Digital signal processing for evaluation of the effect of atrial systole on early diastolic intraventricular pressure gradient

The early diastolic intraventricular pressure gradient (EDVPG) was studied in the presence and in the lack of atrial contraction in late diastole. High gain diastolic pressures were digitally recorded with a double sensor micromanometer in the left ventricular (LV) inflow tract in closed chest, atrioventricular (AV) blocked canine preparations during AV sequential pacing. The duration and the area of positive and reversed EDVPG were analyzed and compared by digital signal processing at AV delay of 0 and 150 ms. The duration of positive and reversed EDVPG was similar but the area of the positive and of the reversed EDVPG was larger at AV delay of 0 ms. Thus, the lack of the atrial transport resulted in an increase of the positive and negative EDVPG-time integral