Surgery in patients of severe aortic stenosis with low transvalvular gradients and severe left ventricular dysfunction

Objective To assess the result of aortic valve replacement(AVR) for patients of severe aortic stenosis(AS)with low transvalvular gradients(TVG) and severe left ventricular dysfunction,and try to identify the determinants of survival,functional status and change in left ventricular ejection fraction(LNEF) during follow-up.Methods From 2005 to 2011,35patients with aortic valve area(AVA) ＜ 1 cm2,LN EF ＜ 0.40 and mean TVG ＜ 30 mm Hg underwent AVR in our hospital.The average age of the patients was 58 yeats old,and 88.6％ of the patients were in New York Heart Association (NYHA) functional class Ⅲ/IV at admission to the hospital.The AVA was (0.70 ± 0.09) cm2,LVEF was 0.276 ± 0.020,TVG was (26.0 ± 2.3) mm Hg,and left ventricular end-diastolic diameter (LNEDD) was (6.3 ±0.4) cm respectively.35 prosthetic valves were implanted,including 20 mechanical prostheses and 15 biological prostheses with the mean sizs of (23 ± 1) mm.Concomitant procedures included mitral valvularplasty in 5.tricuspid valve repair in 3 and coronary artery bypass grafting in 4.Results The perioperative mortaiity was 8.6％.Follow-up period was 3 to 60 monthes.The survival rates were:1-year 78％,2-year 68％,5-year 60％.LVEF increased significantly to 0.358 ± 0.047 one week postoperatively (P =0.008) and 0.426 ± 0.031 six months later (P ＜ 0.01)).LNEDD decreased to (5.7 ± 0.4) cm one week later(P =0.062) and (5.3 ±0.3)cm 6 months postoperatiwely (P ＜ 0.01).NYHA functional class improved from 88.6％ in class Ⅲ/Ⅳ to 35％ (P ＜0.01).Compared with those who surviwd during follow-up,the patients who died during follow-up were older in the year of operation[(63 ± 10) vs (54 ± 11),P =0.017],their NYHA functional class was higher[(3.9 ±0.2) vs (2.9 ±0.3),P =0.003]and the LVEDD for them in one week postoperatively was larger[(6.0 ± 1.0) cm vs (5.5 ± 0.3) cm,P =0.031].Conclusion The left ventricle contractile reserve seems to play an essential role for surgery in patients of severe aortic stenosis with low transvalvular gradients and severe left ventricular dysfunction.AVR can be performed for them with acceptable results. Key words: Aortic valve stennsis; Heart Valve Prosthesis Implantation; Ventricular Dysfunction,Left