A COMPARISON OF GUIDELINES FOR HEART TRANSPLANT CONSIDERATION BASED ON CPET DATA

Abstract

https://youtu.be/tfol-46xG-o BACKGROUND The International Society for Heart and Lung Transplantation (ISHLT) recommends using peak oxygen uptake (VO2≤12 mL/kg/min), percent predicted peak VO2 (ppVO2≤50%), or the ventilation to carbon dioxide slope (VE/VCO2 slope>35) to guide listing for heart transplantation (HTx) in patients with heart failure with reduced ejection fraction (HFrEF). Data comparing the mortality rates between each of these thresholds is lacking. The purpose of this retrospective cohort study was to describe the 3-year mortality rate among patients with HFrEF based on the ISHLT recommendations. METHODS This was a secondary analysis of a combined cohort of patients (≥18 years) with HFrEF from Henry Ford Hospital (n=1,063) and the HF-ACTION study (n=1,772). The cohort was limited to patients who completed a cardiopulmonary exercise test on a treadmill and were prescribed a beta-adrenergic blockade at the time of the test. The primary outcome was probability of all-cause mortality at 3 years based on Kaplan-Meier estimates. Patients were censored at the date of HTx, left ventricular assist device implant, or last known alive. Mortality rates were calculated for patients with a peak VO2≤12 mL/kg/min, ppVO2≤50%, and VE/VCO2 slope>35. The cohort was stratified by sex, age, obesity (body mass index [BMI]> 30 kg/m2), and peak respiratory exchange ratio (RER). Mortality rates were compared to the 3-year mortality post HTx reported by ISHLT. RESULTS In our combined cohort (n=2,775; age=57±13 y; 19% women; 48% non-white), 3-year mortality for peak VO2≤12 mL/kg/min, ppVO2≤50%, and VE/VCO2 slope>35 was 30%, 31%, and 28%, respectively. Each of these are higher than the 3-year mortality post HTx (20%). Similar results were observed by age below/above 50 y, BMI < versus > 30 kg/m2, RER ≤ versus >1.05, and within men. However, among women the 3-year mortality was 18% for peak VO2≤12 mL/kg/min, 25% for ppVO2≤50%, and 21% for VE/VCO2 slope>35. CONCLUSIONS ISHLT recommendations to guide listing for HTx for peak VO2≤12 mL/kg/min, ppVO2≤50%, and VE/VCO2 slope>35 are associated with a higher 3-year mortality than patients post HTx irrespective of age, obesity, and RER. However, among women only ppVO2≤50% and VE/VCO2 slope>35 identify patients with 3-year mortality that is higher than HTx.