Long-term efficacy and safety of first- and second-generation baroreflex activation devices in refractory...

Baroreflex activation therapy (BAT) has emerged as a device-based therapy for resistant hypertension. Comparative evidence between first-generation (Rheos^®) and second-generation (Barostim Neo^™) BAT systems remains limited.

We retrospectively analysed all patients who underwent BAT implantation between 2006 and 2015 (n = 54) at our centre. The primary outcome was the change in 24h ambulatory blood pressure monitoring (ABPM) between device generations. Secondary outcomes included adverse events, major adverse cardiovascular events (MACE), kidney function, and device-related complications. Office blood pressure, 24h ABPM, and heart rate (HR) were assessed at baseline and during follow-up. Patients with insufficient 24h ABPM follow-up data were excluded from the primary endpoint analysis.

In patients with ABPM data (n = 33), BAT significantly reduced 24h diastolic blood pressure (DBP), 24h systolic blood pressure (SBP), and HR (all p < 0.05). Daytime SBP, DBP, and HR decreased significantly. At night, SBP declined from 165 to 151 mmHg (p = 0.004) and DBP from 98 to 88 mmHg (p = 0.003), while HR remained unchanged. Rheos^® was associated with significant reductions in 24h and night-time SBP; daytime SBP decreased numerically but did not reach statistical significance. Barostim Neo^™ (n = 14) reduced 24h and daytime HR (p = 0.006 and p = 0.009) but showed no statistically significant BP reduction. No significant differences were observed between devices in complication rates, kidney function, or MACE.

Baroreflex activation was safe and associated with reductions in 24h blood pressure and heart rate in patients with resistant hypertension. The first-generation Rheos^® system demonstrated more pronounced blood pressure-lowering effects, whereas the second-generation Neo^™ system was associated primarily with heart rate reduction without a significant effect on blood pressure. Although Rheos^® is no longer commercially available, these findings highlight the importance of electrode design, implantation strategy, and patient selection in optimising the efficacy of contemporary BAT.