Long-term prognostic factors after aortic valve replacement of severe aortic stenosis

Lee, Ju Yong; Ha, Jong Won; Chang, Byung Chul; Kang, Seok Min; Rim, Se Joong; Chung, Namsik; Shim, Won Heum; Cho, Seung Yun; Kim, Sung Soon

Abstract

Background
The long term prognostic factors of aortic valve replacement (AVR) in patients with severe aortic stenosis (AS) with normal and low left ventricular function are not well known in Korean population
METHODS
Between 1990 and 1999 , 73 patients (52 male, 21 female, mean age: 58+/-10.7) with severe AS underwent AVR in Yonsei cardiovascular hospital. Patients were excluded if they had concomitant valvular operations other than AVR, previous AVR, or more than moderate amount aortic valve regurgitation, and under 18 years old. Overall survival was estimated by the Kaplan-Meier method, and the Cox proportional hazards model analyzed the predictors that influence long-term survival.
RESULTS
The causes of aortic stenosis were degenerative (44 case, 60%), congenital (26 case, 36%), and rheumatic (3 case, 4%). The preoperative characteristics (mean+/-SD) included ejection fraction (EF), 58+/-16.5%: mean aortic pressure gradient, 63+/-20 mmHg: aortic valve area, 0.62+/-0.13cm2. Simultaneous coronary artery bypass surgery and percutaneous transluminal coronary angioplasty were performed in 8 cases and 2 cases, respectively. The comparative results of the pre/post operative echocardiography of the total patients showed a significant improvement: EF of 58+/-17/64+/-12%, aortic valve area(AVA) of 0.64+/-0.15/1.54+/-0.63 cm2, mean pressure gradient (MPG) of 63+/-21/23+/-13mmHg, left ventricular end-diastolic dimension (LEEDD) of 54+/-9/50+/-9mmHg, left ventricular posterior wall thickness in systole (LV-PW) of 18+/-2/16+/-2mm. The comparative results of the pre/post operative echocardiography of low EF patients (<35%) also showed a significant improvement: EF of 30+/-4/55+/-15%, AVA of 0.59+/-0.14/ 1.67+/-0.85 cm2, MPG of 52+/-20/ 21+/-12 mmHg, LVEDD of 58+/-8/ 51+/-6 mm. Operative (30-day) mortality was 2.7% (2 of 73 patients). Six additional patients died during follow-up. The survival of patients group was 86% at 5 years and 78% at 10 years. The predictors of long-term postoperative survival were preop-EF (p<0.05,R=0.26) and presence of significant coronary artery disease (CAD) (p<0.01,R=0.35).
CONCLUSION
Postoperative long-term survival of the severe AS after AVR was negatively related to reduced preop-EF and presence of significant CAD. Therefore, the early operative treatment before the occurrence of irreversible left ventricular dysfunction and concomitant appropriate management of coronary artery disease is necessary for the improvement of the survival after AVR.