In order to meet physiologic changes in LVAD patients, VAD manufacturers have been developing automatic control algorithms for rotary blood pumps. However, whether an automatic control algorithm is required for normal physiological functioning is unknown. Physiological patterns may be monitored by analyzing daily VAD parameter data (Speed, Power, and Estimated Flow) as acquired by the HeartWare® LVAS Controller. Experiment: Log files from patients supported on the HeartWare® LVAS which contained VAD parameter data (logged at 15minute intervals) were analyzed for daily performance under various physiological conditions while a constant VAD Speed was maintained. A 12-point moving average of Estimated Flow was calculated to eliminate erratic deviation in flow and provide a visual reference of circadian rhythm. Resulting data was analyzed and presented in a weekly viewable time frame.
O'Driscoll, G., Tamez, D., & Voskoboynikov, N. (2008). Is an automatic control algorithm necessary for centrifugal pumps? Journal of Cardiac Failure, 14(6), S53. doi:10.1016/j.cardfail.2008.06.167
O'Driscoll, G., Tamez, D., & Voskoboynikov, N. (2008). Is an automatic control algorithm necessary for centrifugal pumps? Paper presented at the 12th Annual Scientific meeting of the Heart Failure Society of America. Toronto, Canada, 21-24 September, 2008.