Systolic Time Intervals in the Diagnosis of Heart Failure in Emergency Departement

STIs were measured using simultaneous recording of the electrocardiogram and acoustic cardiography signals using an analogic numeric system (Biopac Systems, Goleta, CA). A3-minute acoustic cardiographic tracing for all patients was obtained and stored electronically. We measured the electromechanical activation time (EMAT) which is the time between the initial deflection of the electrocardiographic Q wave and the first phonocardiographic complex corresponding to the first heart sound (S1). The left ventricle ejection time (LVET) defined as the interval between the peak components from the S1 and S2 complexes was measured on the same cardiac cycles. All studies were performed in patients in a semi-recumbent position with head at 30 degrees position. For each patient, the acoustic cardiographic parameters were calculated from a 10-second free of artifact recording of data averaging 8 to 12 beats measurements.