Stretching the carotid sinus to treat resistant hypertension

Abstract

Around a quarter of adults have hypertension, and by 2025, the number affected might be more than 1·5 billion people worldwide. 1 Olsen MH Angell SY Asma S et al. A call to action and a lifecourse strategy to address the global burden of raised blood pressure on current and future generation: the Lancet Commission on hypertension. Lancet. 2016; 388: 2665-2712 Summary Full Text Full Text PDF PubMed Scopus (484) Google Scholar Despite important advances in pharmacotherapy in the past 40 years, resistant hypertension—that is, persistently raised ambulatory blood pressure despite treatment with at least three antihypertensive drugs, including a diuretic—occurs in about 13% of treated adults. 2 Calhoun DA Jones D Textor S et al. Resistant hypertension: diagnosis, evaluation, and treatment. A scientific statement from the American Heart Association Professional Education Committee of the Council for High Blood Pressure Research. Hypertension. 2008; 51: 1403-1419 Crossref PubMed Scopus (1230) Google Scholar Optimisation of treatment is crucial in people with resistant hypertension because of the increased risk of cardiovascular disease. Two main pathophysiological mechanisms can be targeted: volume excess related to dietary sodium, reduced renal function, or aldosterone excess; and vascular resistance increased by overactivity of the renin–angiotensin–aldosterone system (RAAS) or sympathetic nervous system. Excess volume may be counterbalanced by use of high-dose diuretics or by adding a mineralocorticoid-receptor antagonist. 3 Williams B MacDonald TM Morant S et al. Spironolactone versus placebo, bisoprolol, and doxazosin to determine the optimal treatment for drug resistant hypertension (PATHWAY-2): a randomised, double-blind, crossover trial. Lancet. 2015; 386: 2059-2068 Summary Full Text Full Text PDF PubMed Scopus (676) Google Scholar Vascular resistance may be reduced with RAAS blockers, β blockers, or interventional strategies. The baroreflex, which is controlled by the sympathetic nervous system, is mainly directed at short-term control of blood pressure. Several concepts have emerged suggesting that strong interactions between the sympathetic nervous system, the kidneys, and the RAAS contribute to long-term regulation of blood pressure. 4 Lohmeier TE Iliescu R The baroreflex as a long-term controller of arterial pressure. Physiology. 2015; 30: 148-158 Crossref PubMed Scopus (78) Google Scholar Device therapies have been developed to target the sympathetic nervous system by baroreceptor stimulation or renal denervation. 5 Courand PY Feugier P Workineh S et al. Baroreceptor stimulation for resistant hypertension: first implantation in France and literature review. Arch Cardiovasc Dis. 2014; 107: 690-696 Crossref PubMed Scopus (10) Google Scholar Endovascular baroreflex amplification for resistant hypertension: a safety and proof-of-principle clinical studyIn patients with resistant hypertension, endovascular baroreceptor amplification with the MobiusHD device substantially lowered blood pressure with an acceptable safety profile. Randomised, double-blind, sham-controlled trials are warranted to investigate the use of this treatment further. Full-Text PDF