Treating resistant hypertension: role of renal denervation

2022 Malaysian Working Group Consensus Statement on Renal Denervation for management of arterial hypertension

Hypertension is highly prevalent and a major contributor to cardiovascular mortality and morbidity. In spite of the availability of efficacious, safe and affordable anti-hypertensive drugs, hypertension remains poorly controlled in the majority of hypertensive patients. Various reasons including non-adherence to the anti-hypertensive drugs, account for the poor control. Resistant hypertension is also one of the reasons for poor control of blood pressure (BP). The sympathetic nervous system (SNS) has long been recognized as one of the determinants in the pathophysiology of a raised BP. Overactivity of the SNS is a contributor to sustained arterial hypertension. Renal denervation (RDN) is increasingly recognized as a safe and effective adjunctive therapy to control BP with or without pharmacotherapy. Hence for patients who remain uncontrolled despite all efforts, renal denervation (RDN) is a novel treatment that can potentially improve BP control, hence reducing the major adverse cardiovascular events (MACE). More recent randomized, sham control trials of RDN have shown that RDN produces a sustained lowering of BP. To date, this lowering of BP through RDN is maintained for at least 3 years. Furthermore, this procedure has been found to be safe. Hence this consensus summarises the science behind RDN and the available clinical data to support the use of this therapy. It is hoped that this consensus will offer guidance on the importance of identifying patients who will benefit most from this therapy. A multidisciplinary team approach in the management of the patient undergoing RDN is recommended.

Apparent therapy-resistant hypertension as risk factor for the development of type 2 diabetes mellitus

OBJECTIVE

To evaluate whether the relationship between hypertension and type 2 diabetes mellitus (T2DM) is different for patients with uncontrolled hypertension, controlled hypertension or patients with apparent therapy-resistant hypertension (aTRH), compared with patients without hypertension.

METHODS

Using Cox proportional hazard models we evaluated the risk of new-onset T2DM in 8756 patients, at high risk for vascular disease. Hypertensive patients were subdivided according to blood pressure (BP) and use of BP-lowering drugs. BP ≥ 140/90 mmHg was defined as uncontrolled BP. aTRH was defined as uncontrolled BP despite being treated with at least three BP-lowering drugs including a diuretic, or the use at least four BP-lowering drugs irrespective of BP levels. Further analysis evaluated the risk of new-onset T2DM for patients with uncontrolled hypertension and for patients with aTRH, compared with patients with controlled hypertension and without hypertension, respectively.

RESULTS

Forty-five percent had controlled hypertension, 20% had uncontrolled hypertension, 5.7% had aTRH, and 29% were nonhypertensive. During a follow-up of 7.0 (interquartile range: 0-14) years there were 705 new cases of T2DM. Patients with hypertension had a 1.48 (95% confidence interval 1.22-1.80) times higher risk of new-onset T2DM than nonhypertensive patients. There was no significant difference in risk among different hypertension groups.

CONCLUSION

Patients at high risk for cardiovascular disease with hypertension have a 1.48 times higher risk of new-onset T2DM than nonhypertensive counterparts. The risk did not differ between patients with controlled hypertension, uncontrolled hypertension, or aTRH.

Exercise as a tool for hypertension and resistant hypertension management: current insights

Although there has been an observed progress in the treatment of hypertension, its prevalence remains elevated and constitutes a leading cause of cardiovascular disease development. Resistant hypertension is a challenge for clinicians, as the available treatment options have reduced success. Physical activity and exercise training play an important role in the management of blood pressure. The importance of physical activity and exercise training as part of a comprehensive lifestyle intervention is acknowledged by several professional organizations in their recommendations/guidelines for the management of arterial hypertension. Aerobic exercise, dynamic resistance exercise, and concurrent training - the combination of dynamic resistance and aerobic exercise training in the same exercise session or on separate days - has been demonstrated to reduce blood pressure and help in the management of hypertension. The present review draws attention to the importance of exercise training in the management of blood pressure in both hypertension and resistant hypertension individuals.

Sleep patterns and cardiometabolic risk in schoolchildren from Cuenca, Spain

Sleep seems to have a significant influence on the metabolic syndrome (MetS). However, results in this association are still inconsistent in children. The aim of this study was to examine the influence of sleep characteristics in the MetS (index and factors) in Spanish children. Cross-sectional study including a sample of 210 children aged 8-to-11-years belonging to 20 schools from the province of Cuenca, Spain was conducted. Cardiometabolic risk and actigraphy sleep patterns were determined and analysed using correlation coefficients, ANCOVA models and a propensity score derivation model. Overall, children in the lower time in bed category and those who went to bed later (> 23:15h) showed worse values in the cardiometabolic profile and risk index. Differences were observed when the total time in bed was below 9h 15mins. Our study shows that short sleep duration could be a risk factor for cardiometabolic risk in children, and bedtime may independently influence this risk. In addition, our data suggests that children’s sleep hygiene should be incorporated in parenting educational programs.

[Criteria for selecting patients with resistant hypertension for a renal sympathetic denervation]

AIM

to define and develop a procedure that can select patients with resistant hypertension (RH) for a renal sympathetic denervation (RSD) procedure, by being orienting to the specific initial values of β-adrenoreactivity (β-AR) and systolic blood pressure (SBP).

SUBJECTS AND METHODS

The analysis included 23 RH patients receiving the maximally tolerable doses of 4 antihypertensive drugs. The investigations involving BP control and a Russian spectrophotometric procedure for determining β-AR in terms of the change in the osmoresistance of erythrocyte membranes (EM) were performed at baseline and 4 and 24 weeks. RSD was carried out using endovascular radiofrequency ablation of the renal arteries. The therapy was not changed during the observation.

RESULTS

If SBP was >170 mm Hg and β-AR of EM >40 conditional units (CUs) at baseline, ΔSBP was 17.68±3.24 mm Hg and the efficiency of RSD was 100%. When SBP was <170 mm Hg and β-AR of EM <40 CUs at baseline, ΔSBP was 0.97±4.21 mm Hg (p>0.05) and the efficiency of RSD was low.

CONCLUSION

The overall estimate of baseline SBP and β-AR of EM in patients with RH could determine the expediency of the RSD procedure in order to lower BP. The proposed procedure can optimize the selection of patients and enhance the efficiency of RSD in the treatment of RH.

The efficacy of antihypertensive drugs in chronic intermittent hypoxia conditions

Sleep apnea/hypopnea disorders include centrally originated diseases and obstructive sleep apnea (OSA). This last condition is renowned as a frequent secondary cause of hypertension (HT). The mechanisms involved in the pathogenesis of HT can be summarized in relation to two main pathways: sympathetic nervous system stimulation mediated mainly by activation of carotid body (CB) chemoreflexes and/or asphyxia, and, by no means the least important, the systemic effects of chronic intermittent hypoxia (CIH). The use of animal models has revealed that CIH is the critical stimulus underlying sympathetic activity and hypertension, and that this effect requires the presence of functional arterial chemoreceptors, which are hyperactive in CIH. These models of CIH mimic the HT observed in humans and allow the study of CIH independently without the mechanical obstruction component. The effect of continuous positive airway pressure (CPAP), the gold standard treatment for OSA patients, to reduce blood pressure seems to be modest and concomitant antihypertensive therapy is still required. We focus this review on the efficacy of pharmacological interventions to revert HT associated with CIH conditions in both animal models and humans. First, we explore the experimental animal models, developed to mimic HT related to CIH, which have been used to investigate the effect of antihypertensive drugs (AHDs). Second, we review what is known about drug efficacy to reverse HT induced by CIH in animals. Moreover, findings in humans with OSA are cited to demonstrate the lack of strong evidence for the establishment of a first-line antihypertensive regimen for these patients. Indeed, specific therapeutic guidelines for the pharmacological treatment of HT in these patients are still lacking. Finally, we discuss the future perspectives concerning the non-pharmacological and pharmacological management of this particular type of HT.

Endothelium and its alterations in cardiovascular diseases: life style intervention

The endothelium, which forms the inner cellular lining of blood vessels and lymphatics, is a highly metabolically active organ that is involved in many physiopathological processes, including the control of vasomotor tone, barrier function, leukocyte adhesion, and trafficking and inflammation. In this review, we summarized and described the following: (i) endothelial cell function in physiological conditions and (ii) endothelial cell activation and dysfunction in the main cardiovascular diseases (such as atherosclerosis, and hypertension) and to diabetes, cigarette smoking, and aging physiological process. Finally, we presented the currently available evidence that supports the beneficial effects of physical activity and various dietary compounds on endothelial functions.