Right ventricular (RV) failure is the major cause of mortality in pulmonary hypertension (PH). Diastolic stiffness is significantly associated with outcomes in patients with PH. Cardiac magnetic resonance (CMR) imaging provides an opportunity to image the right ventricle and quantify right heart remodeling. The Ohio State University (OSU) CMR registry includes images, imaging data (ventricular volumes) and vital status. The aim of this study was to investigate the association of right ventricular diastolic stiffness and function with mortality in patients with PH. Patients were identified from the OSU CMR registry by searching the CMR summary statements for keyword close variants of ‘pulmonary hypertension’. Right heart catheterization (RHC) data were collected from retrospective chart review. The RV diastolic stiffness (β) was calculated using the relationship, P = α(eβV − 1), a fitting constant (α), right atrial pressure, end-systolic (ESV) and end-diastolic (EDV) volumes. Arterial afterload (Ea) was the ratio of end-systolic pressure to stroke volume. Pulmonary hypertension was defined as a mean pulmonary artery pressure ≥ 20 mmHg. The putcome was defined as death, with the index date as the CMR date. Data were presented as the mean ± SD, median [interquartile range] or number (percentage) when appropriate. Univariable Cox models were used to test the association of RV function with outcomes. In participants with complete CMR and RHC data (n = 111; age 55 ± 15 years; body surface area 1.96 ± 0.28 m2; 62% female), there was a median follow-up time of 3.23 [1.03–6.06] years (41 events). Within patients with PH (86.5%), 60 had a wedge pressure ≤ 15 mmHg. End-diastolic elastance (Eed) was increased in patients with PH and highest in patients with an elevated wedge compared with no PH. In the PH group with a wedge pressure ≤ 15 mmHg, Eed, RVEF and SV/ESV were associated with morality. The RV diastolic stiffness is increased in PH and is significantly associated with mortality in patients with pulmonary hypertension.
Alexandra Janowski, Charles Fauvel, Scott Visovatti, Raymond L. Benza, Rebecca R. Vanderpool, Division of Cardiovascular Medicine, The Ohio State University, Columbus, OH, USA