(P134) SPECKLE TRACKING RV GLOBAL LONGITUDINAL STRAIN FOR PREDICTION OF PULMONARY HYPERTENSION

Background: Right ventricular (RV) systolic dysfunction in patients with pulmonary hypertension is associated with worsening outcomes. Novel methods such as speckle tracking echocardiography (STE) can provide an assessment of strain and quantitate global and regional myocardial function. The objective of our study was to assess the relationships between commonly used methods of RV function and STE strain, and to further evaluate if strain can be used to risk stratify pulmonary hypertension.

METHODS AND RESULTS: We included consecutive patients who had an echocardiogram performed with primary indication being “pulmonary hypertension” at Vancouver General Hospital between January 2021 and April 2021. Echocardiographic characteristics of the patients in the cohort were extracted from the hospital echo image archiving system, Syngo Dynamics [Siemens Medical Solutions, Ann Arbor, MI]. The extracted data included RV function by visual assessment, TAPSE, tissue Doppler RV S’, fractional area change (FAC), and pulmonary artery systolic pressure (PASP). Visual assessment was reported as either normal or abnormal (mild, moderate, severely reduced RV systolic function). Speckle tracking global RV strain was analyzed in this study by single operator (SB), using TomTec, as a novel assessment of RV function. Correlations between strain and different RV parameters were assessed. Comparison of strain to other RV parameters for prediction of severity of pulmonary hypertension was made. A total of 91 patients were included in our study (78 with nonmissing PASP). There was significant Spearman rank correlation between strain and the following parameters: RVA4C (r=-0.54, p= <.0001), TAPSE (r=0.56, p= <.0001), S’ (r=0.36, p=.0007), FAC (r=0.84. p= <.0001), and PASP (r=-0.63, p= <.0001). In linear regression models, strain predicts TAPSE [B=0.24, 95% C.I. (0.15, 0.32), p<.0001], RVA4C [B=-0.45, 95% C.I. (-0.60, -0.29), p<.0001], and PASP [B=-1.44, 95% C.I. (-1.90, -0.98), p<.0001]. Logistic regression models predicting PASP ³35mmHg, ³50mmHg, and ³70mmHg using strain were statistically significant ([OR= 0.88, 95% C.I. (0.83, 0.94), p=0.0003]; [OR= 0.79, 95% C.I. (0.69, 0.89), p=0.0002); and [OR=0.75, 95% C.I. (0.62, 0.90), p=0.0022]), respectively. FAC alone and strain alone predicts at least moderate (50mmHg+) pulmonary hypertension very well (ROC AUC: FAC 0.898; Strain 0.864; FAC+ Strain 0.900). The use of both FAC and strain provides the best predictive ability, even though this did not reach statistical significance.

Conclusion: Speckle tracking strain assessment of RV global function can discriminate severity of pulmonary hypertension. It correlates well with other RV function parameters and enhances FAC in the prediction of at least moderate pulmonary hypertension.