Can echocardiographic parameters effectively predict elevated pcwp in heart transplant patients?

Abstract

Funding Acknowledgements Type of funding sources: None. PCWP measurement remains the gold standard for the diagnosis of Heart Failure with preserved ejection fraction. Nevertheless, right heart catheterization (RHC) is a last step procedure nowadays, with most of the patients diagnosed solely by transthoracic echocardiography (TTE) parameters, as it is widely available and not associated with the risks of the invasive procedures. Heart transplant (HT) patients, on the other hand, routinely perform RHC as follow-up for rejection surveillance, allowing frequent invasive hemodynamic assessment. Purpose Evaluate the association between TTE parameters and the invasively measured pulmonary capillary wedge pressure (PCWP) by RHC in HT patients. Methods A retrospective analysis of consecutive HT patients submitted to RHC between February 2016 and November 2021, who previously performed TTE, was made. The area under the curve (AUC) was performed to evaluate the association between several TTE parameters (left ventricular (LV) end-diastolic diameter (LV EDD), LV end-systolic diameter (LV ESD), LV ejection fraction (LV EF), interventricular septum wall thickness (ST), LV global longitudinal strain (GLS), left atrium volume index (LAVi), transmitral E/A ratio (E/A), LV E/e’ ratio (E/e’), E velocity deceleration time (DT), isovolumetric relaxation time (IV RT), tricuspid annular plane systolic excursion (TAPSE) and systolic pulmonary artery pressure (sPAP)) and elevated PCWP (defined as >15mmHg). Statistical differences with a p-value <0.05 were considered significant. Results A total of 127 RHC were performed during the study period. Mean age was 50 years, 79% (n=100) were male, mean LV EF 58 ± 10% and mean BNP 808 ± 984 pg/mL. Mean PCWP was 12 ± 6 mmHg, with 28% (n=35) with a value higher than 15mmHg. AUC results of several TTE parameters for the prediction of elevated PCWP are depicted in Table 1. LV EF (AUC 0.702, p = 0.001) and GLS (AUC 0.768, p = 0.07) were significantly correlated with elevated PCWP, while the remaining parameters failed to do so. Conclusion In this HT group, several TTE indices commonly employed for non-invasive estimation of increased intraventricular pressures, including E/e', E/A ratio, LAVi, and sPAP, showed a poor correlation with elevated PCWP. GLS, a TTE parameter widely used to assess subclinical dysfunction were the parameter with the most robust association with elevated PCWP in this population, demonstrating that it has the potential to be used in routine clinical practice.