As for the preceding years, important studies regarding several remaining clinical issues for electrophysiologists have been reported in 2004. Large randomized studies have underlined the need for an EP study in asymptomatic patients with overt ventricular preexcitation. In addition to a short antegrade refractory period,
arrhythmia induction (
atrial fibrillation or
reciprocating tachycardia) argues for accessory pathway ablation. Although currently leading to fairly good results,
atrial fibrillation ablation technique is still evolving. Encircling pulmonary vein and the surrounding atrial tissue seems to give better long term clinical results as compared to ostial pulmonary vein disconnection. Large series have confirmed that whatever
cardiomyopathy etiology, prophylactic ICD implantation was associated with a reduction of sudden arrhythmic death during follow-up in patients with low ejection fraction. However, in order to save one patient more and more patients have to be implanted because of the increasing efficacy of pharmacological treatment for
heart failure. Three clinical series of
arrhythmogenic right ventricular dysplasia implanted with AICD have been published this year. The prognostic factors for the occurrence of severe ventricular
arrhythmia are hemodynamically ill tolerated
ventricular tachycardia, and VT induction during EP study. Management of patients with
Brugada syndrome is still far from being well defined. Interestingly in a recent report,
hydroquinidine has been found to reduce the incidence of ventricular
arrhythmia in the follow-up as well as the rate of ventricular
arrhythmia induction in the EP lab. Yet, prophylactic ICD implantation remains the treatment of choice in symptomatic and inducible patients.