sotalol causes noncardioselective beta-adrenergic antagonism and prolongation of repolarization of cardiac tissues (Class III electrophysiologic action). This dual pharmacologic profile confers unprecedented antiarrhythmic properties to the drug. Sotalol is highly bioavailable when administered orally in the fasting state and is mostly cleared unchanged in the urine with an apparent half-life of elimination of 15 to 17 hours. It has been found effective in the suppression of nearly all cardiac arrhythmias, with the exception of those precipitated by prolongation of ventricular repolarization. Its safety and efficacy relative to other antiarrhythmic drugs need to be examined more fully in randomized controlled trials of unselected patients. The adverse effects potentially associated with the use of sotalol are those commonly observed with beta-adrenergic blockade, as well as those resulting from excessive prolongation of the QT interval. The occurrence of torsade de pointes during treatment with sotalol may be minimized by limiting doses to no more than 640 mg/day and by strictly avoiding the development of hypokalemia.