Abstract 16323: Nonlinear Afterload-Dependence of RV Strain: A Follow-Up Study During Pulmonary Vasodilator Therapy
Background: RV function is difficult to quantify with conventional echocardiography and RV free wall strain (RVGS) has been validated for this purpose. However, strain is afterload-dependent, so understanding RV status in pulmonary hypertension is challenging. We studied the relationship between changes in right ventricular systolic pressure (RVSP ) and changes in RVGS.
Methods: Data were gathered prospectively in 100 pts (77% women, age 63±15 y) undergoing routine echo before and during vasodilator therapy of pulmonary hypertension (PHT). LV and RV dimensions and function were assessed per guidelines. RVSP was measured from tricuspid regurgitation maximum pressure gradient and estimated RA pressure. RVGS was obtained in an apical RV view using speckle tracking (Research-Arena, TomTec Imaging Systems, Germany). A subgroup underwent right heart catheterisation (n=17), and 6 minute walk(6MW) test (n=75). Statistical analysis was performed using SPSS (IBM, 20) with significance set to p<.05 .
Results: Using a quadratic linear regression model showed a significant relationship between changes in RVSP and changes in RVGS (r=0.43, p=.02).No relationship could be defined between changes in RVSP and changes in FAC (r=0.16, p=.30).Change in RVSP was associated with 6MW (r=.53, p=.006).Highly significant correlations were found between changes in invasive PASP and echocardiographic RVSP (r=0.8, p<.001).
Conclusions: Changes in RV free strain correlate in a non-linear fashion to changes in RVSP in a pulmonary hypertension cohort. These features need to be kept in mind in the evaluation of RV function using strain.
- © 2013 by American Heart Association, Inc.