Conversion of recent onset atrial fibrillation to sinus rhythm using a single oral loading dose of propafenone: comparison of two regimens.

A population of 105 patients with recent onset (< 72 h) atrial fibrillation was randomly treated with propafenone as a single oral loading dose of 450 mg (Regimen A) or 600 mg (Regimen B) or with placebo. A 24-h Holter was performed. Criteria of efficacy were conversion to sinus rhythm at 2, 4 and 8 h compared to placebo and also significant reduction of mean ventricular rate in persistent atrial fibrillation. After 2 h, regimen B was more effective than either regimen A (43% vs. 8%; p = 0.001) or placebo (11%; p = 0.004). At 4 h, both the active treatments were more effective than placebo (17% vs. 46% regimen A and 57% vs. regimen B; p < 0.04 and p < 0.001, respectively). Sinus rhythm resumed within 24 h in 71%, 80% and 69% of the patients with regimen A, B and placebo, respectively (p = not significant). The mean ventricular rate reduction after 1 h was 8%, 11% and 4% for regimen A, B and placebo, respectively (p < 0.005 vs. regimen B), and 17%, 25% and 6% respectively (p < 0.001 placebo vs. regimen A and B, p < 0.05 regimen B vs. A) at 2 h. No major adverse effect occurred. Atrial flutter with 1:1 atrioventricular conduction only in one case who received placebo. Propafenone acute oral administration is more effective than placebo in rapidly converting recent-onset atrial fibrillation to sinus rhythm and may be the treatment of choice in this setting limiting hospitalization and contributing to improved quality of life.

Prophylactic mezlocillin-netilmicin combination in permanent transvenous cardiac pacemaker implantation: a single-center, prospective, randomized study.

A prospective, randomized study was carried out in order to assess the efficacy and safety of the mezlocillin-netilmicin combination in the prophylaxis of first permanent transvenous cardiac pacemaker implantation. Five hundred and fifty-two consecutive patients were randomly administered either 2 g mezlocillin and 200 mg netilmicin both as an i.v. bolus before implantation or 2g mezlocillin before and then 6 and 12 hours after surgery and 200 mg netilmicin before and then 12 hours after implantation. No adverse events were seen. Neither pocket nor electrode infections were observed in the 457 subjects still alive (mean follow-up: 29.2 months) or in patients who died after 1 year of follow-up (mean follow-up: 20.1 months) or before this time (mean follow-up: 4.7 months). The serum and pocket concentrations of mezlocillin and netilmicin at the end of surgery were found to be adequate to cover microorganisms that most often cause infections, including methicillin-resistant staphylococci.

Modulation of ventricular rate in permanent atrial fibrillation: randomized, crossover study of the effects of slow-release formulations of gallopamil, diltiazem, or verapamil.

BACKGROUND: The management of permanent atrial fibrillation (PAF) consists primarily of long-term anticoagulation with either aspirin or warfarin to prevent systemic embolization, and modulation of ventricular rate (VR) to improve cardiac function by prolonging the ventricular diastolic filling time. HYPOTHESIS: The effects of slow-release formulations of gallopamil (100 mg b.i.d.), diltiazem (120 mg b.i.d.), or verapamil (120 mg b.i.d.) on VR were evaluated in 18 patients with PAF without organic heart disease. METHODS: In all patients, each treatment was administered randomly, was compared with oral digoxin, and was assessed by 24-h Holter monitoring during daily life and by a 6-min walking test. RESULTS: There were no significant differences in mean and minimum VR recorded during 24-h Holter monitoring among the four treatments. Peak heart rates recorded during the 6-min walking test with digoxin treatment was 167 +/- 12 beats/min. This was significantly reduced by gallopamil (149 +/- 23 beats/min, p = 0.01), diltiazem (142 +/- 24 beats/min, p < 0.001), and verapamil (137 +/- 30 beats/min, p < 0.001). There were no significant differences in peak VR during the walking test among the three calcium antagonists. Pauses of > 3 s were observed in 3 of 18 (17%) patients who received digoxin (max 3.4 s) and in 5 of 18 (28%) patients who received diltiazem (max 3.4 s); p = NS. Periods of bradycardia < 30 beats/min were observed in 5 of 18 (28%) patients during digoxin treatment, and in 3 of 18 (17%) patients during treatment with gallopamil, diltiazem, and verapamil; p = NS. CONCLUSION: Gallopamil, diltiazem, or verapamil are superior to digoxin in controlling VR during mild exercise in patients with PAF without organic heart disease. The reduction of peak VR is obtainable without further slowing of resting VR. However, gallopamil appears to be the least effective calcium blocker at controlling resting and exercise VR; thus, there are no advantages over the other calcium blockers in its use in the clinical setting.

A new system for follow-up patients with permanent pacemakers.

The use of a new computerized system for coordinating technical and clinical data and especially for filing the parameters found during out-patient checkups enables us to rationally carry out follow-up of approximately 900 patients with pacemakers in our electrostimulation laboratory without wasting time or data. The system is composed of a personal Olivetti M240 computer, with a 20 Bbyte and 640 Kram hard disk, an analog-digital interface and a personalized data base for coordinating and filing the parameters found. The type of pacemaker implanted (monocameral, dual chamber or rate responsive) is of no consequence to the system that is based on the acquisition of the surface electrocardiogram. A comparison of the filed data on printouts or graphs allows us to note every type of misfunction or anomaly in the stimulation system in real time.

Pregnancy with an ICD and a documented ICD discharge.

We report a successful pregnancy in a patient affected by idiopathic ventricular fibrillation 3 years after insertion of an ICD, with a documented defibrillator discharge.

External cardioversion of atrial fibrillation: role of paddle position on technical efficacy and energy requirements.

AIM: To define the effect of defibrillator paddle position on technical success and dc shock energy requirements of external cardioversion of atrial fibrillation. METHODS: 301 patients (mean (SD) age 62 (11) years) with stable atrial fibrillation were randomly assigned to elective external cardioversion using anterolateral paddle position (ventricular apex-right infraclavicular area; group AL (151 patients)) or anteroposterior paddle position (sternal body-angle of the left scapula; group AP (150 patients)). A step up protocol was used, delivering a 3 J/kg body weight dc shock, then a 4 J/kg shock (maximum 360 J), and finally a second 4 J/kg shock using the alternative paddle location. RESULTS: The two groups were comparable for the all clinical variables evaluated. The cumulative percentage of patients successfully converted to sinus rhythm was 58% in group AL and 67% in group AP with low energy dc shock (NS); this rose to 76% in group AL and to 87% in group AP with high energy dc shock (p = 0.013). Thirty seven patients in group AL and 19 in group AP experienced dc shock with the alternative paddle position; atrial fibrillation persisted in 10/37 in group AL and in 10/19 in group AP. Mean dc shock energy requirements were lower for group AP patients than for group AL patients, at 383 (235) v 451 (287) J, p = 0.025. Arrhythmia duration was the only factor that affected the technical success of external cardioversion (successful: 281 patients, 80 (109) days; unsuccessful: 20 patients, 193 (229) days; p < 0.0001). The success rate was lower if atrial fibrillation persisted for > 6 months: 29 of 37 (78%) v 252 of 264 (95%); p = 0.0001. CONCLUSIONS: An anteroposterior defibrillator paddle position is superior to an anterolateral location with regard to technical success in external cardioversion of stable atrial fibrillation, and permits lower dc shock energy requirements. Arrhythmia duration is the only clinical variable that can limit the restoration of sinus rhythm.

Regular ventricular rhythms before conversion of recent onset atrial fibrillation to sinus rhythm.

The incidence of fast atrial tachycardias with regular ventricular rhythm was assessed in a population of 243 patients with recent onset (< 72 hours) atrial fibrillation (AF), without heart failure, randomly treated with single loading oral dose of propafenone (600 mg), flecainide (300 mg), digoxin (1 mg), or placebo for acute conversion to sinus rhythm (SR). Fast atrial arrhythmias developed in 14 (6%) patients: 6/92 treated with propafenone, 3/34 treated with flecainide, 1/25 treated with digoxin, and 4/92 who received placebo (P = NS). Heart rate > 175 beats/min with 1:1 AV conduction ensued in 4 cases: 2 treated with flecainide and 2 treated with placebo; in the other cases 2:1 AV conduction was observed. Widening of QRS during regular tachycardia was observed in 4 patients; 3 who received propafenone and 1 who received flecainide. Conversion to SR within 4 hours was achieved in 55/92 (60%) patients treated with propafenone, 20/34 (59%) patients treated with flecainide, 7/25 (28%) patients treated with digoxin, and 19/92 (20%) treated with placebo (P < 0.001 propafenone vs placebo and flecainide vs placebo; P < 0.05 propafenone vs digoxin and flecainide vs digoxin). Periods of regular tachycardia are expected in recent onset AF and may not necessarily represent a proarrhythmic effect of Class 1C drugs, rather than mark the transition from AF to SR. Class 1C agents are probably responsible for widening of the QRS complex seen during these tachycardias. Propafenone and flecainide appear equally effective in converting recent onset AF.

Oral propafenone to convert recent-onset atrial fibrillation in patients with and without underlying heart disease. A randomized, controlled trial.

BACKGROUND: The effectiveness of oral propafenone in converting recent-onset atrial fibrillation to sinus rhythm has been established by controlled trials. However, it is not clear whether the effectiveness of propafenone is affected by the presence or absence of underlying heart disease. OBJECTIVES: To investigate the safety and effectiveness of oral propafenone and the role of underlying heart disease. DESIGN: Randomized, single-blind, controlled study. SETTING: 3 teaching hospitals. PATIENTS: 240 hospitalized patients with recent-onset atrial fibrillation. INTERVENTION: Propafenone (one 500-mg oral dose) or placebo. MEASUREMENTS: Conversion rates at 3 and 8 hours. RESULTS: Propafenone was more effective than placebo for converting atrial fibrillation to sinus rhythm at 3 hours: Fifty-four of 119 patients (45%) receiving propafenone and 22 of 121 patients (18%) receiving placebo had conversion (P < 0.001). It was also more effective at 8 hours: Ninety-one of 119 patients (76%) receiving propafenone and 45 of 121 patients (37%) receiving placebo had conversion (P < 0.001). Subgroup analysis showed that among patients without heart disease, 78% of those receiving propafenone and 56% of those receiving placebo converted to sinus rhythm within 8 hours (P = 0.02). In those with hypertension, the rate was 70% for those receiving propafenone and 27% for those receiving placebo (P < 0.001); in patients with structural heart disease, the rate was 81% for those receiving propafenone and 17% for those receiving placebo (P < 0.001). CONCLUSIONS: Oral loading of propafenone was more effective than placebo for conversion to sinus rhythm within 8 hours and had a favorable safety profile. The rate of spontaneous conversion to sinus rhythm was higher in patients without structural heart disease; this finding has important implications for the assessment of drug effectiveness in recent-onset atrial fibrillation.

Conversion of recent onset atrial fibrillation with single loading oral dose of propafenone: is in-hospital admission absolutely necessary?

A population of 283 patients with recent onset (< 72 hours) AF, without heart failure, who received a single 450- or 600-mg oral dose of propafenone, or digoxin 1 mg, or placebo for conversion to sinus rhythm (SR), was studied to determine whether a routine admission to the hospital for drug administration is justified. Previous bradyarrhythmias or sick sinus syndrome (SSS), and concomitant use of antiarrhythmic drugs were exclusion criteria. None of the 283 patients studied experienced VT or VF and none of them needed implantation of a temporary pacemaker. Periods of atrial tachyarrhythmias with regularization of atrial waves and 1:1 AV conduction were observed in only two cases, both receiving placebo. No predictor of proarrhythmia was found among the clinical variables considered (age, etiology, arrhythmia duration, atrial dimension, and blood potassium). No serious hemodynamic adverse effects were noted in either group. The rates of conversion to SR after 4 hours were: 80 (57%) of 141 patients who received propafenone and 35 (25%) of 142 patients who received digoxin or placebo (P < 0.001). Acute oral treatment with propafenone is simple and effective for the conversion of recent onset AF to SR in patients without clinical signs of heart failure. The routine admission of these patients to the hospital is not necessary. Home-based administration of oral propafenone to a selected group of patients could significantly increase the cost effectiveness of this treatment.

Oral loading with propafenone: a placebo-controlled study in elderly and nonelderly patients with recent onset atrial fibrillation.

UNLABELLED: The efficacy and safety of propafenone as an oral loading dose (600-mg single oral dose) in converting recent-onset atrial fibrillation (< or = 7 days duration) to sinus rhythm were evaluated in a single-blind, placebo-controlled study according to patients' age. Overall, 240 hospitalized patients, NYHA Class < or = 2 without signs or symptoms of heart failure were enrolled: among patients aged < or = 60 years, 55 were allocated to propafenone treatment and 59 to placebo, respectively, and among patients aged > 60 years, 64 were allocated to propafenone treatment and 62 to placebo, respectively. RESULTS: In each age group, the likelihood of conversion to sinus rhythm was significantly greater after propafenone compared with placebo at 3 and 8 hours. For patients aged < or = 60 years, corresponding odd ratios were 3.78 (95% CI = 1.80-7.92, P = 0.04) at 3 hours and 4.74 (95% CI = 2.12-10.54, P = 0.02) at 8 hours; for patients aged > 60 years odd ratios were 5.03 (95% CI = 2.08-12.12, P = 0.02) at 3 hours and 6.75 (95% CI = 3.28-73.86, P = 0.01) at 8 hours, respectively. Logistic regression analysis showed that conversion to sinus rhythm within 3 hours was predicted by age < or = 60 years (P = 0.0064) and by propafenone treatment (P < 0.0001), and conversion to sinus rhythm within 8 hours was predicted by age < or = 60 years (P = 0.0467) and by propafenone treatment (P < 0.0001). The occurrence of adverse effects was observed in 14%-16% of propafenone treated patients and in 8% of placebo treated patients without significant differences according to age. In conclusion, in patients with recent-onset atrial fibrillation without signs of heart failure, propafenone as a single oral loading dose is effective. It is also effective in selected elderly subjects with a favorable safety profile. Moreover, spontaneous conversion to sinus rhythm appears to occur less frequently in elderly patients.

Conversion of recent-onset atrial fibrillation to sinus rhythm: effects of different drug protocols.

UNLABELLED: In a population of 417 hospitalized patients, the efficacy and safety of different drug regimens administered to convert atrial fibrillation (AF) of recent onset (< or = 7 days duration) to sinus rhythm were evaluated. All patients were in NYHA Class < or = 2, and free of heart failure. They were randomly allocated to treatment with placebo in 121 patients; i.v. amiodarone, 5 mg/kg bolus, followed by 1.8 g/24 hours in 51 patients; i.v. propafenone, 2 mg/kg bolus, followed by 0.0078 mg/kg/min in 57 patients; p.o. propafenone, 600 mg p.o. in a single dose in 119 patients; and p.o. flecainide, 300 mg p.o. in a single dose in 69 patients. All patients were continuously monitored by Holter ECG, and the number of conversions to sinus rhythm was measured at 1, 3, and 8 hours. RESULTS: (1) I.v. propafenone resulted in a higher conversion rate within 1 hour compared with the oral loading regimens of propafenone or flecainide, but the conversion rates at 3 and 8 hours were comparable, approximately 75% at 8 hours; 2) i.v. amiodarone was not different from placebo until 8 hours when it was associated with 57% of conversions; (3) conversion to sinus rhythm at 8 hours was observed in 37% of the placebo treated patients. Serious adverse effects occurred in few patients: two patients treated with flecainide and one treated with i.v. propafenone experienced left ventricular decompensation; one patient treated with placebo and two treated with flecainide had atrial flutter with rapid ventricular response. In conclusion, single-dose, oral loading with propafenone or flecainide are acceptable alternatives to conventional drug regimens in selected hospitalized patients. In addition, the measure of a placebo effect is mandatory in studies of recent-onset AF.

Randomized, crossover, controlled comparison of oral loading versus intravenous infusion of propafenone in recent-onset atrial fibrillation.

A population of 123 patients with recent-onset (< 72 hours) atrial fibrillation (AF) without heart failure was randomly treated with propafenone (PFN) intravenously (i.v.) (2 mg/kg bolus followed by 0.0078 mg/kg/min infusion) or in a single oral dose (o.s.) (600 mg), or with placebo (PLA) (phase 1). If AF persisted 8 hours later, patients on active drugs received the alternative formulation (crossover), and patients receiving PLA remained on PLA (phase 2). A 24-hour Holter monitoring was performed and conversion to sinus rhythm (SR) at 1, 4, and 8 hours of each phase was used as the criterion of efficacy. Conversion to SR occurred within 1 hour in 48% of patients with i.v.-PFN, 15% with o.s.-PFN, and in 17% with PLA (both P < 0.05 vs i.v.-PFN). Oral PFN was superior to PLA at 4 hours (71% vs 33%, P = 0.001) and 8 hours (78% vs 48%, P < 0.01), and 1 at 8 hours also superior to i.v.-PFN (53%, P < 0.03). The mean conversion time within 4 hours was shorter with i.v.-PFN (25 +/- 15') than with o.s.-PFN (167 +/- 166', P < 0.001) or with PLA (156 +/- 107', P < 0.001). The rates of conversion to SR with i.v.-PFN after o.s.-PFN failure were comparable to PLA at any observation time, whereas nonresponders to i.v.-PFN who received o.s.-PFN had significantly higher conversion rates than with placebo at both 4 hours (65% vs 19%) and 8 hours (76% vs 24%; both P < 0.045). Neither serious adverse effects nor episodes of regular tachycardia with 1:1 AV conduction were noted. PFN administered intravenously or in a single oral loading dose was safe and efficacious in converting recent-onset AF to SR. The rates of conversion were different with different routes of administration: i.v.-PFN was superior to o.s.-PFN over a short observation period, while the overall efficacy of o.s.-PFN was superior at 8 hours.