Myocardial work during various right ventricle load conditions in a paediatric population

Assessing right ventricular (RV) function in children is challenging, particularly in RV overload, where conventional echocardiographic indices do not account for afterload.

This prospective single-centre study evaluated the feasibility and utility of RV myocardial work (MW), which integrates strain and afterload, in children with different RV loading conditions.

The study included children with volume overload (pre-tricuspid shunts) or pressure overload (precapillary pulmonary hypertension) and healthy controls. All underwent two- and three-dimensional echocardiography to assess RV volumes and strain, and derive RV MW from the pressure-strain relationship.

RV MW indices (median [minimum-maximum; interquartile range]) were higher in pressure overload (n=17) versus volume overload (n=18) versus controls (n=17): RV global work index (740 [479-1624; 311] vs 445 [368-676; 92] vs 361 [242-485; 108] mmHg%; all P<0.05); RV global constructive work (854 [708-2208; 588] vs 564 [467-754; 103] vs 468 [281-594; 122] mmHg%; all P<0.05) and RV global wasted work (69 [19-282; 147] vs 29 [9-54; 13] vs 20 [5-44; 15] mmHg%; P<0.05 for pressure overload vs volume overload and controls). Global work efficiency did not differ significantly between groups. Tricuspid annular plane systolic excursion divided by systolic pulmonary artery pressure showed strong inverse correlations with RV global work index (ρ=-0.83; P<0.0001) and RV global constructive work (ρ=-0.88; P<0.0001), a moderate correlation with global wasted work (ρ=-0.57; P<0.0001) and a weak, non-significant correlation with global work efficiency (ρ=0.26; P=0.0578).

RV MW assessment is feasible in children and reveals functional alterations not detected by conventional indices, particularly in the context of pressure overload, highlighting its potential as an advanced tool for evaluating RV function in paediatric RV overload.