Current Hypertension Reviews - Volume 12, Issue 1, 2016

Hypertension is prevalent in patients with sleep disordered breathing (SDB). Since hypertension significantly relates to cardiovascular diseases, the treatment and prevention of SDB could be targets for the prevention of cardiovascular diseases. In this article, we summarize about epidemiology of SDB and hypertension in various populations. General population based studies on the prevalence of SDB reported that 24 to 47% male and 9 to 30% female had SDB. Furthermore, the prevalence of hypertension in individuals with SDB was high, ranging from 36 to 57%. American and Korean based studies reported that the severity of SDB related to increase of blood pressure and hypertension. In the elderly, however, the severity of SDB did not relate to increase in blood pressure and hypertension, but to dipping pattern of blood pressure. With respect to children, the severity of SDB also related to increase in blood pressure, but the trend was inconstant in children with habitual snoring. In addition to the sexual differences, the severity of SDB related to hypertension in males. On the other hand, there was no relationship between the severity of SDB and hypertension in females. SDB was prevalent in the general population, regardless of race, and affected blood pressure. We should pay attention to the subjects’ individual character when we interrupt the outcome.

Acute and sustained activation of the sympathetic nervous system are clinical hallmarks of both obstructive and central sleep apnea. Conversely, their treatment has been shown to reverse these abnormalities. The objectives of this brief review are to summarize: 1) present knowledge concerning the mechanisms, magnitude and consequences of night- and day-time sympathetic nervous system activation in patients with these sleep-related breathing disorders; and 2) the impact on the sympathetic nervous system and on blood pressure of their specific treatment.

Obstructive sleep apnea (OSA) places an enormous pressure load on the cardiovascular system by inducing a temporary blood pressure (BP) surge during apnea episodes. This pressure load is regarded as a potential mechanism of development of cardiovascular diseases such as stroke. Therefore, accurate measurement of such BP surges would be valuable for the risk stratification of OSA patients. Recently we developed a new triggered nocturnal BP monitoring system (TNP) based on oxygen desaturation and have achieved success to detect BP surges with OSA. TNP would be a promising tool for assessment of cardiovascular risks in sleep apnea syndrome.

Sleep-disordered breathing (SDB) is common and adversely affects cardiovascular morbidity and mortality. Despite multifactorial pathogenesis, SDB is prevalent in patients with fluid retention disorders, such as drug-resistant hypertension, end-stage renal disease, and heart failure, suggesting that fluid retention may play a role in the pathogenesis of SDB. During the day, fluid is likely to accumulate in the legs, and upon lying down at night is displaced from the legs. Many data suggest that some of this fluid displaced from the legs may redistribute to the upper body and predispose to SDB. This review article will highlight evidence for a relationship between SDB and fluid retention or rostral fluid shift, and discuss mechanisms that link them.

The outlines of the current manuscript are: 1. Re-establish the link between hypertension and SDB including prevalence, mechanism, and reversal of process (i.e. improvement in hypertension with improvement in SDB), why it is important-cardiovascular mortality with numbers. 2. Re-establish the link between hypertension and CKD including same points as above. Then ask if both CKD and SDB are combined, what happens to hypertension and cardiovascular mortality. 3. Lastly, talk about links between CKD and SDB on how each process feeds on the other and is a growing, common problem.

Sleep Apnea is a very common condition that has serious cardiovascular sequelae such as hypertension, heart failure, and stroke. Since the advent of modern computers and digital circuits, several streams of new technologies have been introduced to enhance the traditional diagnostic method of polysomnography and offer alternatives that are more accessible, comfortable, and economic. The categories presented in this review include portable polygraphy, mattress-like devices, remote sensing, and acoustic technologies. These innovations are classified as a function of their physical structure and the capabilities of their sensing technologies, due to the importance of these factors in determining the end-user experiences (both patients and medical professionals). Each of those categories offers unique strengths, which then make them particularly suitable for specific applications and end users. To our knowledge, this is a unique approach in presenting and classifying sleep apnea diagnostic innovations.

Primary cilia are sensory organelles that extend from the cell surface and sense extracellular signals. Endothelial primary cilia protruding from the inner surface of blood vessel walls sense changes in blood flow and convert this mechanosensation into an intracellular biochemical/molecular signal, which triggers a cellular response. Primary endothelial cilia dysfunction may contribute to the impairment of this response and thus be directly implicated in the development of vascular abnormalities such as hypertension and aneurysms. Using both in vitro techniques as well as in vivo animal models, we and others have investigated fluid flow mechanosensory functions of endothelial cilia in cultured cells, animal models and autosomal dominant polycystic kidney disease (ADPKD) patients. More in-depth studies directed at identification of the mechanisms of fluid flow sensing will further enhance our knowledge of cilia-dependent vascular pathology. Although the current treatments aimed at treating the cardiovascular symptoms in ADPKD patients successfully slowed the progression of cyst growth, there is growing evidence which suggests that drugs which interfere with primary cilia function or structure could reduce cardiovascular complications in ADPKD. This review is to summarize the most recent studies on primary endothelial cilia function in the vascular system and to present primary cilia as a novel therapeutic target for vascular hypertension.

Introduction: Hypertension is one of the most prevalent diseases in the world, with about 1 billion people affected and a possible increase to 1.5 billion by 2025. Despite advances in treatment, a proportion of patients remain resistant to conventional treatment and uncontrolled, and this can adversely affect future cardiovascular events and mortality. This alarming growth is already reflected in an important public health problem and one of the largest economic burdens of health, requiring new approaches and development of different strategies to fight this problem. Objectives: This review will focus on the definition of resistant hypertension and its etiology, as well as in contemporary evidence supporting the usefulness of renal sympathetic denervation while addressing current and emerging devices, potential treatment indications in the future and unresolved issues that need to be addressed before renal sympathetic denervation can be adopted not only as a last resort exclusively for resistant hypertension. Finally an evaluation algorithm for patients with resistant hypertension which should be implemented before the execution of this technique will be proposed. Results: Renal sympathetic denervation is a technique that possibly could have future implications in the population with hypertension, especially those with true resistant hypertension. This technique aims to reduce the renal sympathetic activation (a component in the pathophysiology of hypertension) through the destruction of the renal sympathetic nerves located in the adventitia of the renal arteries. There are several catheters that can be used; each with its specifications and therefore their selection should be made individually depending on the profile of the patient. However, a detailed pre-procedure evaluation is extremely important to exclude the large percentage of individuals with uncontrolled hypertension due to several factors that make it impossible to control blood pressure, but are likely to be corrected and as such should be treated first. Conclusion: Several studies have demonstrated the efficacy and safety both in resistant hypertension as in other co-morbidities. However, there is no marker to evaluate the effectiveness of this technique, neither a robust predictor of a stronger response in certain patients. Additionally there are several factors that seem to influence various parameters related to this technique. Therefore there is a need for additional studies to consolidate the data existing on the renal sympathetic denervation.