Inverse allometry: foundations for a bioinspired LVH-prediction model

Abstract

Allometry, in general biology, measures the relative growth of a part in relation to the whole living organism. Left ventricular hypertrophy (LVH) is the heart adaptation to excessive load (systolic or diastolic) that leads to an increase in left ventricular mass, which in turn, raises the electrocardiographic voltages. If this mass increase followed an allometric law, then it would be possible to design a bioinspired model based on the allometric equation to predict LVH. In this work, we first investigated the validity of this hypothesis and then proposed an LVH marker based on the inverse allometry model. Based on clinical data, we compared the allometric behavior of three different ECG markers of LVH. To do this, the allometric fit AECG = δ + β(VM) relating left ventricular mass (estimated from echocardiographic data) and ECG amplitudes (expressed as the Cornell-Voltage, Sokolow and the ECG overall voltage indexes) were compared. Besides, sensitivity and specificity for each index were analyzed. The more sensitive the ECG criteria, the better the allometric fit. Finally, the Receiver Characteristic Curve (ROC) of an allometric model proposed here was computed. In conclusion: The allometric paradigm should be regarded as the way to design new and more sensitive ECG-based LVH markers.