Blood pressure after blinded, randomized withdrawal, and resumption of baroreceptor-activating therapy

BACKGROUND: Baroreceptor-activating therapy (BAT) has been shown to control resistant hypertension in one sham-controlled and further observational studies. Incremental but significant reincrease of blood pressure (BP) have been described after open-label temporary withdrawal of such therapy. METHOD: Our study in 16 randomized patients investigated the course of automated office, ambulatory, and home BP in a randomized, controlled cross-over design. RESULTS: After 4 weeks of blinded and randomized withdrawal in hypertension-controlled long-term carriers of BAT (2.67 ± 1.3 years, 145/104 mmHg), the primary end point of 35 mmHg difference, similar to initial BP drop after BAT initiation, was not reached in any patient. Ambulatory BP rose significantly during BAT off by 10/8 ± 4/3 mmHg (3.13/2.10, P = 0.007/0.002) and automated office BP by 10/4 ± 2/1 (4.17/0.58, P = 0.005/0.03) at 4 weeks after BAT on while mean home BP did not change significantly by 2/2 ± 3/2 mmHg (-5.9/-3.5, P = 0.6/0.5). CONCLUSION: Our data in a limited study population show, that BP rise after temporary BAT withdrawal is significant but does not reach a magnitude comparable with the initial drop after de novo implantation. Such results points to preserved hypertension control after electrical BAT withdrawal and deserves further pathophysiological and clinical clarification.