Interventional activation of the carotid baroreflex has been an appealing idea for the management of resistant hypertension for several decades, yet its clinical application remained elusive and a goal for the future. It is only recently that the profound understanding of the complex anatomy and pathophysiology of the circuit, combined with the accumulation of relevant experimental and clinical data both in animals and in humans, has allowed the development of a more effective and well- promising approach. Indeed, current data support a sustained over a transient reduction of blood pressure through the resetting of baroreceptors, and technical deficits have been minimized with a subsequent recession of adverse events. In addition, clinical outcomes from the application of a new implantable device (Rheos) that induces carotid baroreceptor stimulation point towards a safe and effective blood pressure reduction, but longer experience is needed before its integration in the everyday clinical practice. While accumulating evidence indicates that carotid baroreceptor stimulation exerts its benefits beyond blood pressure reduction, further research is necessary to assess the spectrum of beneficial effects and evaluate potential hazards, before the extraction of secure conclusions. 1. Introduction Arterial hypertension represents a major public health problem around the word. Currently, more than one billion people are thought to have hypertension worldwide and the number is estimated to exceed 1.5 billion by 2025 [1]. The advent of antihypertensive therapy has provided drugs that effectively lower blood pressure and contributed significantly to the reduction of cardiovascular events [2]. The rates of awareness, treatment, and control of hypertension have been constantly increased over the last decades; they remain, however, far from optimal [3], underlining the need for the implementation of more effective approaches. Antihypertensive drugs belong to different categories, exerting their actions through different mechanisms that are sometimes complimentary. It has been shown, however, that despite the proper use of several antihypertensive agents, blood pressure remains uncontrolled in a small percentage of hypertensive patients (5%–15%). This subgroup has been called over the years as suffering from refractory, difficult to control, or resistant hypertension (lately). Although the percentage of this subgroup does not seem significant, the actual number of resistant hypertensives is estimated to be very large due to the high prevalence of hypertension in the
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