Mapping and monitoring of cardioactivity: Multi-channel impedance technology and system

Abstract

Theoretical modeling and experimental studies were conducted to investigate a mechanism of the precordial bioimpedance signal conditioning. Prototype models of an electrode system and a new multi-channel non-invasive measuring system with a necessary sensitivity, a penetration depth, and a spatial and time resolutions were designed and experimentally studied. The 32-channel rheographic system developed allows registration of the electrocardiogram (ECG) and the transthoracic rheogram (TTRG) simultaneousely with up to thirty precordial rheocardiograms (PreRCG). The results of the conducted research and the tests of the prototype of the functioning device demonstrated that a method of the impedance precordial mapping, the proposed multi-channel system and technology are highly perspective for solving the following tasks of medical diagnoctics: localization of the heart, aorta, and pulmonary trunk in the thoracic cavity; determination of the heart anatomical long axis orientation; localization and evaluation of the size of main structural components of the heart such as atria, ventricles, heart boundaries, apex, and valves; estimation of the phases of the heart cycle; analysis of dynamics, synchronism, and a sequence of contractions of the atria and ventricles; determination and monitoring of the parameters of the heart pump-function, for instance, stroke volume; functioning and pathologies of the heart valves; monitoring of the variability of parameters which characterize the human heart biomechanics; analysis of the cardio- respiratory relationship. © Springer-Verlag 2007.