Right Heart End-Systolic Remodeling Index Strongly Predicts Outcomes in Pulmonary Arterial Hypertension

Abstract

Background Right ventricular (RV) end-systolic dimensions provide information on both size and function. We investigated whether an internally scaled index of end-systolic dimension is incremental to well-validated prognostic scores in pulmonary arterial hypertension (PAH). Methods and Results From 2005 to 2014, 228 patients with PAH were prospectively enrolled. RV end-systolic remodeling index (RVESRI) was defined by lateral length divided by septal height. The incremental values of RV free-wall longitudinal strain (RVLS) and RVESRI to risk scores were determined. Mean age was 49±14 years, 78% were female, 33% had connective tissue disease, 52% were in NYHA class ≥III and mean pulmonary vascular resistance was 11.2±6.4 Wood Units. RVESRI and right atrial area were strongly connected to the other right heart metrics. Three zones of adaptation (adapted, maladapted and severely maladapted) were identified based on the RVESRI to RV systolic pressure relationship. During a mean follow-up of 3.9±2.4 years, the primary endpoint of death, transplant or admission for heart failure was reached in 88 patients. RVESRI was incremental to risk prediction scores in PAH including the REVEAL score, the pulmonary hypertension connection equation and the Mayo clinic model. Using multivariable analysis, NYHA class III/IV, RVESRI, and log N-terminal–pro brain natriuretic peptide (NT-proBNP) were retained (Chi-square 62.2, p<0.0001). Changes in RVESRI at 1 year (n=203) were predictive of outcome; patients initiated on prostanoid therapy showed the greatest improvement in RVESRI. Among right heart metrics, RVESRI demonstrated the best test-retest characteristics. Conclusions RVESRI is a simple reproducible prognostic marker in patients with PAH.

State-of-the-Art Review: Echocardiography in Pulmonary Hypertension

“…An index between 1.35 and 1.70 suggests adverse remodelling. An index !1.7 suggests severe adverse remodelling in the setting of pulmonary hypertension [26].…”

“…Higher Tei index [43], greater right atrial area [24], larger inferior vena cava (IVC) diameter [44], lower TAPSE [44,45], higher estimated mean and diastolic pulmonary artery pressure [44], the degree of interventricular septal shift [44], right ventricular diameters [46], biventricular index [11] and right ventricular end-systolic remodelling ratio [26] have all been reported to be associated with adverse clinical outcomes in the setting of pulmonary hypertension. Right ventricular systolic to diastolic duration ratio is associated with poor outcome in paediatric pulmonary hypertension [21] and Eisenmenger's syndrome [22] but has not been studied in broader pulmonary hypertension settings.…”

Multimodality Imaging of the Right Ventricle

“…Lastly prior studies have demonstrated RV size and function to be a critical prognostic indicator in pulmonary arterial hypertension (PAH) and congenital heart disease. 7,8,9,10 Despite the role of the RV in stratification of prognosis, non-invasive evaluation of the RV remains challenging due to several key anatomic factors.…”

Respite for 2-Dimensional Right Ventricular Imaging?

“…8 Threedimensional echocardiography and speckle tracking imaging have been shown to predict RV failure and clinical outcome more accurately than 2D echocardiography in chronic pulmonary hypertension. 5,7 In this issue of Circulation: Cardiovascular Imaging, Amsallem et al 9 propose a new 2D echocardiography-derived RV end-systolic remodeling index (RVESRI) in patients with pulmonary arterial hypertension (PAH). Amsallem et al define the new RVESRI as the ratio of end-systolic RV lateral wall length to end-systolic septal height measured in the RV-focused apical 4-chamber view.…”