Several reasons make resistant hypertension an issue of major current interest. To mention just a few, this condition (which is defined as absence of blood pressure control despite multidrug treatment at adequate individual drug doses) is by no means rare. Although varying with the clinical setting in which resistant hypertension is studied, the consensus is that this condition may affect about 10% of the overall hypertensive population, which amounts to more than 6 million patients in the USA and more than 10 millions in Europe.
Secondly, patients with resistant hypertension have a high cardiovascular risk, with a much greater chance of developing heart failure, cerebrovascular or coronary disease, and endstage renal disease than patients in which blood pressure is more easily controlled.
Thirdly, there is a great deal of uncertainty on which antihypertensive drugs should be added when the three-drug regimen turns out to be ineffective or only partially effective. All drugs with mechanisms of action different from the currently administered ones have a chance of leading to some blood pressure reduction, but for each of them the effect involves only a limited number of cases and little information is available on: 1) whether some drugs are on average better than others and 2) which drug has a greater chance to work in which patient.
Finally, recent studies suggest that in resistant hypertension blood pressure can be reduced with invasive procedures such as renal denervation and carotid baroreceptor stimulation, pointing to sympathetic hyperactivity as an important mechanism in the maintenance of the persistent blood pressure elevation.
Although the evidence is still incomplete, this represents a new promising therapeutic approach, whose availability has greatly stimulated research in this area. A demonstration is the striking, progressive increase in the number of studies on resistant hypertension which have taken place in the last 4 years, with new information not only on its treatment but also on its epidemiological, pathophysiological and diagnostic aspects.
1. Resistant Hypertension: Definition, Prevalence, and Cardiovascular Risk.
Part I: Pathophysiology
2. Resistant Hypertension: Neurohumoral Aspects.
3. Metabolic Alterations
4. Cardiac and Vascular Alterations in Resistant Hypertension
5. The Pathophysiology of the Kidney in Resistant Hypertension
Part II: Diagnostic Aspects
6. False Versus True Resistant Hypertension.
7. Causes of Resistant Hypertension
8. 24-hour Ambulatory BP Monitoring and Home BP Measurements in Resistant Hypertension
9. Factors Predicting Blood Pressure Response to Treatment
10. Treatment of Resistant Hypertension. Which Additional Antihypertensive Drugs?
11. The Role of Renal Denervation
12. The Role of Carotid Baroreceptor Stimulation
13. Pathophysiology: Metabolic Alterations and Risk Factors
14. Follow-up of Patients with Resistant Hypertension.
15. Resistant Hypertension: Cost-Benefit Considerations
16. Involvement of Health Professionals: From the General Practitioner to the Hypertension Specialist and the Hypertension Center
Title: Resistant Hypertension: Epidemiology, Pathophysiology, Diagnosis and Treatment
Author: Giuseppe Mancia