Modification of the Cox-Maze III Procedure

Kim, Ki Bong; Huh, Jae Hak; Chang, Ji Min; Lee, Jeong Sang; Ahn, Hyuk; Sohn, Dae Won

Abstract

BACKGROUND
The extended operative time needed for surgery in complicated atrial incision may preclude application of the Cox-Maze III procedure(CM-III) as a concomitant operation with standard open heart surgery. MATERIALS AND METHOD: We have modified the CM-III by : (1) obliterating the left atrial(LA) appendage instead of excising it, (2) cryoablating the bridge between the LA appendage and margin of pulmonary vein encircling incision, (3) extending the lateral incision of right atrium(RA) onto the RA appendage without excising the RA appendage, and (4) omitting the T-incision of the RA from the lower portion of posterior longitudinal right atriotomy. To assess the simplicity and efficiency of our modifications, we compared the clinical results of the conventional CM-III(group I) with those of the modified CM-III(group II) performed in patients with rheumatic mitral valve(MV) disease. RESULT: In group I(n=18), the combined procedures were mitral valve replacement(MVR) in 10, MV repair in 3, MVR and tricuspid annuloplasty(TAP) in 3, and redo-MVR in 2 patients. In group II(n=23), the combined procedures were MVR in 7, MV repair in 5, MVR and TAP in 1, and redo-MVR in 10 patients. Mean aortic cross clamp(ACC) times were 135 +/-29 minutes and 104 +/-18 minutes, and cardiopulmonary bypass(CPB) times were 240 +/-33 minutes and 185 +/-42 minutes in group I and group II, respectively. All patients were followed for a mean duration of 47 +/-14 and 29 +/-4 months after the operation in group I and group II, respectively. In group I, sinus rhythm was restored in 16 patients(88.9 %). One patient remained in AF and another patient needed pacemaker implantation due to sick sinus syndrome. In group II, sinus rhythm was restored in 21 patients(91.3 %) and AF in 2 patients. In group I, RA contractility was demonstrated in 100% of patients(16/ 16) and LA contractility in 75%(12/ 16) in the latest follow-up echocardiography. In group II, RA contractility was demonstrated in 100 % of patients(21/22) and LA contractility in 76.2% (16/21).
CONCLUSION
Our modified CM-III showed comparable sinus conversion rates and incidence of atrial contractility restoration with significantly shorter ACC time(p<0.005) and CPB time(p<0.001) than the conventional CM-III.