Mechanical Translation of Electrical Abnormalities With a New Electromechanical Model of Human Ventricular Cell

Investigating cardiac electrical abnormalities using computational models of cardiomyocytes is nowadays established. However, less attention has been paid, until recently, on how these abnormalities impact contractility. We here present a novel electromechanical model, developed by introducing a recently published contractile element in our electrical model Bartolucci-Passini-Severi. Our electromechanical model is able to reproduce delayed afterdepolarization, early afterdepolarizations, and contraction abnormalities in terms of aftercontractions triggered by either drug action or specific pacing protocols. Our findings confirm the experimental evidence that both delayed and early afterdepolarizations can trigger aftercontractions. In addition, we hypothesize that there is not a 1:1 afterdepolarizations-aftercontraction correspondence as aftercontractions appeared only in the presence of specific electrophysiology mechanisms. Hence the proposed electromechanical model is suitable to assess drug safety and investigate drug arrhythmic risk not only in terms of electrophysiology but also in contractility.