Electrical Carotid Sinus Stimulation: Chances and Challenges in the Management of Treatment Resistant Arterial Hypertension

Abstract

Treatment resistant arterial hypertension is associated with excess cardiovascular morbidity and mortality. Electrical carotid sinus stimulators engaging baroreflex afferent activity have been developed for such patients. Indeed, baroreflex mechanisms contribute to long-term blood pressure control by governing efferent sympathetic and parasympathetic activity. The first-generation carotid sinus stimulator applying bilateral bipolar stimulation reduced blood pressure in a controlled clinical trial but nevertheless failed to meet the primary efficacy endpoint. The second-generation device utilizes smaller unilateral unipolar electrodes, thus decreasing invasiveness of the implantation while saving battery. An uncontrolled clinical study suggested improvement in blood pressure with the second-generation device. We hope that these findings as well as preliminary observations suggesting cardiovascular and renal organ protection with electrical carotid sinus stimulation will be confirmed in properly controlled clinical trials. Meanwhile, we should find ways to better identify patients who are most likely to benefit from electrical carotid sinus stimulation.

Prolonged Baroreflex Activation Abolishes Salt-Induced Hypertension After Reductions in Kidney Mass

“…The first-generation system used in the present study consisting of tripolar electrodes implanted bilaterally (Rheos system) is no longer available for either experimental or clinical investigation. As cogently discussed, 4 patients currently receive only unilateral carotid sinus implants with an electrode of a different design (Barostim Neo). While recent findings using this second-generation system in patients with RHT do show blood pressure reductions with minimal or no side effects, 46–48 unlike its predecessor, the Barostim Neo electrode system has only been tested in uncontrolled clinical trials.…”

“…While recent findings using this second-generation system in patients with RHT do show blood pressure reductions with minimal or no side effects, 46–48 unlike its predecessor, the Barostim Neo electrode system has only been tested in uncontrolled clinical trials. 4–5 Notably, a recent acute study in patients employing 2 min periods of unilateral carotid sinus activation suggested that the new electrode design may diminish efficacy and tolerability. 49 However, this has not been our experience when using the Barostim Neo system during chronic bilateral carotid sinus activation in canines.…”

Chronic Interactions Between Carotid Baroreceptors and Chemoreceptors in Obesity Hypertension

“…While there is virtually no information from prospective studies or current clinical trials relating to the antihypertensive effects of carotid body ablation in humans, recent clinical trials have clearly shown that baroreflex activation reduces arterial pressure in many but not all patients with resistant hypertension. 13–17 The reasons for this variability are not well understood, but as both baroreflex activation and carotid body denervation lower arterial pressure by inhibiting sympathetic activity, the variable degree of sympathetic activation in this heterogeneous population may be a key determinant of the antihypertensive response. 19 Obesity-induced hypertension is mediated by activation of the sympathetic nervous system and obesity is common in patients with resistant hypertension.…”

“…Using this technology, significant antihypertensive responses have been reported in both experimental animals and in patients with resistant hypertension. 13–17 …”

Adrenoreceptors Blocking: Recent Data on Urapidil Usage

“…Её роль в повышении давления, в вазоконстрикции и задержке жидкости, в развитии тахикардии несомненна и известна давно. Современ-ные исследования так или иначе пытаются влиять на симпатическую активность фармакологически или физически: воздействуя на каротидный синус или денервируя почки [1,2]. Однако инвазивные или малоинвазивные вмешательства не всегда возможны и не всегда показаны.…”