Ventilatory efficiency measured during sub‐maximal cardiopulmonary exercise testing predicts postoperative outcomes following heart transplantation

Abstract

AbstractCardiopulmonary exercise testing is commonly used to evaluate patients for heart transplantation. We assessed the utility of ventilatory efficiency (VE/VCO2) to predict perioperative outcomes following heart transplantation. We retrospectively reviewed all patients undergoing cardiopulmonary exercise testing prior to heart transplantation at our center. Spearman's coefficient showed a correlation between VE/VCO2 and ICU free days in the first 30‐days post‐transplant (R = –.37, p < .01). A VE/VCO2 cut‐off >35 was associated with significantly lower median ICU‐free days (23.0 vs. 27 days; p < .01) and a higher likelihood of postoperative morbidity (OR = 5.64, 95% CI = 1.75–18.16; p < .01). Multiple regression analysis controlling for peak oxygen consumption and right heart catheter parameters showed VE/VCO2 >35 is independently associated with lower ICU‐free days (p < .01) and postoperative morbidity (p = .02). Peak oxygen consumption <15 mL/min/kg was not associated with higher ICU or hospital‐free days. VE/VCO2 >35 independently predicts early postoperative morbidity in patients undergoing heart transplantation.