Restoration of atrial mechanical function after maze operation in patientswith structural heart disease

Background The maze operation is effective for the restoration of sinus rhy thm; however, restoration of atrial mechanical function has not been demons trated in all patients. Methods Maze operations were performed in 32 patients (13 men, 19 women; me an age 47.1 +/- 9.0 years) combined with valvular surgery (n = 25), coronar y artery bypass graft (CABG) (n = 3), and others (n = 4). At 1 week, 3 mont hs, 6 months, and 1 year after the operation, prospective serial Doppler ec hocardiographic examination was carried out to determine the presence of at rial mechanical function. Results sinus rhythm was restored and maintained during the follow-up perio d in 26 (81%) patients; in 22 patients this was due solely to the operation , whereas in four patients an antiarrhythmic agent was needed to maintain s inus rhythm. Another four patients showed paroxysmal atrial fibrillation (A F) despite treatment with an antiarrhythmic agent. Right atrial mechanical function was restored in all 30 patients with sinus rhythm or paroxysmal AF ; in 19 (63%) of these, left atrial mechanical function was restored. In pa tients with restored left atrial mechanical function, peak A velocity (A) a nd A/E ratio (A/E) of mitral inflow were significantly lower than in the 16 postoperative control patients (A: 0.46 +/- 0.14 m/sec vs 0.75 +/- 0.29 m/ sec, p < 0.01; A/E: 0.40 vs 0.80, p < 0.01). In patients with left atrial m echanical function, the duration of AF was significantly shorter than in pa tients without left atrial mechanical function (1.9 +/- 2.9 years vs 7.1 +/ - 3.0 years, p < 0.01), but there were no significant differences in left a trial size and volume. Conclusions The maze operation could be safely added to standard open heart surgery for the correction of underlying structural heart disease. The rat e of conversion to sinus rhythm resulting solely from the operation might b e lower than the rates previously reported with only the duration of AF adv ersely affecting the restoration of left atrial mechanical function. Consid ering the fact that not all patients converted to sinus rhythm show atrial mechanical function, the role of the maze operation in the prevention of sy stemic embolism, with subsequent improvement in survival, requires further study.