Right ventricular strain to systolic pulmonary artery pressure ratio in response to treatment of pulmonary arterial hypertension

The primary determinant of clinical outcomes in pulmonary arterial hypertension (PAH) is the function of the right ventricle (RV), and regular evaluation for RV dysfunction is increasingly recognized as a risk assessment tool 1. Reducing RV afterload through targeted therapy in PAH is associated with improved RV function and clinical outcome 2. Most commonly, transthoracic echocardiography is conducted to evaluate RV structure and function in clinical practice, both at time of diagnosis and during follow-up. Next to echocardiographic measurements of area and volumes of the RV, the ratio of tricuspid annular plane excursion (TAPSE) to pulmonary artery systolic pressure (PASP) was introduced as a prognostic and treatment-sensitive marker in current guidelines, reflecting the coupling between the RV and the pulmonary artery (PA) 1. However, the use of TAPSE has limitations due to its angle dependency and susceptibility to global heart motion 3. Advances in echocardiographic application provide novel automated measurement tools including RV strain analysis, which is independent of angulation and captures RV segments differentially. The RV free wall longitudinal strain (RVFWLS) specifically measures the longitudinal deformation of the free wall. Recently, Ünlü et al . have replaced TAPSE with RVFWLS and reported on the superior prognostic value of the RVFWLS/PASP ratio in 65 patients with precapillary pulmonary hypertension, with 52% classified as PAH 4. Footnotes This manuscript has recently been accepted for publication in the ERJ Open Research . It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJOR online. Please open or download the PDF to view this article.