INTRODUCTION: We report the case of a 36-year-old patient with a longstanding history of paroxysmal tachycardia. METHODS AND RESULTS: During the electrophysiological study, the H-V interval was prolonged in sinus rhythm, and a second potential (H'') with distal to proximal activation pattern was recorded in the region of the proximal His-Purkinje system. Two wide QRS complex tachycardias were induced, both with V-A dissociation. One application of radiofrequency energy at the site with earliest and largest H'' potential during sinus rhythm cured both tachycardias. The right and left bundle branch block morphology tachycardias were diagnosed as clockwise and counterclockwise bundle branch reentrant tachycardia. The H'' potential represented the retrograde right bundle potential during sinus rhythm and bundle branch block reentrant tachycardia.

Adult↗

PubMed2005

Cibenzoline induced Brugada ECG pattern.

We report a case of a 61-year-old female patient who presented with palpitations. The baseline electrocardiogram showed incomplete right bundle branch block with saddle back pattern of the ST segment in one precordial lead, but without any significant ST elevation. She was treated with oral cibenzoline. The subsequent ECG showed a coved Brugada ECG (type I) pattern, which resolved following the discontinuation of cibenzoline. An ajmaline test reproduced the coved type Brugada ECG pattern. Our case is the first report of oral cibenzoline therapy unmasking the diagnostic coved Brugada ECG pattern in a patient with a baseline normal ECG. Cibenzoline, a class I sodium channel blocker antiarrhythmic drug, should probably be avoided in the treatment of patients with Brugada syndrome.

Anti-Arrhythmia Agents↗

PubMed2005

Sudden cardiac death and inherited arrhythmia syndromes.

Sudden cardiac death (SCD) at youth is rare and is often caused by inherited cardiac disorders. This review focuses on the genetic background of inherited primary electrical diseases, the so-called "channelopathies." Following a short clinical description of each syndrome, the recent findings in the genetics of long QT syndrome, short QT syndrome, isolated cardiac conduction defect, familial sick sinus syndrome, familial atrial fibrillation, cathecholaminergic polymorphic ventricular tachycardia, familial Wolff-Parkinson-White (WPW) syndrome, and Brugada syndrome are discussed. The currently proposed theoretical model of overlapping phenotypes in SCN5A sodium channel mutations is presented. The recent data indicate that advances in molecular genetics, experimental and clinical electrophysiology shed some light on the genetic background of primary electrical diseases. However, it is also becoming clear that the process from a mutation of a gene to the clinical presentation of a patient is currently only partially understood and extremely complex.

Arrhythmias, Cardiac↗

PubMed2005

Sudden cardiac death: what is inside our genes?

Although sudden cardiac death in youths is generally rare, it is estimated that 10% to 20% of these deaths occur in previously healthy infants, children, adolescents and young adults without any findings on autopsy and with devastating consequences on the family. The majority of these deaths are caused by inherited arrhythmia syndromes, the so-called 'channelopathies'. In the present paper, the recent advances in the clinical and genetic background of long QT syndrome, short QT syndrome, catecholaminergic polymorphic ventricular tachycardia, Brugada syndrome and the overlapping phenotypes are reviewed, and the recently established connections between these syndromes and idiopathic ventricular fibrillation and sudden infant death syndrome are discussed.

Bundle-Branch Block↗

PubMed2003

Advances in the acute pharmacologic management of cardiac arrhythmias.

Safe and effective control of rapid ventricular rates in acute-onset atrial fibrillation (AF) can be accomplished with intravenous calcium antagonists, beta-blockers or amiodarone; digoxin is less effective. If pharmacologic cardioversion of AF is desired, single oral doses of propafenone or flecainide are safe and effective in patients without structural heart disease. Intravenous ibulitide is moderately effective in the conversion of persistent AF or atrial flutter, with a small risk of proarrhythmia. In wide QRS complex tachycardia of uncertain origin, adenosine and lidocaine are no longer recommended. Procainamide or amiodarone are the treatment options, but attempts should be made to define the origin of tachycardia. In the treatment of monomorphic ventricular tachycardia, lidocaine is no longer recommended; procainamide or amiodarone are the recommended therapies. In polymorphic ventricular tachycardia with a normal QT interval, beta-blockers are recommended. In shock-refractory ventricular fibrillation, lidocaine, and magnesium are ineffective; intravenous amiodarone should be the treatment of choice.

Anti-Arrhythmia Agents↗

PubMed2003

Strategies for reversing shock-resistant ventricular fibrillation.

PURPOSE OF REVIEW: Shock-resistant ventricular fibrillation is defined as ventricular fibrillation persisting after three defibrillation attempts. In approximately 10 to 25% of all cardiac arrests, shock-resistant ventricular fibrillation develops, and 87 to 98% of these patients die. RECENT FINDINGS: In the treatment of shock-resistant ventricular fibrillation, defibrillation using biphasic waveforms is considered as an intervention of choice. Intravenous amiodarone is also acceptable, safe, and useful, based on evidence from two randomized clinical trials. Intravenous vasopressin is acceptable and probably safe and useful, but the evidence supporting this recommendation is coming from a small, randomized clinical trial. Procainamide is acceptable but not recommended. In the presence of acute myocardial infarction and recurrent ventricular fibrillation, if all other therapies fail, beta-blockers can be considered. Magnesium, lidocaine, and bretylium are not recommended in the treatment of shock-resistant ventricular fibrillation. SUMMARY: Biphasic defibrillation and intravenous amiodarone are useful in shock-resistant ventricular fibrillation.

Adrenergic beta-Antagonists↗