Propafenone (Rythmonorm) was administered intravenously at a dose of 5mg/kg/3h to treat an atrial fibrillation case. Synal rhythm was restored in 2.30 hours with a QRS complex enlargement. 3 hours later on, a blood pressure drop as well as a cerebral and myocardial ischemia lasting 2 days were noted and were managed effectively with isoproterenol and dopamine. These drugs administered orally in divided doses up to 450 mg/day can put an end to the atrial fibrillation paroxysm while the maintenance dose of 450mg/day in fractional doses can prevent atrial fibrillation recurrence
Anti-Arrhythmia Agents ; Propafenone ; Overdose ; Accidents

BACKGROUND/AIMS: Long-term antiarrhythmic drug therapy remains the principal approach for suppressing atrial fibrillation (AF) and maintaining sinus rhythm. In this study, we examined the differing electrophysiological effects of various antiarrhythmic drugs on the cardiac chamber and atrial selectivity in patients with AF. METHODS: We analyzed 134 patients (60.4 +/- 12.5 years, M:F = 1.14:1) who were administered a single antiarrhythmic agent for AF over 6 months: amiodarone (group A), flecainide (group F), or propafenone (group P). The P wave, QRS complex duration and dispersion, and QT interval and its dispersion were evaluated using a standard 12-lead electrocardiogram. RESULTS: There was no significant difference in age, gender ratio, or associated diseases among the three groups. In group A, Pmax, Pmin, P dispersion, QRSmax, QRSmin, and QRS dispersion were shorter than in groups F and P, whereas Pmax/QRSmax was the highest in group A (A = 1.2, F = 0.9, P = 1.0; p < 0.01). QTcmax and QTcmin were longer in group A, whereas QTc dispersion and the QT peak to end (A = 13.3 +/- 11.2, F = 30.7 +/- 24.9, P = 31.8 +/- 21.6; p < 0.01) were shorter in group A than in the other groups. CONCLUSIONS: Amiodarone had a weaker, but more selective, inhibitory effect on intra-atrial conduction, and inhibited ventricular repolarization more effectively and homogenously than flecainide or propafenone. These differing electrophysiological effects may contribute to the superior effectiveness and safety of amiodarone over flecainide or propafenone.
Amiodarone ; Anti-Arrhythmia Agents ; Atrial Fibrillation ; Electrophysiology ; Flecainide ; Humans ; Propafenone

In this study, we demonstrated the inhibitory effect of the Class Ic antiarrhythmic agent propafenone on voltage-dependent K⁺ (Kv) channels using freshly isolated coronary artery smooth muscle cells from rabbits. The Kv current amplitude was progressively inhibited by propafenone in a dose-dependent manner, with an apparent IC₅₀ value of 5.04±1.05 µM and a Hill coefficient of 0.78±0.06. The application of propafenone had no significant effect on the steady-state activation and inactivation curves, indicating that propafenone did not affect the voltage-sensitivity of Kv channels. The application of train pulses at frequencies of 1 or 2 Hz progressively increased the propafenone-induced inhibition of the Kv current. Furthermore, the inactivation recovery time constant was increased after the application of propafenone, suggesting that the inhibitory action of propafenone on Kv current is partially use-dependent. Pretreatment with Kv1.5, Kv2.1 or Kv7 inhibitor did not change the inhibitory effect of propafenone on the Kv current. Together, these results suggest that propafenone inhibits the vascular Kv channels in a dose- and use-dependent manner, regardless of Na⁺ channel inhibition.
Coronary Vessels ; Muscle, Smooth* ; Myocytes, Smooth Muscle* ; Propafenone* ; Rabbits

Concealed bypass tract (CBT) results from incomplete development of the atrioventricular (AV) annulus. CBT conducts only in a retrograde direction, and therefore does not cause pre-excitation on standard electrocardiograms. The most common tachycardia associated with CBT is an orthodromic atrioventricular reentrant tachycardia (AVRT): a pathway involving anterograde circuitry through the AV node and His Purkinje system and retrograde conduction over the accessory pathway. Orthodromic AVRT accounts for approximately 90%-95% cases of AVRT. Most incidences of CBT occur at the left free wall. Vagal maneuvers and/or intravenous (IV) adenosine are recommended for first line acute management of AVRT. However, pharmacological therapy with IV diltiazem, verapamil, or beta blockers can also be effective for acute treatment for orthodromic AVRT in patients who do not show pre-excitation on their resting ECG during sinus rhythm. The first-line ongoing therapy for AVRT is catheter ablation of CBT; when catheter ablation is not indicated or preferred, oral beta blockers, diltiazem, verapamil, flecainide, propafenone, or amiodarone are recommended.
Adenosine ; Amiodarone ; Atrioventricular Node ; Catheter Ablation ; Diltiazem ; Electrocardiography ; Flecainide ; Humans ; Incidence ; Propafenone ; Tachycardia ; Tachycardia, Supraventricular* ; Verapamil

BACKGROUND: Propafenone is a new class IC antiarrhythmic drug that has been found to be effective in both supraventricular and ventricular tachyarrhythmias. We studied the electrophysiologic and long-term effects of oral propafenone in the patients with paroxysmal supraventricular tachycardia(PSVT). METHODS: The electrophysiologic study was done in 15 patients with PSVT to assess the short-term efficacy of propafenone 450mg daily. For 10 patients with short-term efficacy, follow up study was done to assess the long-term efficacy of propafenone 450mg daily. RESULTS: The electrophysiologic mechanisms of PSVT were AV nodal reentry in 6 patients and AV reentry in 9 patients. During the electrophysiologic study, propafenone prolonged AH, HV and PR intervals significantly(p<0.05), but did not change the corrected SNRT, SACT, and the ERP of atrium, ventricle, AV node and accessory pathway(AP) significantly. The anterograde and retrograde 1:1 conduction capacity of AV node and AP seemed to decrease. Complete block of anterograde conduction over the AP was noted in 2 of 3 patients with manifest WPW syndrome and complete block of retrograde conduction was noted over the AV node in 1 patient with AV nodal reentry and over the AP in 1 patient with AV reentry. Propafenone was effective in 3 of 6 patients with AVNRT and 7 of 9 patients with AVRT. During long term administration for 3 to 11 months in 10 patients with short-term efficacy of propafenone, 7 patients did not report any episode of symptomatic tachycardia and 3 patients reported less frequent palpitation. There were no side effects during short-and long-term follow up except 2 patients with mild indigestion. CONCLUSIONS: Propafenone seems to be a safe, well tolerated and effective drug for short and long-term therapy of patients with PSVT, especially of orthodromic AV reentry.
Atrioventricular Node ; Dyspepsia ; Follow-Up Studies ; Humans ; Propafenone* ; Tachycardia ; Tachycardia, Supraventricular* ; Wolff-Parkinson-White Syndrome

BACKGROUND AND OBJECTIVES: Various intravenous (IV) antiarrhythmic drugs in patients with atrial fibrillation (AF) refractory to electrical cardiooversion have been attempted. We assessed the efficacy of IV propafenone in patients with AF who failed to achieve normal sinus rhythm using standard external direct current (DC) cardioversion. SUBJECTS AND METHODS: Of the 77 AF patients who underwent a DC cardioversion, 18, who were refractory for up to a maximal 360 joules of external DC cardioversion, were included in this study. Propafenone was infused for 10 minutes at doses of 2 mg/kg (n=3), 2.5 mg/kg (n=8), and 3 mg/kg (n=7) followed by repeated DC cardioversion. RESULTS: The mean age of the patients receiving propafenone was 55+/-14 years and 21% were women. The mean ejection fraction and the average diameter of the left atrium were 56+/-5% and 42+/-7 mm, respectively. The AF cycle length increased following propafenone infusion form 160+/-23 ms to 278+/-62 ms (p<0.05). The AF converted to a normal sinus rhythm following propafenone infusion in three patients. Thirteen patients were successfully cardioverted following IV propafenone infusion, with a mean accumulated energy of 410+/-216 joules (689+/-373 joules prior to propafenone infusion, p<0.05). Cardioversion failed in 2 patients;therefore, the success rate of the cardioversion in patients who received IV propafenone was 88.9% (16/18). No significant adverse effects were observed. CONCLUSION: IV propafenone can be safely used to enhance the efficacy of cardioversion in patients with AF refractory to transthoracic DC cardioversion.
Anti-Arrhythmia Agents ; Atrial Fibrillation* ; Electric Countershock* ; Female ; Heart Atria ; Humans ; Propafenone*

Wide QRS tachycardia may represent a rare proarrhythmic effect of some antiarrhythmic agents. Class Ic antiarrhythmic agents produce rate- dependent ventricular conduction slowing due to use-dependent sodium channel blockade, causing QRS prolongation in cases with an increased heart rate. The authors describe two cases of atrial flutter with 1:1 atrioventricular conduction exhibiting a wide QRS tachycardia while on therapy using flecainide and propafenone, and the difficulty in interpreting the ECG.
Atrial Fibrillation* ; Atrial Flutter ; Electrocardiography ; Flecainide ; Heart Rate ; Humans ; Propafenone ; Sodium Channels ; Tachycardia*

Wide QRS tachycardia may represent a rare proarrhythmic effect of some antiarrhythmic agents. Class Ic antiarrhythmic agents produce rate- dependent ventricular conduction slowing due to use-dependent sodium channel blockade, causing QRS prolongation in cases with an increased heart rate. The authors describe two cases of atrial flutter with 1:1 atrioventricular conduction exhibiting a wide QRS tachycardia while on therapy using flecainide and propafenone, and the difficulty in interpreting the ECG.
Atrial Fibrillation* ; Atrial Flutter ; Electrocardiography ; Flecainide ; Heart Rate ; Humans ; Propafenone ; Sodium Channels ; Tachycardia*

BACKGROUND: Atrial fibrillation (AF) is one of the most common complications after cardiac surgery. Several therapeutic and preventive strategies have been introduced for postoperative AF, but the treatment and prophylaxis of AF remain controversial. We aimed to compare the efficacy of intravenous amiodarone and oral propafenone in the treatment of AF after coronary artery bypass grafting (CABG). METHODS: This was a randomized controlled trial performed in two hospitals in Shiraz, Iran from 2009 to 2012. We included all patients who underwent elective CABG and developed AF postoperatively. The patients were randomly assigned to receive propafenone or amiodarone. The duration of AF, the success rate of the treatment, the need for cardioversion, the frequency of repeated AF, and the need for repeating the treatment were compared. RESULTS: The duration of the first (p=0.361), second (p=0.832), and third (p=0.298) episodes of AF, the need for cardioversion (p=0.998), and the need to repeat the first and second doses of drugs (p=0.557, 0.699) were comparable between the study groups. Repeated AF was observed in 17 patients (30.9%) in the propafenone group and 23 patients (34.3%) in the amiodarone group (p=0.704). CONCLUSION: Oral propafenone and intravenous amiodarone are equally effective in the treatment and conversion of recent-onset AF after CABG.
Amiodarone* ; Atrial Fibrillation* ; Coronary Artery Bypass* ; Coronary Vessels* ; Electric Countershock ; Humans ; Iran ; Propafenone* ; Thoracic Surgery

BACKGROUND: Propafenone is effective in the treatment of ventricular arrhythmias and paroxysmal supraventricular tachycardia. Propafenone has been shown to be also useful in preventing the recurrence of atrial fibrillation. But to date, date concerning the efficacy of propafenone for patients experiencing paroxysmal and chronic atrial fibrillation have not been examined in Korea. METHODS: In patients with paroxysmal atrial fibrillation propafenone was given at a dose of 450mg daily without dose titration and symptomatic recurrences were evaluated by patient interview during follow-up. In patients with chronic atrial fibrillation, who had no previously attempted cardioversion, propafenone was given at a dose of 450~675mg daily without dose titration, and after a minimum of 3 days pharmacological cardioversion was assessed. Those patients in whom sinus rhythm had been restored pharmacologically or by combined direct current cardioversion were followed with maintaining propafenone therapy also at a dose of 450~675mg daily. RESULTS: Of 7 patients with paroxysmal atrial fibrillation, 4 (57%) patients had marked symptomatic improvement and they were followed for 197 to 460 (mean 286) days Of 13 patients with chronic atrial fibrillation, 7 patients incuding 4 pharmacologically converted patients were initially controlled to sinus rhythm. In 5 (38%) patients maintenance of sinus rhythm was followed for 90 to 415 (mean 224) days. CONCLUSION: Although these observations were made in small number of patients and are so limited, the results are comparable to the previous studies which showed the potential role of propafenone in the management of atrial fibrillation.
Arrhythmias, Cardiac ; Atrial Fibrillation* ; Electric Countershock ; Follow-Up Studies ; Humans ; Korea ; Propafenone* ; Recurrence ; Tachycardia, Supraventricular