Cardiac MRI derived ventricular-arterial coupling ratio predicts myocardial energetics in patients with congenital heart disease

Motivation: Ventricular-arterial coupling (VAC) - a ratio of arterial over ventricular elastance (Ea/Ees) - was found to predict clinical outcomes and was associated with myocardial energetics: stroke work (SW), potential energy (PE). Goal(s): To compare invasive-VAC (Ea/Ees) with noninvasive-VAC (ESV/SV) ability to predict ventricular efficiency (i.e. SW/SW+PE). Approach: Biomechanical model of the heart was used to recontract patient-specific pressure-volume (PV) loops from CMR and catheterization data in 30 patients with Fontan circulation, 20 and 16 right and left ventricles of patients with rTOF. VAC and SW/SW+PE were derived from PV loops. Results: Both invasive-VAC and noninvasive-VAC were strong predictors of ventricular efficiency. Impact: Ventricular arterial coupling (arterial (Ea)/ventricular (Ees) elastance) was a strong predictor of ventricular efficiency ratio (SW/SW+PE). CMR-derived VAC (ESV/SV) was equivalent to Ea/Es suggesting the potential of ESV/SV to be an important indicator of cardiovascular energetics.