抄録
In a purpose to evaluate the effects of left atrium to aorta (LA-Ao) bypass, pressure-volume curves obtained by UCG and manometry, were analyzed. Bypass system was composed of roller pump and pulsatile assist device inserted between aorta and roller pump. Eight mongrel dogs weighing 17 to 21Kg were used in this study. Pressure-volume curves were drawn according to the changes in bypass flow of every 25ml/Kg/min. Decreases in left ventricular net work and left ventricular output (PA flowbypass flow), according to the increases in bypass flow of every 25ml/Kg/min were 18% of control. Left ventricular pressure (LVP) was maintained despite increase in bypass flow till 100ml/Kg/min. Decrease in LVP was observed finally when bypass flow increased to 125ml/Kg/min. In this condition left atrial pressure decreased to -10 to -15mmHg simultaneously and maintenance of LA-Ao bypass became difficult because of arrhythmias. From this study, it was concluded that decrease in LV net work can be achieved adequately by LA-Ao bypass and effects of left heart bypass could be evaluated quantitatively by this method.
