Right ventricle free wall longitudinal strain screening of lung transplant candidates

Background: Lung transplant (LUTX) candidates have subclinical right ventricular (RV) dysfunction, which has not yet been assessed by speckle-tracking echocardiography (STE)-derived RV free-wall longitudinal strain (RVFWLS). To evaluate the prevalence of RV dysfunction by RVFWLS and its relationship with conventional RV echocardiographic indexes in LUTX candidates. Methods: In a single-center prospective observational cohort study, from January 2021 to March 2023 consecutive LUTX candidates underwent cardiac catheterization, radionuclide ventriculography, standard and STE. The diagnostic accuracy of RV ejection fraction by ventriculography (RVEF), tricuspid annular plane excursion (TAPSE), fractional area change (FAC), tricuspid peak annulus systolic velocity (S') versus RVFWS were computed. Results: Thirty-four patients (female, 41%) with a mean age of 48 [36-59] years old enlisted for pulmonary fibrosis (35%) and cystic fibrosis (30%) were included. At cardiac catheterization, only 7 (23%) had pulmonary hypertension. Around 15-25% presented right heart enlargement. Tricuspid regurgitation was present in 20 (60%) of the patients. Median RVFWLS was -20.1% [-22.5%--17%], being impaired (> -20%) in 16 (47%) of the patients. RVFWLS identified the highest percentage (47%) of RV dysfunction, compared to TAPSE (32%), S' (27%), FAC (26%), and ventriculography (15%), which had very low sensitivity for detecting RV dysfunction compared to RVFWLS. Conclusions: In patients enlisted for LUTX, RV dysfunction assessed by STE-derived RVFWLS is highly prevalent. STE can detect RV dysfunction better than standard two-dimensional echocardiography and ventriculography. Further studies are urgently needed to define the clinical implications and the prognostic value of RV dysfunction measured with RVFWLS.