[Sotalol and quinidine/verapamil (Cordichin) in chronic atrial fibrillation--conversion and 12-month follow-up--a randomized comparison]. Efficacy and proarrhythmic hazards of pharmacologic cardioversion of atrial fibrillation: prospective comparison of sotalol versus quinidine. Maintenance of sinus rhythm in patients with atrial fibrillation: an AFFIRM substudy of the first antiarrhythmic drug. The efficacy of quinidine and disopyramide in the maintenance of sinus rhythm after electroconversion from atrial fibrillation. A double-blind study comparing quinidine, disopyramide and placebo. Maintenance of sinus rhythm after electrical cardioversion of persistent atrial fibrillation; sotalol vs bisoprolol. Efficacy and safety of sotalol versus quinidine for the maintenance of sinus rhythm after conversion of atrial fibrillation. SOCESP Investigators. The Cardiology Society of São Paulo. Use of metoprolol CR/XL to maintain sinus rhythm after conversion from persistent atrial fibrillation: a randomized, double-blind, placebo-controlled study. Maintenance of sinus rhythm after DC reversion of atrial fibrilllation. A double-blind controlled trial of long-acting quinidine bisulphate. Propafenone versus sotalol for suppression of recurrent symptomatic atrial fibrillation.
Atrial fibrillation is one of the most common arrhythmias, leading at least in a subset of patients to severe symptoms (palpitations, weakness, syncope), and to hemodynamic impairment especially in the clinical setting of left ventricular dysfunction. Thus, in many cases restauration of sinus rhythm is indicated because of the negative effects of reduced cardiac output. Quinidine has been the first line drug for many years and has been proven to be highly effective especially when combined with Verapamil. But there is growing concern about using quinidine and other class I-anti-arrhythmic agents because of some hints in clinical trials for increased longterm mortality on these drugs. This study was undertaken to test the efficacy of Sotalol, a beta-blocker with additional strong class-III antiarrhythmic action, compared to a fixed combination of Quinidine and Verapamil for conversion of chronic atrial fibrillation and maintenance of sinus rhythm after medical or electrical cardioversion. To avoid early proarrhythmic effects, potassium values in the range of "high"-normal values (> 4.3 mval/L) were tried to be obtained. 82 patients were randomly assigned to receive either Sotalol or Quinidine/Verapamil. There was no difference between the groups as far as the underlying heart disease, duration of atrial fibrillation (mean 219 days) and other clinical features including echocardiographic parameters were concerned. The dose of the drug was weight-related individually adjusted, and the drug was continued thereafter. If sinus rhythm could not be established at that time, electric cardioversion was performed and the drug was continued in lower dosage thereafter.(ABSTRACT TRUNCATED AT 250 WORDS) This study compared the efficacy and safety of sotalol and quinidine for conversion and prevention of recurrent atrial fibrillation.
                Atrial fibrillation is the most common arrhythmia. Pharmacologic therapy has been advocated for both immediate restoration of sinus rhythm and prevention of recurrent atrial fibrillation. Quinidine is the therapeutic mainstay for both purposes, but its safety has recently been questioned. Although sotalol has been used successfully to maintain sinus rhythm after direct current cardioversion, its efficacy in pharmacologically reverting atrial fibrillation has not been examined.
                Fifty consecutive patients with persistent atrial fibrillation were randomized to receive quinidine or sotalol for up to 7 days to restore sinus rhythm. Patients were followed up for 6 months.
                Quinidine was more effective than sotalol in terminating atrial fibrillation (60% vs. 20%, p = 0.009). When nonresponders to drug therapy underwent subsequent direct current cardioversion, total conversion rates in the quinidine and sotalol groups were comparable (88% vs. 68%, p = 0.17), as was the efficacy of the two drugs in preventing recurrent atrial fibrillation. Side effects necessitating drug discontinuation were more often observed with quinidine. No patient receiving sotalol but four patients receiving quinidine had drug-associated arrhythmia (torsade de pointes in three patients, sustained ventricular tachycardia in one patient). Precordial QT dispersion determined on the surface electrocardiogram (ECG) increased with quinidine (mean +/- SD 34 +/- 9 vs. 44 +/- 16 ms, p = 0.02), indicating enhanced inhomogeneity in ventricular repolarization. There was no change in QT dispersion in patients receiving sotalol (36 +/- 18 vs. 40 +/- 17 ms, p = 0.44).
                Quinidine is more effective than sotalol in terminating atrial fibrillation but is associated with more side effects. The proarrhythmic risk may be related to quinidine's propensity to increase disparity in ventricular repolarization. This risk warrants careful ECG monitoring during the 1st 4 to 7 days of therapy. Because most proarrhythmic effects occurred shortly after restoration of sinus rhythm, observation should continue > or = 2 to 3 days after sinus rhythm is reestablished. This study evaluated the efficacy of antiarrhythmic drugs for the treatment of atrial fibrillation (AF).
                The most effective and safest antiarrhythmic drug for the treatment of AF is unknown.
                The Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study compared two treatment strategies--rate control and rhythm control--in patients with AF and risk factors for stroke or death. This substudy, performed in patients randomized to rhythm control, compared different antiarrhythmic drugs by randomly assigning the first drug treatment to: 1) amiodarone, 2) sotalol, or 3) a class I drug. The primary end point was the proportion of patients alive, in sinus rhythm, with no additional cardioversions and still taking the assigned drug at one year. Comparisons were made between patients eligible for each of three drug pairs.
                At one year, in 222 patients randomized between amiodarone and class I agents, 62% were successfully treated with amiodarone, compared with 23% taking class I agents (p < 0.001). In 256 patients randomized between amiodarone and sotalol, 60% versus 38% were successfully treated, respectively (p = 0.002). In 183 patients randomized between sotalol and class I agents, 34% versus 23% were successfully treated, respectively (p = 0.488), although this portion of the substudy was stopped early when amiodarone was shown to be better than class I agents. Sinus rhythm was achieved in nearly 80% of patients at one-year follow-up with serial therapy. Adverse effects were common.
                Amiodarone was more effective at one year than either sotalol or class I agents for the strategy of maintenance of sinus rhythm without cardioversion. In order to compare the relative efficacy of quinidine, disopyramide and a placebo in the maintenance of sinus rhythm after cardioversion from atrial fibrillation and in order to examine the incidence of side-effects, 82 patients with continuous atrial fibrillation (duration more than 1 month but less than 3 years) were randomized in a double-blind fashion to receive quinidine, disopyramide or placebo. Six months after cardioversion there was no significant difference between any of the three groups as regards the number of patients remaining in sinus rhythm. The greater distortion of the atrial architecture which occurs in patients with rheumatic mitral valve disease may explain the failure of these anti-arrhythmic agents to prolong the duration of sinus rhythm in this study, in which patients with valvular heart disease comprised 76% of the total group. The purpose of the study was to compare the efficacy and safety of sotalol and bisoprolol in the maintenance of sinus rhythm after electrical cardioversion of atrial fibrillation.
                Patients (n=128) were randomized to sotalol (80 mg b.i.d.) or bisoprolol (5 mg x day(-1)). Patients with contraindications to beta-blockers, class III antiarrhythmic drugs or prior treatment with use of study medication for prevention of atrial fibrillation were excluded. Follow-up clinical evaluation was performed 1 day and 1 month after cardioversion and thereafter at 3-month intervals.
                There were no group differences in baseline clinical characteristics. After a follow-up of 12 months, 59% of all patients were still in sinus rhythm. The fraction remaining in sinus rhythm was calculated for the two groups by Kaplan--Meier analysis. During follow-up, 41% of patients on sotalol and 42% on bisoprolol developed atrial fibrillation (ns). In two patients (3.1%) on sotalol, life-threatening proarrhythmias (torsade de pointes tachycardias) occurred, whereas none were found in the bisoprolol group. Symptomatic bradycardias occurred in two patients on sotalol and three on bisoprolol.
                This study demonstrates that sotalol (160 mg x day(-1)) and bisoprolol (5 mg x day(-1)) are equally effective in maintaining sinus rhythm. Because of the side effects of sotalol, bisoprolol seems to be advantageous for maintenance of sinus rhythm after cardioversion of atrial fibrillation.
                Copyright 2001 The European Society of Cardiology. To compare the efficacy and safety of sotalol and quinidine after conversion of atrial fibrillation (AF) of <6 months, a prospective multicenter trial enrolled 121 patients who were randomized to receive dl-sotalol (160 to 320 mg/day, 58 patients) or quinidine sulfate (600 to 800 mg/day, 63 patients). Patients with left ventricular ejection fraction of <0.40 or left atrial diameter >5.2 cm were excluded. After 6 months of follow-up, using the Kaplan-Meier method, the probabilities of success were comparable between sotalol (74%) and quinidine (68%), but recurrences occurred later with sotalol than with quinidine (69 vs 10 days, p <0.05). Four patients developed proarrhythmic events, 3 (5%) with sotalol and 1 (2%) with quinidine, which were all associated with diuretic therapy. In patients converted from recent-onset AF (< or = 72 hours), sotalol was more effective than quinidine (93% vs 64%, p = 0.01), whereas in chronic AF (> 72 hours), quinidine was more effective than sotalol (68% vs 33%, p <0.05). During recurrences, the ventricular rate was significantly reduced in patients taking sotalol (98 to 82 beats/min, p <0.05). Independent predictors of therapeutic success were recent-onset AF in the sotalol group (p <0.001) and absence of hypertension in the quinidine group (p <0.05). In conclusion, sotalol and quinidine have comparable efficacy and safety for the maintenance of sinus rhythm in the overall group. In recent-onset AF, sotalol was more effective, whereas in chronic AF, quinidine had a better result. Recurrences occurred later with sotalol when compared with quinidine. Because of proarrhythmia, these drugs should be used judiciously in patients on diuretic therapy. The primary objective of the present study was to assess the efficacy of metoprolol CR/XL to reduce the risk of relapse after cardioversion of persistent atrial fibrillation to sinus rhythm.
                Indirect data from studies with d,l sotalol provide evidence that the beta-blocking effects of the compound are important in maintaining sinus rhythm after cardioversion of atrial fibrillation.
                After successful conversion to sinus rhythm, 394 patients with a history of persistent atrial fibrillation were randomly assigned to treatment with metoprolol CR/XL or placebo. The two treatment groups were similar with respect to all pretreatment characteristics. Patients were seen on an outpatient basis for recording of resting electrocardiogram (ECG) after one week, one, three and six months of follow-up or whenever they felt that they had a relapse into atrial fibrillation or experienced an adverse event.
                In the metoprolol CR/XL group, 96 patients (48.7%) had a relapse into atrial fibrillation compared with 118 patients (59.9%) in the placebo group (p = 0.005). Heart rate in patients after a relapse into atrial fibrillation was significantly lower in the metoprolol group (98 +/- 23 beats/min) than in the placebo group (107 +/- 27 beats/min). The rate of adverse events reported was similar in both groups when the difference in follow-up time was taken into account.
                The results of this double-blind, placebo-controlled study in patients after cardioversion of persistent atrial fibrillation showed that metoprolol CR/XL was effective in preventing relapse into atrial fibrillation or flutter. Ninety-two patients were entered in a double-blind controlled trial of long-acting quinidine bisulphate for the maintenance of sinus rhythm following DC reversion of atrial fibrillation. By random selection two statistically comparable groups of patients were obtained, a control group being given a placebo and a treated group quinidine bisulphate 1.5 g. per day in two 12-hourly doses. Thirty-seven patients were followed up in the control group and twenty-eight patients in the treated group. The maintenance of sinus rhythm in the treated group was significantly longer than in the control group, especially during the first three months. The mean serum quinidine level in the treated group was 2.2+/-0.3 (SEM) mg. per litre. There was one death among the patients treated with quinidine, which may have been due to quinidine toxicity caused by a high serum quinidine level. Because conventional antiarrhythmic therapy is often ineffective in maintaining sinus rhythm or is associated with adverse side effects in patients with atrial fibrillation (AF), there is a clinical need to test newer agents. One hundred patients with AF who had unsuccessful therapy with 1.9 +/- 1.0 type IA antiarrhythmic agents were randomized to receive either propafenone (n = 50) or sotalol (n = 50). Patients were stratified into 4 groups based on AF pattern (chronic vs paroxysmal) and left atrial size (large [> or = 4.5 cm] vs small [< 4.5]). The proportion of patients remaining in sinus rhythm on each agent was calculated for each group by the Kaplan-Meier method. For patients randomized to propafenone, 46 +/- 8%, 41 +/- 8% and 30 +/- 8% remained in sinus rhythm at 3, 6 and 12 months, respectively, after cardioversion. A similar proportion of patients treated with sotalol remained in sinus rhythm at follow-up (49 +/- 7%, 46 +/- 8% and 37 +/- 8% at 3, 6 and 12 months, respectively; p = NS). The proportion of patients remaining in sinus rhythm on propafenone and sotalol was not dependent on arrhythmia pattern or left atrial dimension. Except for constipation that occurred more frequently in patients treated with propafenone, adverse side effects were equally distributed between the 2 therapies. Two patients receiving sotalol died during follow-up. Propafenone and sotalol, 2 new antiarrhythmic agents, were found to be equally effective in maintaining sinus rhythm in 100 patients with recurrent AF. Response rates were not affected by arrhythmia pattern, left atrial size or unsuccessful prior drug therapy.(ABSTRACT TRUNCATED AT 250 WORDS)
Several class IA, IC and III drugs, as well as class II (beta-blockers), are moderately effective in maintaining sinus rhythm after conversion of atrial fibrillation. However, they increase adverse events, including pro-arrhythmia, and some of them (disopyramide, quinidine and sotalol) may increase mortality. Possible benefits on clinically relevant outcomes (stroke, embolisms, heart failure) remain to be established.