Deformation pattern and predictive value of right ventricular longitudinal strain in children with pulmonary arterial hypertension

BACKGROUND: Right ventricular function has been identified as an important prognostic factor in children with pulmonary arterial hypertension. The aim of the study was to assess the deformation pattern and prognostic value of right ventricular longitudinal strain in children with pulmonary arterial hypertension. METHODS: We prospectively evaluated 46 children (25 with pulmonary arterial hyperetension and 21 age and sex matched controls) using conventional and speckle-tracking echocardiography, brain natriuretic peptide levels and clinical status expressed by WHO functional class and 6-min walking test. According to the clinical status after 12 months of follow-up, the pulmonary arterial hypertension patients were divided in two groups: non-worsening (13) and worsening (12). RESULTS: Right ventricular free wall longitudinal strain and strain rate were significantly lower in children with PAH compared with controls (−24.72 ± 3.48 vs −15.60 ± 3.40, p = 0.0001 and −1.44 ± 0.09 vs −1.09 ± 0.15, p = 0.0001, respectively). There was a more expressed decrease of basal than apical region of right ventricular free wall longitudinal strain/strain rate in pulmonary arterial hypertension patients compared with controls (strain: p = 0.0001 vs p = 0.07 and strain rate: p = 0.0001 vs p = 0.002). Comparing worsening and non-worsening pulmonary arterial hypertension patients there was a significant difference in Mid right ventricular free wall longitudinal strain (−14.00 ± 3.13 vs. −20.76 ± 4.62, p = 0.0001). In multivariable logistic regression analysis Mid right ventricular free wall longitudinal strain was an independent predictor of worsening in pulmonary arterial hypertension children (OR 0.45; 95 % CI: 0.21–0.96, p = 0.041). In ROC curve analysis a cut-off value of Mid right ventricular free wall longitudinal strain of −18.50 % predicted clinical worsening in pulmonary arterial hypertension children, with a sensitivity and specificity of 91.7 and 30.8 %, respectively (area under curve = 0.88 ± 0.06, 95 % CI: 0.75–1.00, p = 0.001). CONCLUSIONS: Two-dimensional speckle-tracking echocardiography is a complementary non-invasive tool for assessment of right ventricular function in children with severe pulmonary arterial hypertension, allowing also clinical prediction and segmental analysis of right ventricular myocardial performance in these patients.