OBJECTIVES: Cuffless blood pressure (BP) monitors represent an innovative approach to BP assessment, overcoming the traditional episodic nature of readings obtained from cuff-based, oscillometric modalities. Nonetheless, the comparison of these cuffless devices against their cuff-based counterparts remain debated. METHODS: This study evaluated BP readings from a cuffless, continual BP monitor (Aktiia monitor, Neuchâtel, Switzerland) and a standard 24-h ambulatory BP monitor (ABPM
Dyasis 3, Novacor, Paris, France) in 54 patients undergoing a 12-week cardiac rehabilitation program in Neuchâtel, Switzerland. Comparisons encompassed 24-h, daytime (9 a.m.-9 p.m.), and night-time (11 p.m.-7 a.m.) systolic and diastolic BP (SBP, DBP) using a 7-day average from Aktiia overlapping a 1-day average from ABPM. Nocturnal dip analysis was performed with 1-day average from Aktiia coinciding with ABPM measurements. RESULTS: No significant differences emerged between the Aktiia and ABPM monitors for 24-h and daytime SBP (24-h: 2.6 ± 12.3 [-0.2, 5.4] mmHg, r = 0.57, P = 0.06
daytime: 1.2 ± 12.4 [-1.6, 4.0] mmHg, r = 0.60, P = 0.38). Night-time SBP showed more evident differences (12.5 ± 14.4 [9.3, 15.8] mmHg, r = 0.39, P <
0.002). DBP were within clinical range across 24-h and daytime (24-h: -2.9 ± 7.9 [-4.7, -1.1] mmHg, r = 0.63, P = 0.002
daytime: -3.1 ± 8.2 [-5.0, -1.3] mmHg, r = 0.64, P = 0.002), and showed significant differences for night-time (4.1 ± 8.5 [2.2, 6.0] mmHg, r = 0.57, P <
0.002). The concordance rate with ABPM's nocturnal dip was 79% for 1-day average from Aktiia. CONCLUSIONS: These results demonstrate that the Aktiia monitor yields BP measurements consistent with an ABPM monitor despite some systematic differences during night-time readings. The Aktiia monitor holds potential for future use in continual BP monitoring. CLINICAL TRIAL REGISTRATION: NCT04548986. URL: https://clinicaltrials.gov/study/NCT04548986?tab=results.