Right ventricular myocardial work: proof-of-concept for non-invasive assessment of right ventricular function

Abstract

Aims: Right ventricular myocardial work (RVMW) is a novel method for non-invasive assessment of right ventricular (RV) function utilizing RV pressure-strain loops. This study aimed to explore the relationship between RVMW and invasive indices of right heart catheterization (RHC) in a cohort of patients with heart failure with reduced left ventricular ejection fraction (HFrEF), and to compare values of RVMW with those of a group of patients without cardiovascular disease.

Methods and results: Non-invasive analysis of RVMW was performed in 22 HFrEF patients [median age 63 (59-67) years] who underwent echocardiography and invasive RHC within 48 h. Conventional RV functional measurements, RV global constructive work (RVGCW), RV global work index (RVGWI), RV global wasted work (RVGWW), and RV global work efficiency (RVGWE) were analysed and compared with invasively measured stroke volume and stroke volume index. Non-invasive analysis of RVMW was also performed in 22 patients without cardiovascular disease to allow for comparison between groups. None of the conventional echocardiographic parameters of RV systolic function were significantly correlated with stroke volume or stroke volume index. In contrast, one of the novel indices derived non-invasively by pressure-strain loops, RVGCW, demonstrated a moderate correlation with invasively measured stroke volume and stroke volume index (r = 0.63, P = 0.002 and r = 0.59, P = 0.004, respectively). RVGWI, RVGCW, and RVGWE were significantly lower in patients with HFrEF compared to a healthy cohort, while values of RVGWW were significantly higher.

Conclusion: RVGCW is a novel parameter that provides an integrative analysis of RV systolic function and correlates more closely with invasively measured stroke volume and stroke volume index than other standard echocardiographic parameters.

Keywords: cardiac index; heart failure with reduced ejection fraction; non-invasive myocardial work; right ventricle; stroke volume.