Abstract 4365980: Real-World analysis of systemic vascular resistance using a cuffless photoplethysmography-based device for 24-hours ambulatory blood pressure monitoring across diverse patient groups

Introduction: Photoplethysmography-based (PPG) devices represent a significant advancement in noninvasive cardiovascular monitoring. These cuffless technologies enable assessment of hemodynamic parameters with improved comfort, usability and compliance. Modern PPG systems have expanded their capabilities to include advanced metrics such as systemic vascular resistance (SVR) and cardiac output (CO). Many antihypertensive drugs lower blood pressure by reducing SVR through vasodilatation of the systemic and renal vasculature. Limited data is available on SVR during ambulatory monitoring. PPG devices become more common as they allow us to assess SVR in real life, in ambulatory blood pressure monitoring (ABPM) patients. Aim: To evaluate and compare SVR using the Biobeat (WP613) device across patient groups. Methods: Adults from the Hypertension Clinic at University of Miami, Florida, from Aug. 2023–Jan. 2025 underwent 24-h ABPM monitoring using Biobeat device. Patient data was matched with Biobeat. PPG data was available every 15 minutes; The raw data included SBP and DBP, the heart rate, stroke volume, CO and SVR. Results: A total of 539 patients underwent PPG ABPM during the study period. The median was 62 (IQR 54, 71) years, with 57% females (Tab 1) . Patients were defined as hypertensive per AHA 2017 guidelines [SBP≥130 and DBP≥80 mmHg]. Overall, 265 patients were classified as having normal BP, 95 as having isolated systolic hypertension, and 179 as having mixed hypertension. Within the Mix-HTN group, 42 patients had isolated diastolic hypertension and the remaining 137 systolic and diastolic hypertension (Fig 2) . In subgroup analysis (Fig 3); SVR was significantly different between the groups: lowerst in No/C-HTN and highest in Mix-HTN. particularly among the mixed-hypertension group, SVR was higher in the Systolic and Diastolic HTN compared to the Isolated diastolic HTN group. Among the No/C-HTN group, 60 patients were not hypertensives and 205, were hypertensives on at least 1 drug. The SVR was not statistically significant between these 2 subgroups, suggesting that SVR may be a helpful target biomarker used to up-titrate antihypertensives. Conclusion: PPG devices offer a valuable enhancement to conventional ABPM by providing additional physiological measurements such as SVR that can help differentiate between various hypertension phenotypes and potentially provide personalized therapy that target the driver of hypertension.