Creation and Validation of a Novel Sex-Specific Mortality Risk Score in LVAD Recipients

• Type of Material: Article
• Authors: Aditi Nayak, Emory University; Yingtian Hu, Emory University; Yi-An Ko, Emory University; Rebecca Steinberg, Emory University; Subrat Das, Icahn School of Medicine; Anurag Mehta, Emory University; Chang Liu, Emory University; John Pennington, University of Alabama Birmingham; Rongbing Xie, University of Alabama Birmingham; James K Kirklin, University of Alabama Birmingham; Robert L Kormos, University of Pittsburgh; Jennifer Cowger, Henry Ford Hospital; Marc A Simon, University of Pittsburgh; Alanna Morris, Emory University
• Language: English
• Date: 2021-04-06
• Publisher: WILEY
• Publication Version: Final Published Version
• Copyright Statement: © 2021 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.
• License: Creative Commons Attribution-NonCommercial 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1161/JAHA.120.020019
• Title of Journal or Parent Work: JOURNAL OF THE AMERICAN HEART ASSOCIATION
• Volume: 10
• Issue: 7
• Start Page: e020019
• End Page: e020019
• Grant/Funding Information: Dr Morris is supported by funding from the National Institutes of Health/National Heart, Lung, and Blood Institute (K23 HL124287, R03 HL146874) and the Robert Wood Johnson Foundation (Harold Amos Medical Faculty Development Program). Dr Mehta is supported by American Heart Association grant 19POST34400057 and the Abraham J. & Phyllis Katz Foundation. J. Pennington is supported by the Society of Thoracic Surgeons and World Society for Pediatric and Congenital Heart Surgery. Dr Simon is supported by NIH grants 1R01AG058659, 2P01HL103455, and UL1 TR001857.
• Keywords: PREDICTING SURVIVAL; left ventricular assist device; Cardiovascular System & Cardiology; risk score; HEART-FAILURE; Life Sciences & Biomedicine; DISEASE; IMPLANTATION; VENTRICULAR ASSIST DEVICE; sex disparity; MODEL; OUTCOMES; SUPPORT; prognosis; Science & Technology; CARE; REGISTRY; Cardiac & Cardiovascular Systems; mortality
• Research Categories: Health Sciences, Medicine and Surgery; Health Sciences, Epidemiology

Abstract

BACKGROUND: Prior studies have shown that women have worse 3-month survival after receiving a left ventricular assist device compared with men. Currently used prognostic scores, including the Heartmate II Risk Score, do not account for the increased residual risk in women. We used the IMACS (International Society for Heart and Lung Transplantation Mechanically Assisted Circulatory Support) registry to create and validate a sex-specific risk score for early mortality in left ventricular assist device recipients. METHODS AND RESULTS: Adult patients with a continuous-flow LVAD from the IMACS registry were randomly divided into a derivation cohort (DC; n=9113; 21% female) and a validation cohort (VC; n=6074; 21% female). The IMACS Risk Score was developed in the DC to predict 3-month mortality, from preoperative candidate predictors selected using the Akaike information criterion, or significant sex × variable interaction. In the DC, age, cardiogenic shock at implantation, body mass index, blood urea nitrogen, bilirubin, hemoglobin, albumin, platelet count, left ventricular end-diastolic diameter, tricuspid regurgita-tion, dialysis, and major infection before implantation were retained as significant predictors of 3-month mortality. There was significant ischemic heart failure × sex and platelet count × sex interaction. For each quartile increase in IMACS risk score, men (odds ratio [OR], 1.86; 95% CI, 1.74– 2.00; P<0.0001), and women (OR, 1.93; 95% CI, 1.47– 2.59; P<0.0001) had higher odds of 3-month mortality. The IMACS risk score represented a significant improvement over Heartmate II Risk Score (IMACS risk score area under the receiver operating characteristic curve: men: DC, 0.71; 95% CI, 0.69– 0.73; VC, 0.69; 95% CI, 0.66– 0.72; women: DC, 0.73; 95% CI, 0.70– 0.77; VC, 0.71 [95% CI, 0.66– 0.76; P<0.01 for improvement in receiver operating char-acteristic) and provided excellent risk calibration in both sexes. Removal of sex-specific interaction terms resulted in significant loss of model fit. CONCLUSIONS: A sex-specific risk score provides excellent risk prediction in LVAD recipients.