SURGICAL-TREATMENT OF ATRIAL-FIBRILLATION

The persistence of atrial fibrillation with a controlled ventricular r esponse with medical treatment or ablation of the His bundle, suppress es troublesome palpitations but leaves potential haemodynamic problems and the risk of thromboembolism. Surgical treatment of this arrhythmi a, by leaving an anatomic bridge between the sinus and atrioventricula r nodes, aims to allow acceleration of the ventriCular rhythm on exerc ise whilst preventing by partial, total or selective exclusion of atri al tissues, the multiple intra-atrial reentries responsible for atrial flutter or fibrillation. The first method proposed was isolation of t he left atrium (Cox, 1980) which allows acceleration of the ventricula r rhythm during exercise, leaving little or no haemodynamic disturbanc e, but, in theory, the same risk of embolism. The second method, the < < corridor >> operation (Guiraudon, 1985) consists in isolating both a tria, but significantly alters the haemodynamic efficacy without reduc in- the embolic risk, and hardly offers any advantage over ablation of the nodo-hisian pathway completed by implantation of a ventricular. r ate responsive. pacemaker. The recently described << maze >> procedure (Cox and Boineau, 1991) would seem to be more promising with judiciou sly chosen incisions (at the base of the atria, around the pulmonary v eins, between the vena cavae, along the interatrial septum, etc.) and points of cryoablation in the region of the coronary sinus, allowing m odulation of the ventricular response with activation of sufficient at rial tissue to prevent reentry and recurrence of atrial fibrillation w ithout affecting haemodynamic efficacy. The results of this technique are encouraging in the hands of its inventors but require confirmation in larger series of patients. The ideal indications of this operation merit discussion ; they concern preferentially young subjects, especi ally when other surgery is indicated (mitral valve or coronary bypass surgery), and when there is a history of recurrent embolism and absolu te contraindications to anticoagulant therapy.