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

An exercise-induced idiopathic Brugada electrocardiographic pattern during the effort phase is very rare. A 42-year-old male visited our cardiology clinic for chest discomfort. He has been treated for myocardial infarction 2 months ago. He underwent a treadmill test according to the Bruce protocol. Typical coved-type ST-segment elevation was found during the effort phase, and it gradually recovered after the exercise. The ST-segment elevation appeared to be unrelated to hypervagotonia. This elevation was not induced by a pharmacological test with flecainide. A significant ventricular arrhythmia was not induced by programmed ventricular stimulation. Hence, we discharged the patient without implantation of an implantable cardioverter defibrillator.
Adult ; Arrhythmias, Cardiac ; Cardiology ; Defibrillators ; Electrocardiography* ; Exercise Test ; Flecainide ; Humans ; Male ; Myocardial Infarction ; Thorax ; Vagus Nerve

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*

Flecainide acetate is a potent class Ic anti-arrhythmic drug with a major sodium channel-blocking effect. Flecainide toxicity can cause myocardial impairment and precipitate circulatory collapse, particularly in patients with renal failure. Electrical and hemodynamic deterioration during flecainide toxicity may not respond to conventional treatments. We report the successful management of flecainide toxicity using extracorporeal membrane oxygenation (ECMO), hemoperfusion, and bicarbonate administration maintaining alkalinity.
Extracorporeal Membrane Oxygenation ; Flecainide* ; Hemodynamics ; Hemoperfusion ; Humans ; Renal Insufficiency ; Shock ; Sodium ; Tachycardia, Supraventricular*

Dronedarone is a new antiarrhythmic drug for the treatment of nonpermanent atrial fibrillation. Compared with amiodarone, it is regarded as a safe medication due to its structural differences. In this report, we describe a 56-year-old man who developed photosensitivity due to dronedarone. He presented with itchy skin rashes for 1 week. Maculopapular exanthema was localized on the neck, both arms, and both hands, with sparing of the other parts of the body. Dronedarone was prescribed 4 weeks ago when atrial fibrillation occurred. After development of skin rashes, dronedarone was discontinued, and systemic steroid, antihistamine, and topical corticosteroid were administered for 1 week, with improvement in skin rashes. The photopatch test was performed with antiarrhythmic drugs, including dronedarone, amiodarone, and flecainide, 4 weeks after withdrawal of dronedarone. Positive reactions were recorded only to dronedarone at the site exposed to ultraviolet A. He was diagnosed with dronedarone-induced photosensitivity and advised to change the antiarrhythmic medication to others. There have been a few case reports on photosensitivity reactions due to dronedarone, which were diagnosed only by clinical suspicion. However, we suspected photosensitivity and proved it by the photopatch test. Photosensitivity should be considered in patients having skin rashes on the exposed area and taking antiarrhythmic medication, including dronedarone.
Amiodarone ; Anti-Arrhythmia Agents ; Arm ; Atrial Fibrillation ; Exanthema ; Flecainide ; Hand ; Humans ; Middle Aged ; Neck

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

We describe here a woman with Brugada syndrome revealed in postoperative period. A 48-year-old woman who underwent open biopsy of a tumor on her left distal femur under general anesthesia experienced post-surgical palpitations and chest discomfort. On the following day, an electrocardiogram showed coved type ST elevation with T inversion on V1 and V2 without any structural heart disease. After we confirmed it by a flecainide provocation test, the patient was diagnosed with Brugada syndrome. Genetic analysis showed c.3578G > A (p.Arg1193Gln) variant in the SCN5A gene. She underwent successful curettage and internal fixation under a single-shot spinal anesthesia without any adverse events.
Anesthesia, General ; Anesthesia, Spinal ; Biopsy ; Brugada Syndrome ; Curettage ; Electrocardiography ; Female ; Femur ; Flecainide ; Heart Diseases ; Humans ; Postoperative Period ; Thorax

BACKGROUND: Atrial fibrillation is one of the most common cardiac arrhythmias which has been recieved relatively little attention until recently.Despite the variety of treatment modalities including drugs,surgery,catheter ablation and devices,the overall treatment of atrial fibrillation is not always satisfactory.Phalmacotherapy is still the most commonly used treatment through the unfavorable side effects of antiarrhythmic drugs are problematic.The purpose of this study is to compare the efficacy of class Ic antiarrhythmic drugs,propafenone versus flecainide. METHODS: We treated one hundred eighteen patients with atrial fibrillation by class Ic antiarrhythmic drugs,propafenone or flecainide with/without DC cardioversion to convert to and maintain the sinus rythm. We compared the clinical findings,drug efficacy,side sffects of drugs between two groups. RESULTS: 30 patients were treated by propafenne and 88 patients by flecainide.21 and 60 patients in each group were lone atrial fibrillation,14 and 49 patients were paroxysmal atrial fibrillation.Mean duration of drug administration were 360.9,339.4 days,respectively.The convesion rate to sinus rhythm by drugs was 25.0% in propafenone group and 30.7% in flecainide group(p=NS).The 300 days-manitenance rates of sinus rhythm after conversion by drugs or DC cardioversion were 63,3%,70.4%(p=NS)respectively. The side effects of drugs were dizziness,nausia and vomitting in both group and 1st degree AV block,transient sinus node dysfunction and decreased visual acuity in flecainde group.The drugs were discontinued in 11(37.7%) and 26(29.5%) patients in each group due to recurrence of atrial fibrillation or side effects of drugs. CONCLUSION: This study suggests that propafenone and flecainide are comparably effective in maintaining sinus rhythm in atrial fibrillation patients.Futher prospective and large study is required to confirm this findings.
Anti-Arrhythmia Agents ; Arrhythmias, Cardiac ; Atrial Fibrillation* ; Electric Countershock ; Flecainide* ; Humans ; Propafenone* ; Recurrence ; Sick Sinus Syndrome ; Visual Acuity

Flecainide acetate is a potent class IC anti-arrhythmic drug with a major sodium channel blocking effect. Flecainide toxicity can cause myocardial impairment and precipitate circulatory collapse. It may also result in life-threatening arrhythmia, although cases of flecainide-induced torsades de pointes are rare. Furthermore, the electrical and hemodynamic deteriorations observed during flecainide toxicity may not respond to conventional treatments. In the present study, we report the case of a 20-year-old Korean man with flecainide poisoning, who presented with hypotension. The patient was successfully treated with sodium bicarbonate, amiodarone, MgSO₄, and lidocaine, with no recourse to extracorporeal therapy. Although there is no standard therapy for flecainide toxicity, this report demonstrates that intensive pharmacological treatment is beneficial in cases of flecainide overdose.
Amiodarone ; Arrhythmias, Cardiac ; Drug-Related Side Effects and Adverse Reactions ; Flecainide ; Hemodynamics ; Humans ; Hypotension ; Lidocaine ; Poisoning ; Shock ; Sodium Bicarbonate ; Sodium Channels ; Torsades de Pointes* ; Young Adult