Abstract P187: Testing Of A Long-term Implantable Blood Pressure Waveform Monitoring System

Abstract

The long-term Implantable Blood Pressure Waveform Monitoring System consists of a miniature applanation tonometer sensor head connected to a battery powered electronics module via a flexible lead. The BP Sensor continuously monitors the arterial BP waveform with data transmitted to a smart phone for real-time data analysis and display. Key data can be transmitted via the cellular network to a central monitoring station for advanced analysis by a computer and clinician. The BP Sensor has been evaluated for safety, accuracy, stability, and reliability for up to 10 months surrounding the external carotid arteries of large canine. Serial ultrasound studies of the artery-sensor interface shows normal artery shape, diameter, and blood flow velocity. BP Sensor performance remained stable for ~ 60 days between calibrations and correlated with reference BP waveform measurement (± 2.5 mm Hg). The BP Sensor head has a novel design that securely couples the diaphragm to the outside wall of a peripheral artery in optimal alignment with minimal flattening (~ 15 %). The Figure below shows the BP Sensor output signal’s detailed BP waveform four months after implantation. The waveform shows subtle and consistent fluctuations in the peaks and valleys of the BP waveform due to positive pressure mechanical ventilation with a respiratory rate of 14 breaths per minute. This is a significant observation which indicates that the BP Sensor has very good sensitivity (± 1 mm Hg) in the normal hemodynamic range (reference BP ~100/60). The real-time and recorded BP Sensor waveform data will be used to make a diagnosis and adjust medication in a more timely and effective manor, leading to improved clinical outcomes.