Interventional procedures and future drug therapy for hypertension.

Hypertension management poses a major challenge to clinicians globally once non-drug (lifestyle) measures have failed to control blood pressure (BP). Although drug treatment strategies to lower BP are well described, poor control rates of hypertension, even in the first world, suggest that more needs to be done to surmount the problem. A major issue is non-adherence to antihypertensive drugs, which is caused in part by drug intolerance due to side effects. More effective antihypertensive drugs are therefore required which have excellent tolerability and safety profiles in addition to being efficacious. For those patients who either do not tolerate or wish to take medication for hypertension or in whom BP control is not attained despite multiple antihypertensives, a novel class of interventional procedures to manage hypertension has emerged. While most of these target various aspects of the sympathetic nervous system regulation of BP, an additional procedure is now available, which addresses mechanical aspects of the circulation. Most of these new devices are supported by early and encouraging evidence for both safety and efficacy, although it is clear that more rigorous randomized controlled trial data will be essential before any of the technologies can be adopted as a standard of care.

The future of interventional management of hypertension: threats and opportunities.

In about 48% hypertensive patients in the United States, blood pressure remains higher than accepted treatment targets despite broad availability of effective pharmaceutical agents. Of these 48%, recent estimates define about 10-11% have treatment-resistant hypertension (TR-HTN). Compensatory changes in sympathetic nervous system function are an important component of HTN. Recent technical advances targeting the sympathetic activity of the carotid sinuses (Baroreflex Activation Therapy-BAT) and the renal sympathetic nerves (Renal Denervation Therapy-RDT) have renewed interest in invasive therapy for the treatment of drug-resistant hypertension. Encouraging results from the recent Rheos Pivotal and Symplicity HTN-2 trials on the safety and efficacy of BAT and RDT respectively, indicate that invasive approaches can safely reduce blood pressure in patients with resistant hypertension. The main goal of this article is to review the results of preclinical and clinical studies on the electric stimulation of the carotid sinus and the catheter-based renal denervation.

[Treatment resistant hypertension. Value of a new treatment concept]. / Therapierefraktäre Hypertonie. Stellenwert neuer Therapiekonzepte.

Sympathetic overexpression can be found in a majority of hypertensive patients. Resistant arterial hypertension requires a targeted diagnostic procedure in order to exclude secondary causes of hypertension which can be treated specifically with established therapies. If secondary reasons are not identified, the antihypertensive medication is already optimal and lifestyle changes have been realized, but still the goal of antihypertensive therapy cannot be achieved, alternative invasive therapy strategies such as renal sympathetic denervation and baroreflex activation have been developed to achieve blood pressure control. These therapies are restricted to specialized centers which treat well-defined patients with therapy-resistant hypertension. Little long-term data concerning safety and efficacy are available for the two strategies. However, they should preferably be used as an ultima-ratio and add-on pathway to conservative procedures when established medication fails to achieve blood pressure control. To date, the effectiveness of the interventional antihypertensive therapies has only been shown on patients with systolic blood pressure over 160 mmHg and a mean oral medication of five drugs.