Prognostic value of right ventricular-pulmonary arterial coupling in adults with repaired coarctation of aorta

Background: Right ventricular (RV) systolic dysfunction and pulmonary hypertension is present in 20 % of adults with repaired coarctation of aorta (COA). However, the prognostic value of RV to pulmonary artery (RV-PA) coupling in this population is unknown. The purpose of this study was to assess the relationship between RV-PA coupling and clinical outcomes (heart failure hospitalization and all-cause mortality) in this population. Methods: Retrospective cohort study of adults with repaired COA and normal RV systolic function defined as RV free wall strain >= -24 %. RV-PA coupling was assessed using tricuspid annular plane systolic excursion/RV systolic pressure (TAPSE/RVSP) ratio. Results: Of 509 patients (median age 32 [20-45] years; men 290 [57 %]), the average TAPSE and RVSP were 22 +/- 5 mm and 33 +/- 9 mmHg, respectively, and TAPSE/RVSP ratio was 0.78 (0.56-0.96) mm/mmHg. Of 509 patients, 51 (10 %) died and 43 (8 %) were hospitalized for heart failure during a median follow-up of 8.5 (4.9-10.4) years. TAPSE/RVSP was associated with all-cause mortality (hazard ratio 0.82, 95 % confidence interval 0.78-0.86, per 0.1 mm/mmHg), and heart failure hospitalization (hazard ratio 0.86, 95 % confidence interval 0.79-0.93, per 0.1 mm/mmHg) after adjustment for anatomic lesions, cardiovascular interventions, comorbidities, and echocardiographic indices. The inclusion of TAPSE/RVSP ratio in the risk models improved prognostic power of the models to predict all-cause mortality (C-statistics difference 0.046, p < 0.001), and heart failure hospitalization (C-statistics difference 0.031, p = 0.007). Conclusions: TAPSE/RVSP ratio was associated with outcomes in COA patients with normal RV systolic function, suggesting that abnormal RV-PA coupling may be present prior to the onset of overt RV systolic function in this population.