Aims: Right ventricular (RV) mass and volume calculations are important correlates of survival in patients with pulmonary arterial hypertension (PAH). We tested the hypothesis that RV mass, volumes and function could be measured accurately with real-time three-dimensional echocardiography (3DE) in patients with PAH and compared those against cardiac magnetic resonance (CMR).
Methods and results: Sixty consecutive PAH patients and 20 normals were examined with 3DE and CMR. RV end-diastolic volumes (EDV), end-systolic (ESV), stroke volume (SV), ejection fraction (EF), and mass were measured in all patients and in normals. Two independent observers assessed variability using the Bland-Altman analysis agreement. RV volumes (in mL) and mass were similar between 3DE and CMR in PAH patients: [EDV (in mL) 183.2 +/- 38 vs. 187.3 +/- 41, P = 0.32; ESV (in mL) 122 +/- 33 vs. 126 +/- 36, P = 0.99; SV (in mL) 63 +/- 15 vs. 65 +/- 19, P = 0.06; EF (in %) 33 +/- 7 vs. 31 +/- 9, P = 0.16 and RV mass (g) 99 +/- 20 vs. 96 +/- 22, P = 0.42], respectively. Interobserver variability was similar between 3DE and CMR in PAH for all variables, with CMR showing less interobserver variability for EDV compared with 3DE in both patients and normals (patients: mean bias: CMR-EDV: 0.4 +/- 16 mL vs. 3DE-EDV: 6.9 +/- 17.9 and in normals: CMR-EDV: 0.1 +/- 9.8 vs. 3DE-EDV: 5.7 +/- 16.3, respectively), whereas EF and RV mass were poorly reproducible with no correlation between observers for 3DE and CMR.
Conclusions: RV remodelling in PAH patients can be accurately assessed with both 3DE and CMR. Both modalities are robust and reproducible with CMR being more reproducible for measurements of EF and RV mass.