3D regional right ventricular function in pulmonary hypertension
Résumé
Purpose: Pulmonary hypertension (PH) is a rare and severe disease for which right ventricular (RV) remodelling and function are associated with survival. The unique anatomy and structure of the RV limit 2D analysis, and its regional function has not been studied yet. We show the contribution of regional 3D deformation analysis for the study of RV remodelling in patients with PH, as compared to healthy controls.
Methods: 3D RV echocardiographic sequences were prospectively obtained from 32 patients with PH (57±21y, 15 male) and 10 healthy controls (38±13y, 6 male). Myocardial tracking was performed by semi-automatic Tomtec 4D RV-Function 2.0 software. Volumes and EF were directly obtained from the software. Output RV meshes were post-processed to extract local deformation (area strain) and radial/circumferential/longitudinal displacement. Data were temporally realigned to allow inter-subject pattern comparison. Spatial correspondences were obtained from the software, and allowed statistical computation in 8 standard zones of the RV.
Results: 19 patients (59%) were NYHA class III-IV at baseline. Over a mean FU of 49±41days, 5 patients died from cardiopulmonary causes. The highest contraction was at the RV lateral and inferior levels. Regional motion and deformation and global volume patterns for patients was significantly affected at the RV anterior, lateral, inferior, and trabecular and inlet septum. The first 4 segments were significantly associated with NYHA class and survival. Global area strain >-15% was a significant predictor of death (HR 411e12 [140 – 1.2e27]).
Conclusion: Our study confirms that the segments into which RV contraction predominates are also the determinants of symptoms and survival in PH patients. This is of high relevance to establish the prognosis of such patients.