CONTINOUS, NONINVASIVE DETERMINATION OF VENTRICULAR PARAMETERS

RECENTLY, A CLINICALLY VALIDATED RELATIONSHIP BETWEEN DETERMINATION OF EJECTION FRACTION CALCULATED FROM (1) NON-INVASIVE MEASUREMENT OF THE SYSTOLIC TIME INTERVALS OF THE ECG AND PHONO-CARDIOGRAPHY OR CAROTID ARTERY TRACING, AND EJECTION FRACTION AS MEASURED BY (2) INVASIVE METHODS, SUCH AS REDIONUCLIDES OR CINE-ANGIOGRAPHY, HAS BEEN ESTABLISHED. THE ON-GOING RESEARCH IN THE FIELD OF ELECTRICAL BIOIMPEDANCE HAS PROVEN CLINICALLY VALID ACCURACY OF NON-INVASIVE MEASUREMENT OF STROKE VOLUME AND NON-INVASIVE MEASUREMENT OF SYSTOLIC TIME INVERVALS FROM MEASUREMENT OF THORACIC ELECTRICAL IMPEDANCE AND ITS CHANGES. IF SUCCESSFUL, THIS PHASE I PROPOSAL WILL PROVE THAT THROUGH INNOVATIVE APPLICATION OF THE RELATIONSHIPS REFERENCED ABOVE, A PRECISE MEASUREMENT OF IN VIVO CARDIAC CHAMBER SIZE AND FUNCTION BECOMES COST FEASIBLE. ADDITIONALLY, PROPOSAL STUDIES WILL SHOW THAT IT IS POSSIBLE, WITHIN CURRENT TECHNOLOGIES, TO DESIGN A RELATIVELY LOW-COST, MICROPROCESSOR-BASED INSTRUMENT WHICH WILL OFFER CONTINUOUS MONITORING OF STROKE VOLUME, EJECTION FRACTION AND END-DIASTOLIC VOLUME NON-INVASIVELY AND FOR EVERY HEART BEAT. SUCH A DEVICE WILL HAVE AN EXTENSIVE POTENTIAL COMMERCIAL AND MILITARY APPLICATION IN MONITORING THE CRITICALLY ILL PATIENTS.