Mean Pulmonary Artery Pressure Using Echocardiography in Chronic Thromboembolic Pulmonary Hypertension

Abstract

Background:Mean pulmonary arterial pressure (MPAP) is an important pulmonary hemodynamic parameter used in the management of patients with chronic thromboembolic pulmonary hypertension (CTEPH). We compared echocardiography-derived estimates of MPAP with right heart catheterization (RHC) to identify reliable noninvasive methods of estimating MPAP-derived RHC (MPAP_RHC) in these patients.Methods and Results:Echocardiography and RHC were performed in 56 patients with CTEPH (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_TRand MPAP_TR) estimated from TRPG and mean systolic RV-RA gradient were calculated by adding RA pressure based on the inferior vena cava. MPAP_Chemlawas calculated using Chemla’s formula: 0.61×SPAP_TR+2 mmHg. MPAP_RHCand pulmonary vascular resistance were 35.9±11.3 mmHg and 6.6±3.6 Wood units, respectively. The mean difference from MPAP_RHCand 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_RHCwas 80.4% and 46.4% for MPAP_TR, and 71.4% and 48.2% for MPAP_Chemla, respectively.Conclusions:MPAP_TRand MPAP_Chemlaare reliable estimates for MPAP_RHCin patients with CTEPH.