Impact of Cox maze procedure on outcome in patients with atrial fibrillation and mitral valve disease

AbstractObjective: We sought to determine whether the Cox maze procedure provides additional benefit to patients with atrial fibrillation undergoing mitral valve operations. Methods: Between May 1992 and August 2000, we performed 258 Cox maze procedures with mitral valve replacement (n = 147) or mitral valve repair (n = 111). We compared the outcomes of these patients with those of 61 control patients with preoperative atrial fibrillation who underwent mitral valve replacement alone during the same interval. The three cohorts were similar in age, sex, and proportion of patients in preoperative New York Heart Association functional class 3 or 4. Results: Although 5-year survivals were similar among the groups (94% for mitral valve replacement alone, 95% for mitral valve replacement plus maze, and 97% for mitral valve repair plus maze), freedoms from atrial fibrillation at 5 years were significantly higher in the mitral valve replacement plus maze group (78%) and the mitral valve repair plus maze group (81%) than in the mitral valve replacement group (6%, P <.0001). Freedoms from stroke at 5 years were 97% for the mitral valve replacement plus maze group, 97% for the mitral valve repair plus maze group, and only 79% for mitral valve replacement group (P <.0001). Multivariable analysis with Cox hazard model revealed that the most significant risk factor for late stroke was the omission of the Cox maze procedure (P =.003). Conclusions: The addition of the Cox maze procedure to mitral valve repair and replacement was safe and effective for selected patients. Elimination of atrial fibrillation significantly decreased the incidence of late stroke.J Thorac Cardiovasc Surg 2002;124:575-8

Plasma atrial natriuretic peptide concentration inversely correlates with left atrial collagen volume fraction in patients with atrial fibrillation Plasma ANP as a possible biochemical marker to predict the outcome of the maze procedure

AbstractObjectivesWe hypothesized that the plasma atrial natriuretic peptide (ANP) level reflects atrial degenerative change and may predict the outcome of the maze procedure.BackgroundAlthough a larger preoperative left atrial dimension and longer duration of atrial fibrillation (AF) have been reported in patients with persistent AF than in those with sinus rhythm (SR), these individual factors were not enough to predict the outcome of the maze procedure.MethodsPreoperative plasma ANP levels were measured in consecutive 62 patients who underwent the Kosakai’s modified maze procedure. Moreover, we performed histological and molecular biological examinations in the resected left atrial tissues.ResultsThe preoperative plasma ANP was lower in the AF group (n = 13) than it was in the SR group (n = 49) (p < 0.001). Multiple logistic regression analysis revealed that duration of AF and plasma ANP were independently associated with postoperative cardiac rhythm. Among 41 patients with a higher plasma ANP or shorter duration of AF than the median value, SR was restored in 95% of patients. In contrast, in 21 patients with a lower plasma ANP and a longer duration of AF than the median value, SR was restored only in 48% of patients. Histological examination revealed that the collagen volume in the left atrial tissue was higher in AF than it was in SR and inversely correlated with plasma ANP. In addition, the messenger RNA expressions of ANP, collagen type I and type III were lower in AF than they were in SR.ConclusionsThese results suggest that a combination of plasma ANP and/or duration of AF may predict the success rate for the maze operation. Advanced atrial degenerative change may result in a decrease of atrial ANP secretion