Automatic non-invasive blood pressure measurement in left ventricular assist device patients with a photoplethysmography assisted device.

INTRODUCTION: Non-invasive measurement of blood pressure in patients with a left ventricular assist device (LVAD) is challenging due to the mechanical properties of these circulatory support devices. Keeping blood pressure in a target range is crucial to reduce the risk of LVAD complications. As current assessment methods require trained personnel resulting in infrequent monitoring, devices for home-based measurements are sorely needed. OBJECTIVES: In this paper, we report a measurement method and a custom-made monitoring device based on photoplethysmography (PPG) enabling automated measurement of the mean arterial pressure (MAP) of patients with LVAD. METHODS: The method and the device were tested on 21 adult patients with LVAD, and the estimated MAP values were compared to MAP values measured simultaneously by a human expert applying the commonly used Doppler-based method. RESULTS: Results of the proposed method showed highly significant correlation with Doppler-based MAP values (R = 0.85 for inflation, p < 0.001; R = 0.96 for deflation, p<0.001). The mean difference of the proposed method to the Doppler-based MAP values was 1.48 ± 5.43 mmHg for inflation and -0.19 ± 2.71 mmHg for deflation. CONCLUSION: The results demonstrate that the proposed method is a promising direction to achieve accurate, automated, non-invasive BP measurement, applicable in home health monitoring for patients with LVAD.