Relationship Between Preoperative Diastolic Transpulmonary Gradient With Pulmonary Vascular Resistance and 1-Year and Overall Mortality Rates Among Patients Undergoing Cardiac Transplant

Cardiac transplant is a life-saving procedure for patients with end-stage heart failure. Preoperative pulmonary vascular resistance is indicative of intrinsic pulmonary vascular disease and correlates with posttransplant survival. However, its measurement is costly and time consuming. Therefore, simpler techniques are required. Diastolic transpulmonary gradient reportedly indicates intrinsic pulmonary vascular disease. Here, we investigated the relationship between preoperative diastolic transpulmonary gradient with preoperative pulmonary vascular resistance and 1-year and overall mortality among cardiac transplant patients. Fifty-one patients who underwent cardiac transplant between 2006 and 2017 were included. All patients underwent preoperative right and left heart catheterization and oxygen study. Among these, diastolic transpulmonary gradient, mean transpulmonary gradient, and pulmonary vascular resistance were correlated with one another and 1st-year and overall mortality rates. Patients were grouped according to whether they received diastolic transpulmonary gradient or not, and both groups were compared with respect to 1-year and overall mortality. Binary logistic regression analysis was done to test whether diastolic transpulmonary gradient was a significant predictor of 1-year and overall mortality. Mean patient age was 45.5 ± 9.8 years. The 1-year and overall mortality rates were 21.6% (11/51) and 37.3% (19/51), respectively. Diastolic transpulmonary gradient was significantly correlated with pulmonary vascular resistance, 1-year mortality, and overall mortality (P < .05) and was a significant predictor of 1-year and overall mortality (odds ratio 6.0; 95% confidence interval, 1.4-25.3; P < .05 and odds ratio 4.8; 95% CI, 1.4-17.5; P < .05, respectively). Patients with a diastolic transpulmonary gradient of ≥ 7 mm Hg had significantly higher 1-year and overall mortality (P < .05). Diastolic transpulmonary gradient can be used as a promising easy-to-use parameter of intrinsic pulmonary vascular disease and a predictor of 1-year and overall mortality among patients undergoing cardiac transplant.