[Role of ablation in the treatment of ventricular tachycardia].
Radiofrequency ablation of ventricular tachycardia in cardiopathy essentially concerns the post-infarct period, but also dilated cardiopathy and arrhythmogenic right ventricular dysplasia. This technique relies greatly on the new computer assisted mapping techniques and intracardiac navigation. The mechanism is usually a macro-reentry which is formed on contact with a scarred, fibrous or dysplastic area. The activation site has a figure of eight appearance with a slow conduction zone activated in diastole and surrounded by areas of anatomical or functional block. This protected isthmus can be confirmed with exercising manoeuvres. Failing that, it can be identified by indirect criteria, notably when the tachycardia is not triggered or not tolerated haemodynamically. The success rates are higher in trained centres, and the morbidity/mortality of such procedures are low. Ablation is aimed at continuous or frequent tachycardias in order to limit interventions in patients fitted with an implanted defibrillator. Radiofrequency ablation in the case of idiopathic ventricular tachycardia is different because it is relatively easy when there is a right infundibular origin or a fascicular ventricular tachycardia, which is usually derived from the left posterior hemibranch conduction tissue. The situation is more delicate in the case of atypical localisation. Faced with this type of symptomatic tachyacardia, ablation is a fall-back method after failure of medical treatment.
Lacroix
D
D
Université de Lille II, cardiologie A, hôpital cardiologique de Lille. dlacroix@chru-lille.fr
D002311:Cardiomyopathy, Dilated / Q000150:complications; D017115:Catheter Ablation / Q000379:methods*; D003971:Diastole; D006801:Humans; D009203:Myocardial Infarction / Q000150:complications; D011379:Prognosis; D017180:Tachycardia, Ventricular / Q000503:physiopathology* / Q000601:surgery*