Mean pulmonary artery pressure using echocardiography in chronic thromboembolic pulmonary hypertension

Abstract

Background: Mean pulmonary arterial pressure (MPAP) is an important pulmonary hemodynamic parameter in the management of patients with chronic thromboembolic pulmonary hypertension (CTEPH).We compared echocardiography-derived estimates of MPAP with direct right heart catheterization (RHC) to identify reliable noninvasive methods for estimating MPAP derived RHC (MPAP RHC ) in these patients. Methods and Results: Echocardiography and RHC were sequentially performed in 56 patients with CTEPH (mean age: 60.5 ± 12.0 years; 44 females). We measured the tricuspid regurgitation (TR) pressure gradient (TRPG) using echocardiography. The mean systolic right ventricular (RV)–right atrial (RA) gradient was calculated by tracing the TR time velocity flow. Systolic and mean pulmonary artery pressures (SPAP TR and MPAP TR ) estimated from TRPG and mean systolic RV–RA gradient were calculated by adding RA pressure based on the inferior vena cava. MPAP Chemla was calculated using Chemla9s formula: 0.61 × SPAP TR + 2 mmHg. MPAP RHC and pulmonary vascular resistance were 35.9 ± 11.3 mmHg and 6.6 ± 3.6 Wood units, respectively. The mean difference from MPAP RHC and limits of agreement were −1.5 mmHg and −19.6 to 16.5 mmHg for MPAP TR , and −4.6 mmHg and −24.5 to 15.2 mmHg for MPAP Chemla . Accuracy within 10 mmHg and 5 mmHg of MPAP RHC was 80.4% and 46.4% for MPAP TR , and 71.4% and 48.2% for MPAP Chemla , respectively. Conclusions: MPAP TR and MPAP Chemla are reliable estimates for MPAP RHC in patients with CTEPH.