Impact of obesity on long-term survival after aortic valve replacement with small prosthesis

Abstract

Objective This study was designed to evaluate the effect of obesity on late survival after aortic valve replacement(AVR) in patients with implantation of small aortic prosthesis(size≤21).Methods From January 1998 through December 2008,307 patients in a single center in china underwent primary AVR with smaller prosthesis survive the 30 days of surgery.Patients were defined as normal if body mass index (BM1) ＜ 24.0 kg/m2,as overweight if BMI 24.0-27.9 kg/m2,and as obesity if BMI≥28.0 kg/m2.Data of New York Heart Association(NYHA) Functional class,effective orifice area index (EOAI),left ventricular mass index(LVMI),left ventricular ejection fraction(LVEF) were got at the 3rd month(M),6th M,1 st year(Y),3rd Y,5th Y,8th Y after operation respectively.Results At multivariable analysis,obesity was independent factor of later mortality [hazard ratio (HR):1.62 ; P =0.01].Obesity group and overweight group had poor survival (P ＜0.001)and higher proportion of NYHA Function Ⅲ/Ⅳ (P ＜ 0.01) in long-term compared to normal group.EOAI were lower and LVMI were higher in obesity group and overweight group,but LVEF have no significant difference.Conclusion Obesity is associated with increased late mortality after AVR in patients with implantation of small aortic prosthesis.Obesity and overweight may also affect the NYHA function in long term.EOAI should be improved where possible as it may reduce late mortality and improve life quality in such patients. Key words: Heat valve posthesis implantation; Aortic valve; Obesity; Body mass index