The pathological conditions of the patients were reproduced by setting model parameters (see the cardiocirculatory electrical analogue) as reported below:
• in order to obtain the measured systolic (BPS) and diastolic (BPD) systemic arterial pressure, systemic arterial resistance was automatically calculated using a dedicated algorithm implemented in the simulator;
• knowing systemic arterial resistance, BPS, BPD and the timing constant, also systemic arterial compliance was estimated;
• septum systolic (diastolic) elastance was calculated starting from systolic (diastolic) septum thickness measured by ECO;
• left ventricular systolic (diastolic) elastance was set in order to place the left ventricular loop in the pressure-volume plane, knowing the measured ESV, EDV. To place the left ventricular loop it has also been assumed that the left ventricular end systolic pressure can be approximated with mean aortic pressure value;
• heart rate (HR) was set as the measured value;
• from ECG signal, QT, PQ and QRS were measured and then inserted in the model of ECG implemented in the software;
• finally the interventricular and intraventricular delay were set staring from the data measured by ECO.
After viventricular pacemacker (BPM) implantation, the patient conditions were simulated programming the BPM according to the temporizations chosen by physicians.