Analysis of the arterial blood pressure waveform during left ventricular nonpulsatile assistance in animal models

When the rotary blood pump is used as a left ventricular assist device (LVA D), the arterial blood pressure waveform changes with the LVAD condition. B ased on evidence from an in vitro study, the change of the arterial blood p ressure waveform during left ventricular assistance was evaluated using ani mal models. After the left pleural cavity was opened through the fifth inte rcostal space under general anesthesia, a rotary blood pump was implanted a s an LVAD into 6 healthy calves. The direct left carotid arterial blood pre ssure waveform was measured and recorded by an oscilloscope. The Fast Fouri er Transform technique was utilized to analyze the arterial blood pressure waveform and calculate the pulsatility index (PI) and the pulse power index (PPI). Similar to the in vitro study, the PI and PPI decreased exponential ly with the increase of the LVAD assist ratio. By using this analysis metho dology, a physiologically effective ventricular assistance might be achieve d.