COX MAZE OPERATION WITHOUT CRYOABLATION FOR THE TREATMENT OF CHRONIC ATRIAL-FIBRILLATION

Background. From August 1993 to May 1994, 20 patients (mean age, 43 ye ars) with atrial fibrillation underwent the maze operation without cry oablation. Ten patients had mitral stenosis, 5 had mitral insufficienc y, and 5 had a mixed mitral lesion. The mean left atrial diameter as m easured on echocardiograms was 6.1 cm. The cause was rheumatic in 17 p atients (85%) and degenerative in 3 (15%). Seven patients had had prev ious episodes of thromboembolism. Methods. Mitral valvuloplasty was pe rformed on 7 patients, mitral commissurotomy on 4, and mitral valve re placement on 9. Thrombi were found in the left atrium of 7 patients an d also in the right atrium in 2. The mean cross-clamp time was 73 minu tes (range, 52 to 108 minutes). Results. Patients were discharged from the hospital in good condition. Hemodynamic studies and Doppler echoc ardiograms showed significant reduction in the left atrial diameter (m ean diameter, 4.9 cm; p < 0.01) in 18 patients. The two-channel Holter monitor showed sinus rhythm in 15 patients, atrial ectopic rhythm in 4, and atrial fibrillation in 1. Eleven patients (55%) experienced atr ial fibrillation (9 in the first 3 months postoperatively), which was reversed with quinidine. Ninety percent of patients had development of an effective, synchronous, atrial systole. Six to 15 months postopera tively (average follow-up, 10 months), all patients were in functional class I, and 18 were not on a regimen of antiarrhythmic medication. C onclusions. This simplification of the maze operation has been demonst rated to be an effective alternative for the treatment of chronic atri al fibrillation.