AbstractEvaluating right ventricular (RV) function remains a challenge. Recently, novel echocardiographic assessment of RV myocardial work (RVMW) by non-invasive pressure-strain loops was proposed. This enables evaluation of right ventriculoarterial coupling and quantifies RV dyssynchrony and post-systolic shortening. We aimed to assess RVMW in patients with different etiologies of RV dysfunction and healthy controls. We investigated healthy controls (n=17), patients with severe functional tricuspid regurgitation (FTR; n=22), and patients with precapillary pulmonary hypertension (PCPH; n=20). Echocardiography and right heart catheterization were performed to assess 1) RV global constructive work (RVGCW; work needed for systolic myocardial shortening and isovolumic relaxation), 2) RV global wasted work (RVGWW; myocardial shortening following pulmonic valve closure), and 3) RV global work efficiency (RVGWE; describes the relation between RV constructive and wasted work). RVGCW correlated with invasive RV stroke work index (r=0.66, P<0.001) and increased in tandem with higher afterload, i.e., was low in healthy controls (454±73 mmHg%), moderate in patients with FTR (687±203 mmHg%), and highest among patients with PCPH (881±255 mmHg%). RVGWE was lower and RVGWW was higher in patients with FTR (86±8% and 91 mmHg% [53-140]) or PCPH (86±10% and 110 mmHg% [66-159]) as compared with healthy controls (96±3% and 10 mmHg%). RVMW by echocardiography provides a promising index of RV function to discriminate between patients with RV volume or pressure overload. The prognostic value of this measure needs to be settled in future studies. Graphical abstract Combining right heart catheterization and echocardiography, right ventricular (RV) pressure-strain loops were evaluated in healthy controls and in patients with severe functional tricuspid regurgitation (FTR) or precapillary pulmonary hypertension (PCPH). RV global constructive work (RVGCW) entails the work needed for systolic myocardial shortening and isovolumic relaxation; it increased in tandem with higher afterload. RV global wasted work (RVGWW) describes myocardial shortening following pulmonic valve closure and RV global work efficiency (RVGWE) is the ratio between RVGCW and RVGWW. RVGWW was higher and RVGWE was lower in both patient groups with RV hemodynamic overload.