Association of Heart Rhythm With Exercise Capacity After Operation for Chronic Mitral Regurgitation

作者：Lee Seung Pyo; Kim Yong Jin^*; Lee Joo Myung; Hwang Ho Young; Kim Hyung Kwan; Kim Kyung Hwan; Kim Ki Bong; Sohn Dae Won; Ahn Hyuk; Oh Byung Hee; Park Young Bae

来源：Annals of Thoracic Surgery, 2012, 93(6): 1888-1896.

DOI：10.1016/j.athoracsur.2012.01.113

Background. Although atrial fibrillation (AF) and decreased exercise capacity are common in chronic mitral regurgitation patients, the relationship between rhythm status and exercise capacity after corrective surgery is largely unknown.
Methods. Seventy-one patients undergoing repair or replacement of mitral valve for chronic severe mitral regurgitation were examined with preoperative and 6 months' postoperative cardiopulmonary exercise test and two-dimensional echocardiography. Patients were divided into three groups according to preoperative versus postoperative rhythm (sinus/sinus, SS [n = 42]; AF/sinus, AS [n = 17]; AF/AF, AA group [n = 12]).
Results. Preoperative maximal oxygen consumption was lower and ventilatory efficiency was higher in the AS and AA groups compared with the SS group. However, maximal oxygen consumption improved only in the AS group at 6 months' postoperative cardiopulmonary exercise test (24.0 +/- 6.9 versus 24.6 +/- 6.1 mL center dot kg(-1) center dot min(-1) in the SS group, 19.3 +/- 5.9 versus 23.2 +/- 6.4 mL center dot kg(-1) center dot min(-1) in the AS group, 19.8 +/- 5.4 versus 18.8 +/- 5.1 mL center dot kg(-1) center dot min(-1) in the AA group; p = 0.016 for maximal oxygen consumption by analysis of covariance) as well as ventilatory efficiency. Echocardiography verified more significant reduction of left atrial volume in the SS and AS groups than in the AA group (172.2 +/- 68.0 versus 96.7 +/- 31.0 mL in the SS group, 247.5 +/- 77.8 versus 129.2 +/- 25.7 mL in the AS group, 316.7 +/- 210.0 versus 192.0 +/- 95.0 mL in the AA group; p = 0.001 for left atrial volume by analysis of covariance) as well as pulmonary artery systolic pressure. When analyzed for significant predictors of postoperative maximal oxygen consumption, being in the AS group but not the SS group was a significant positive predictor when compared with the AA group (beta = 5.475; p = 0.006).
Conclusions. Successful sinus conversion of AF, preferably by maze operation, in patients undergoing surgical correction of chronic severe mitral regurgitation confers improved exercise capacity. Reduction of left atrial volume and pulmonary artery pressure may contribute to this improvement.

• 出版日期2012-6