Does body size affect a successful bridge to heart transplantation by long-term continuous-flow ventricular assist device support?
Minoru Ono1, Osamu Kinoshita1, Mitsutoshi Kimura1, Haruo Yamauchi1, Shogo Shimada1, Masahiko Ando1, Masaru Hatano2, Eisuke Amiya2, Issei Komuro2.
1Department of Cardiovascular Surgery, The University of Tokyo, Tokyo, Japan; 2Department of Cardiovascular Medicine, The University of Tokyo, Tokyo, Japan
Objective: Continuous-flow ventricular assist device (cf-VAD) enables end-stage heart failure patient await heart transplantation (HTx) for extended period of time. Long-term support by cf-VAD, however, may be complicated by several complications which lead to off-list of HTx or even death. Waiting time in Japan has been prolonged due to a severe donor shortage, and support duration of cf-VAD is extremely long. We sought to examine whether body size affects a successful bridge to HTx (BTT) under such a circumstance.
Patients and Methods: Since November 2007, 185 patients were implanted with cf-VAD as a BTT. There were 43 females (23%) with an average age of 41.1 years. Patients were divided into 3 groups, based on 2 body size categories; body mass index (BMI) to Group T (18.5 or less), N (18.5 to < 25.0) and O (25.0 or over), and body surface area (BSA) to Group S (< 1.5), M (1.5 to < 1.7) and L (1.7 or over). Successful bridge is defined as HTx, weaning from cf-VAD with recovery of function, ongoing support with HTx eligibility. Successful outcome rates are compared among groups. Survival was estimated by Kaplan-Meier method and compared by long-rank test. Statistical significance was judged as p < 0.05.
Results: Jarvik 2000 was used significantly more frequently, and there was more female patients in Group T and Group S. Otherwise, there was no difference in demographic data. Overall, 70 patients reached HTx, 10 were weaned, 84 ongoing support (81 with HTx eligibility) and 21 dead with survival rate of 93.7 %, 90.1 % and 88.1% at 1, 2 and 3 years, respectively. Mean support duration was 874 days with 34 patients experiencing longer-than-4-year support. There was no significant difference in either body size parameter with regard to successful outcomes. No significant difference was observed among groups in either body size parameter in survival rate.
Conclusions: There was no significant difference in favorable outcomes and survival after cf-VAD implantation as a BTT among groups divided by either BMI or BSA. Our results may infer that contemporary cf-VAD be safe and effective for BTT in wide range of body size including small and/or thin one.
