Current Hypertension Reviews - Volume 10, Issue 1, 2014

Hypertension is a well established cardiovascular risk factor and its deleterious effects had already been largely studied. Although the benefits of adequate blood pressure (BP) control have already been demonstrated, the prevalence of persons who fail to achieve such control is alarming. A number of causes for uncontrolled hypertension can be listed. According to recent guidelines, obstructive sleep apnea (OSA) is an important, although neglected cause of hypertension that is resistant to optimal medical therapy. Specific treatment for OSA with continuous positive airway pressure (CPAP) can be a helpful adjunct to conventional pharmacological therapy to attain controlled BP levels.

Cardiovascular disease (CVD) is the leading cause of mortality worldwide and hypertension is one of the main cardiovascular risk factors. A large body of evidence have demonstrated the increased risk for CVD and mortality associated with uncontrolled hypertension and also the benefits of an adequate blood pressure (BP) control. In some cases, lack of adherence to treatment found during the evaluation of a subject with poor BP control may be part of a more complex scenario, as depression. It is known that individuals with depression have a higher risk of CVD-related morbidity and mortality, and early diagnosis and treatment have beneficial effects.

Cohort studies have demonstrated the association between blood pressure and increased cardiovascular events. There are different therapeutic strategies to achieve goals of systolic and diastolic blood pressure. For a long time, therapeutic targets were not well defined and the concept of "smaller is better" was used diffusely. However, clinical trials have shown the presence of a "J-curve" in different clinical situations: below a certain level of blood pressure, more aggressive reductions may not represent benefit and increase the incidence of adverse events in elderly patients, patients with coronary artery disease, patients with diabetes or chronic renal failure.

Hypertension is a major cardiovascular (CV) risk factor and elevated blood pressure poses a significant burden for the whole CV hemodynamics. Along the last decades different techniques and resources have been developed, including ultrasound´s M-mode and B-mode, spectral Doppler, tissue Doppler and color Doppler. Techniques from newer resources as speckle tracking, twist and tridimensional ultrasound are continuously being inserted in the echocardiography labs routine around the world. Many of the older and newer techniques interpretation have a subject component from the echocardiographer. The clinician must have minimum technical echocardiography knowledge and assess if the echocardiogram data match clinical and other exams data. Systemic arterial hypertension leads to morphologic and hemodynamic changes in the heart. These changes are signals of progressive damage along the years. Echocardiography is a powerful tool to assess these diagnostic and prognostic information.

Hyperactivity of sympathetic nervous system is one of the main mechanisms to play a role in the pathophysiology of hypertension. Its high prevalence and the low rates of adequate blood pressure control with pharmacological treatment brought interest to novel therapeutical strategies. Percutaneous renal sympathetic denervation emerged as an effective and safe alternative to reduce blood pressure in patients with resistant hypertension. Other potential indications to this procedure are heart failure, cases of insulin resistance, obesity, obstructive sleep apnea and cardiac arrhythmias.

Perioperative hypertension has been shown to be a risk factor for the development of perioperative morbidity and mortality. The time spent outside acceptable blood pressure ranges, in a state of hypertension or hypotension, is correlated with the incidence of stroke, acute coronary syndrome, renal dysfunction, and death. The ideal perioperative treatment of hypertension would include an easily titratable agent, with fast onset and offset and minimal side effects. Several medication classes are routinely used in the operating room, including, but not limited to, beta-blockers, calcium channel blockers, nitrates, and angiotensin-converting enzyme (ACE) inhibitors.Proper treatment of chronic hypertension and continuation of chronic anti-hypertensive medications in the perioperative period has been demonstrated to improve patient outcomes. This review article will outline the importance of perioperative blood pressure management, the treatment pitfalls, and the novel medications being used in the perioperative setting.

Arterial stiffness has been recognized as an independent risk factor for cardiovascular morbidity and mortality in hypertension. The activity of the renin-angiotensin system(RAS) is well-known to be involved in the control of blood pressure, and pathogenesis and evolution of several cardiovascular diseases. Although data relating the RAS activity to arterial stiffness are incomplete, there is growing evidence which shows that drugs which interfere with angiotensin II reduce arterial stiffness. This brief review is to summarize the various effects of commonly used antihypertensive agents on arterial stiffness and to present clinical trials regarding RAS modulation in stiffness reduction.

Background: Poor adherence is thought to be one of the major common causes of uncontrolled high blood pressure over the world leading to useless drug dose or class changes which may lead to increased adverse effects and medical costs. The current study aimed to investigate the relationship between knowledge about complications related to hypertension and adherence to antihypertensive treatment. Materials and Methods: A cross-sectional study was carried out between May and November 2013 on a representative sample of 453 hypertensive patients at public primary care outpatients in the department of Tlemcen in Algeria. The adherence was assessed with the adherence evaluation scale of Girerd which contains six items with closed dichotomous responses (yes/no). The degree of adherence was calculated according to the score resulting from the sum of all "yes" answers. A cut-off value of 80% was used to categorize patients as "adherent" or "non-adherent". To do so, a structured questionnaire has been performed including patients’ knowledge about hypertension complications and the other factors which may affect adherence therapy. Results: Among the 453 patients included in the study, only 35.5% were adherents. Univariate analysis has shown a positive relationship between knowledge about hypertension complications and adherence. However, comorbidities, and number of antihypertensive drugs prescribed, were associated with poor adherence. In a multivariate analysis, a significant difference was shown between adherents and non-adherents according to the factors mentioned above and the insurance status. Conclusion: This study has shown a positive relationship between patients’ knowledge about the hypertensive complications and adherence. In contrast, increased number of antihypertensive drugs taken May affect negatively the adherence to therapy.

Arterial stiffness is a vascular measure that has been reported to predict cardiovascular events. It is important to measure arterial stiffness in order to determine current vascular status and treatment strategy. Brachial-ankle pulse wave velocity (baPWV) is a unique measure of systemic arterial stiffness that is measured by brachial and tibial arterial wave analyses. Measurement of baPWV is easy and is reproducible. For more than a decade, this measure has been used broadly in East Asian countries. Meta-analysis of cohort studies conducted in the general population with hypertension, diabetes, or end-stage renal disease, and other high-risk individuals have shown that a 1 m/s increase in baPWV is associated with 12% increase in the risk of cardiovascular events. Thus, the Japanese Circulation Society has proposed that a baPWV of 1800 cm/s is a threshold for high-risk category. For baPWV to be clinically applicable, we must confirm that circulation of the lower limbs are normal by examining brachial ankle blood pressure index. In cases of peripheral arterial disease, the reliability of baPWV measurement is attenuated. To further confirm the clinical usefulness of this measure, we need to examine the hypothesis that baPWV-guided therapy could improve prognosis in high-risk patients.

Background: To investigate the long term efficacy of carotid denervation by adventitial stripping of the internal carotid artery (ICA) for carotid sinus syndrome (CSS). Secondly, the long term safety of this technique is investigated with emphasis on the effects on blood pressure (BP), heart rate (HR) and carotid artery diameter. Methods: Characteristics of patients that were operated for CSS in a single institute between 1980-2007 were studied by a retrospective chart review. Alive and fit patients additionally received a standardized interview investigating symptoms of residual CSS or baroreflex failure. They underwent a test panel consisting of office BP measurement, carotid sinus massage (CSM), table tilt testing, 24-hour ECG and ambulatory BP measurement (ABPM) and carotid duplex. Unoperated, age- and sex- matched individuals without CSS served as controls. Results: After a total follow up of 91±34 months, 22 of 26 patients (85%) were asymptomatic and 20 of them (77%) without a pacemaker. Of the 7 surviving and fit patients, six were free of CSS symptoms (follow up 114 ± 81 months). Recurrence of CSS after an initial successful carotid denervation was not observed. BP level, BP variability and carotid diameters were not different compared to controls. Conclusion: Carotid denervation by adventitial stripping of the ICA for CSS seems effective and safe on the long term. A randomized controlled trial comparing the efficacy and safety of carotid denervation, pacing and medical treatment is needed for optimal future treatment of patients suffering from CSS.