| Popis: |
The persistence of atrial fibrillation with a controlled ventricular response with medical treatment or ablation of the His bundle, suppresses troublesome palpitations but leaves potential haemodynamic problems and the risk of thromboembolism. Surgical treatment of this arrhythmia, by leaving an anatomic bridge between the sinus and atrioventricular nodes, aims to allow acceleration of the ventricular rhythm on exercise whilst preventing by partial, total or selective exclusion of atrial tissues, the multiple intra-atrial reentries responsible for atrial flutter or fibrillation. The first method proposed was isolation of the left atrium (Cox, 1980) which allows acceleration of the ventricular rhythm during exercise, leaving little or no haemodynamic disturbance, but, in theory, the same risk of embolism. The second method, the "corridor" operation (Guiraudon, 1985) consists in isolating both atria, but significantly alters the haemodynamic efficacy without reducing the embolic risk, and hardly offers any advantage over ablation of the nodo-hisian pathway completed by implantation of a ventricular, rate responsive, pacemaker. The recently described "maze" procedure (Cox and Boineau, 1991) would seem to be more promising with judiciously chosen incisions (at the base of the atria, around the pulmonary veins, between the vena cavae, along the interatrial septum, etc.) and points of cryoablation in the region of the coronary sinus, allowing modulation of the ventricular response with activation of sufficient atrial tissue to prevent reentry and recurrence of atrial fibrillation without affecting haemodynamic efficacy. The results of this technique are encouraging in the hands of its inventors but require confirmation in larger series of patients.(ABSTRACT TRUNCATED AT 250 WORDS) |
