Prognostic value of an echocardiographic index reflecting right ventricular operating stiffness in patients with heart failure

Purpose We recently reported a noninvasive method for the assessment of right ventricular (RV) operating stiffness that is obtained by dividing the atrial-systolic descent of the pulmonary artery-RV pressure gradient (PRPGD(AC)) derived from the pulmonary regurgitant velocity by the tricuspid annular plane movement during atrial contraction (TAPM(AC)). Here, we investigated whether this parameter of RV operating stiffness, PRPGD(AC)/TAPM(AC), is useful for predicting the prognosis of patients with heart failure (HF). Methods We retrospectively included 127 hospitalized patients with HF who underwent an echocardiographic examination immediately pre-discharge. The PRPGD(AC)/TAPM(AC) was measured in addition to standard echocardiographic parameters. Patients were followed until 2 years post-discharge. The endpoint was the composite of cardiac death, readmission for acute decompensation, and increased diuretic dose due to worsening HF. Results 58 patients (46%) experienced the endpoint during follow-up. Univariable and multivariable Cox regression analyses demonstrated that the PRPGD(AC)/TAPM(AC) was associated with the endpoint. In a Kaplan-Meier analysis, the event rate of the greater PRPGD(AC)/TAPM(AC) group was significantly higher than that of the lesser PRPGD(AC)/TAPM(AC) group. In a sequential Cox analysis for predicting the endpoint's occurrence, the addition of PRPGD(AC)/TAPM(AC) to the model including age, sex, NYHA functional classification, brain natriuretic peptide level, and several echocardiographic parameters including tricuspid annular plane systolic excursion significantly improved the predictive power for prognosis. Conclusion A completely noninvasive index of RV operating stiffness, PRPGD(AC)/TAPM(AC), was useful for predicting prognoses in patients with HF, and it showed an incremental prognostic value over RV systolic function.