Right Ventricular Myocardial Work Predicts Pulmonary Capillary Wedge Pressure Rise During Exercise in Heart Failure

Abstract

Background: Symptoms of heart failure with preserved ejection fraction (HFpEF) are closely related to exercise-induced elevation in pulmonary capillary wedge pressure (PCWP). However, the diagnostic role of right ventricular (RV) myocardial work in HFpEF remains unclear.

Objectives: The purpose of this study was to evaluate the diagnostic utility of RV myocardial work in HFpEF and their correlation with PCWP during exercise.

Methods: Patients with unexplained dyspnea underwent invasive cardiopulmonary exercise tests to identify HFpEF. Echocardiography assessed left and right ventricular parameters. RV myocardial work was calculated using strain rate and pressure curves, matched with electrocardiography data. RV global constructive work, RV global work index, RV global wasted work (RVGWW), and RV global work efficiency (RVGWE) were analyzed.

Results: Forty-one patients with adequate data were enrolled, with 21 diagnosed with HFpEF. No significant differences in various echocardiographic parameters were found between HFpEF and non-HFpEF groups, except higher postexercise PCWP and mean pulmonary artery pressure in HFpEF patients. HFpEF patients had higher RVGWW and lower RVGWE. RVGWW and RVGWE demonstrated superior diagnostic performance for HFpEF compared to other echocardiographic parameters, with areas under the receiver operating characteristic curve of 0.85 (95% CI: 0.73-0.97) and 0.83 (95% CI: 0.70-0.96), respectively. RV global constructive work (r = 0.504; P = 0.001) and RVGWW (r = 0.621; P < 0.001) correlated with postexercise ΔPCWP and exercise PCWP, with RVGWW independently associated with both after adjustment for confounding factors.

Conclusions: RVGWW is a novel predictive parameter that provides a better explanation of RV performance regarding postexercise ΔPCWP than other standard echocardiographic parameters in HFpEF.

Keywords: HFpEF; RV global wasted work; RV myocardial work; ΔPCWP.

Graphical abstract

Figure 1

Method of Semi-Invasive Myocardial Work Analysis Right ventricular (RV) strain curves (red) and RV strain rate curves (blue) are exported from dedicated software. RV pressure recordings obtained via a Swan-Ganz catheter, along with ECG signals, are averaged to create a single cardiac cycle RV pressure curve (from ECG R-wave to R-wave). Both the strain rate and RV pressure curves are resampled and then multiplied to generate the RV power curve. The positive area under the RV power curve represents constructive work (green), while the negative area represents wasted work (brown). ECG = electrocardiography.

Figure 2

Right Ventricular Myocardial Work Analysis Curves of RV pressure (yellow), RV strain (red), inversed RV strain rate (blue), and RV power (black) are plotted together for a heart failure with preserved ejection fraction (HFpEF) patient (right) and a non-HFpEF patient (left). Peak pressure and peak RV shortening are delayed and the RV wasted work (the negative area of the RV power curve) is more in the HFpEF patient. RV = right ventricular; GCW = global constructive work; GWE = global work efficiency; GWW = global waste work.

Figure 3

Correlation of RV Global Wasted Work (RVGWW) With Invasive Hemodynamic Parameters Scatter plots illustrate the correlation between RVGWW and (A) resting pulmonary capillary wedge pressure (PCWP), (B) postexercise change in PCWP (ΔPCWP), (C) stroke volume index, and (D) cardiac index. Significant positive correlations are observed in panels A and B, while no significant associations are found in C and D. Each plot displays the linear regression line with shaded 95% CIs (dashed lines).

Central Illustration

Right Ventricular Myocardial Work in Heart Failure With Preserved Ejection Fraction Right ventricle global waste work (RVGWW) is significantly increased in HFpEF patients and correlated with the change of PCWP at peak exercise. HFpEF = heart failure with preserved ejection fraction; iCPET = invasive cardiopulmonary exercise test; NTUH = national Taiwan university hospital; PCWP = pulmonary capillary wedge pressure; other abbreviation as in Figure 2.