Single-Beat Approach Estimates Preload Recruitable Stroke Work Relationship in PAH

A single-beat estimation of preload recruitable stroke work (PRSW) and its coupling with pulmonary arterial (PA) load in pulmonary arterial hypertension (PAH) provided high accuracy for evaluating right ventricular (RV) contractility and RV adaptation to increased pressure overload, according to a study published in the Journal of the American Heart Association.

A total of 31 consecutive patients with PAH who underwent pressure-volume evaluation during right-sided heart catheterization to diagnose or manage pulmonary hypertension were studied retrospectively.

The investigators developed a novel single-beat slope of the PRSW relationship (M_sw) by using the mean ejection pressure when the end-systolic volume equated the volume-axis intercept of the PRSW relationship. Investigators also developed an index for ventriculoarterial coupling. The study aimed to determine whether the single-beat estimation of the RV M_SW was feasible in these patients.

Of the patients in whom the RV pressure-volume relationship was measured, a total of 23 had PH. The single-beat M_SW estimation of the PRSW slope significantly correlated with the multiple-beat M_SW estimation of the PRSW slope (r=0.91; P <.0001). A strong correlation was also observed between single- and multiple-beat M_SW/mean ejection pressure (r=0.53; P =.002). There was a significantly stronger correlation in patients with greater RV systolic pressures (r=0.70; P =.003).

The retrospective design as well as the relatively small number of participants represent 2 primary limitations of the analysis.

The use of a single-beat approach for estimating M_SW may “help in precisely assessing RV adaptation to increased pressure overload and thereby help improve the management of patients with PH.”

Reference

Inuzuka R, Hsu S, Tedford RJ, Senzaki H. Single-beat estimation of right ventricular contractility and its coupling to pulmonary arterial load in patients with pulmonary hypertension. J Am Heart Assoc. 2018;7:e007929.