Organ damage changes in patients with resistant hypertension randomized to renal denervation or spironolactone: The DENERVHTA (Denervación en Hipertensión Arterial) study

Echocardiographic findings following renal sympathetic denervation for treatment resistant hypertension, the ReShape CV-risk study

OBJECTIVE

The aim of this study was to describe and compare echocardiographic findings before renal sympathetic denervation (RDN) and 6 and 24 months after the procedure.

MATERIALS AND METHODS

Patients with treatment resistant hypertension (TRH) were included in this non-randomised intervention study. RDN was performed by a single experienced operator using the Symplicity Catheter System. Echocardiographic measurements were performed at baseline, and after 6 and 24 months.

RESULTS

The cohort consisted of 21 patients with TRH, with a mean systolic office blood pressure (BP) of 163 mmHg and mean diastolic BP 109 mmHg. Mixed model analysis showed no significant change in left ventricular (LV) mass index (LVMI) or left atrium volume index (LAVI) after the RDN procedure. Higher LVMI at baseline was significantly associated with greater reduction in LVMI (p < 0.001). Relative wall thickness (RWT) increased over time (0.48 mm after two years) regardless of change in BP. There was a small but significant reduction in LV end-diastolic (LVIDd) and end-systolic (LVIDs) diameters after RDN, with a mean reduction of 2.6 and 2.4 mm, respectively, after two years. Progression to concentric hypertrophy was observed only in in patients who did not achieve normal BP values, despite BP reduction after RDN.

CONCLUSION

There was no reduction of LV mass after RDN. We found a small statistically significant reduction in LVIDd and LVIDs, which together with increase in RWT can indicate progression towards concentric hypertrophy. BP reduction after RDN on its own does not reverse concentric remodelling if target BP is not achieved.

Effects of renal denervation on the kidney: albuminuria, proteinuria, and renal function

Renal denervation has attracted attention as a novel antihypertensive treatment for hypertensive patients who are poorly controlled by medicine. Clinical studies have shown the antihypertensive effects of renal denervation in patients with treatment-resistant hypertension. However, renal denervation potentially has other beneficial effects, such as improving glucose metabolism and cardioprotection beyond its antihypertensive effects. In this mini-review article, we summarize and discuss the effects of renal denervation on proteinuria, albuminuria, and renal function based on the recent findings of clinical studies, and review the renoprotective effects of renal denervation.

Renal denervation for resistant hypertension

BACKGROUND

Resistant hypertension is highly prevalent among the general hypertensive population and the clinical management of this condition remains problematic. Different approaches, including a more intensified antihypertensive therapy, lifestyle modifications or both, have largely failed to improve patients' outcomes and to reduce cardiovascular and renal risk. As renal sympathetic hyperactivity is a major driver of resistant hypertension, in the last decade renal sympathetic ablation (renal denervation) has been proposed as a possible therapeutic alternative to treat this condition.

OBJECTIVES

We sought to evaluate the short- and long-term effects of renal denervation in individuals with resistant hypertension on clinical end points, including fatal and non-fatal cardiovascular events, all-cause mortality, hospital admissions, quality of life, blood pressure control, left ventricular hypertrophy, cardiovascular and metabolic profile and kidney function, as well as the potential adverse events related to the procedure.

SEARCH METHODS

For this updated review, the Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials up to 3 November 2020: Cochrane Hypertension's Specialised Register, CENTRAL (2020, Issue 11), Ovid MEDLINE, and Ovid Embase. The World Health Organization International Clinical Trials Registry Platform (via CENTRAL) and the US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov were searched for ongoing trials. We also contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) that compared renal denervation to standard therapy or sham procedure to treat resistant hypertension, without language restriction.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data and assessed study risk of bias. We summarised treatment effects on available clinical outcomes and adverse events using random-effects meta-analyses. We assessed heterogeneity in estimated treatment effects using Chi² and I² statistics. We calculated summary treatment estimates as a mean difference (MD) or standardised mean difference (SMD) for continuous outcomes, and a risk ratio (RR) for dichotomous outcomes, together with their 95% confidence intervals (CI). Certainty of evidence has been assessed using the GRADE approach.

MAIN RESULTS

We found 15 eligible studies (1416 participants). In four studies, renal denervation was compared to sham procedure; in the remaining studies, renal denervation was tested against standard or intensified antihypertensive therapy. Most studies had unclear or high risk of bias for allocation concealment and blinding.  When compared to control, there was low-certainty evidence that renal denervation had little or no effect on the risk of myocardial infarction (4 studies, 742 participants; RR 1.31, 95% CI 0.45 to 3.84), ischaemic stroke (5 studies, 892 participants; RR 0.98, 95% CI 0.33 to 2.95), unstable angina (3 studies, 270 participants; RR 0.51, 95% CI 0.09 to 2.89) or hospitalisation (3 studies, 743 participants; RR 1.24, 95% CI 0.50 to 3.11). Based on moderate-certainty evidence, renal denervation may reduce 24-hour ambulatory blood pressure monitoring (ABPM) systolic BP (9 studies, 1045 participants; MD -5.29 mmHg, 95% CI -10.46 to -0.13), ABPM diastolic BP (8 studies, 1004 participants; MD -3.75 mmHg, 95% CI -7.10 to -0.39) and office diastolic BP (8 studies, 1049 participants; MD -4.61 mmHg, 95% CI -8.23 to -0.99). Conversely, this procedure had little or no effect on office systolic BP (10 studies, 1090 participants; MD -5.92 mmHg, 95% CI -12.94 to 1.10). Moderate-certainty evidence suggested that renal denervation may not reduce serum creatinine (5 studies, 721 participants, MD 0.03 mg/dL, 95% CI -0.06 to 0.13) and may not increase the estimated glomerular filtration rate (eGFR) or creatinine clearance (6 studies, 822 participants; MD -2.56 mL/min, 95% CI -7.53 to 2.42).  AUTHORS' CONCLUSIONS: In patients with resistant hypertension, there is low-certainty evidence that renal denervation does not improve major cardiovascular outomes and renal function. Conversely, moderate-certainty evidence exists that it may improve 24h ABPM and diastolic office-measured BP. Future trials measuring patient-centred instead of surrogate outcomes, with longer follow-up periods, larger sample size and more standardised procedural methods are necessary to clarify the utility of this procedure in this population.

Kidney function and markers of renal damage after renal denervation. Does method of measurement matter? The Reshape CV-Risk Study

Data suggest that renal denervation (RDN) in treatment‐resistant hypertension (TRHT) is safe in terms of renal function. However, most studies report kidney function as creatinine‐based estimated glomerular filtration rate (eGFR), which may be biased by non‐renal factors. Damage markers other than albuminuria have never been evaluated after RDN. In this non‐randomized RDN trial, we studied changes in kidney function, assessed as measured GFR (mGFR) and various GFR estimates, six months and two years after RDN. We also examined changes in albuminuria and a biomarker of tubular dysfunction. Adult non‐diabetic patients with TRHT and eGFR ≥45 ml/min/1.73 m² were recruited from hypertension clinics. Before bilateral RDN, mGFR was measured by iohexol clearance. We estimated eGFR from serum creatinine and cystatin C (eGFR_crea, eGFR_cys, and eGFR_creacys), and albumin‐creatinine ratio (ACR) and N‐acetyl‐β‐D‐glucosaminidase (NAG)‐creatinine ratio (NAG‐CR) were measured in spot urines. All measurements were repeated after six and twenty‐four months.

Twenty patients, mean age 54 (±9) years and baseline mGFR 83 (±20) ml/min/1.73 m² underwent RDN. After six months, mGFR fell, eGFR_crea remained unchanged, whereas eGFR_cys and eGFR_creacys increased. At 2 years’ follow‐up, eGFR_creacys was significantly lower than at baseline. mGFR was 78 (±28) ml/min/1.73 m². Change in ambulatory systolic BP predicted change in eGFR_crea. Urinary NAG‐CR, but not ACR, increased during follow‐up.

Different GFR assessments gave diverging results after RDN. Therefore, care should be taken to method when evaluating kidney function after RDN. Increases in a tubular dysfunction biomarker suggest that kidney damage may occur. Long‐term renal follow‐up is needed after RDN.

Effect of Mineralocorticoid Receptor Blockade on Arterial Stiffness and Endothelial Function: A Meta-Analysis of Randomized Trials

Although numerous studies have confirmed the beneficial effects of pharmacological therapy for arterial stiffness and endothelial dysfunction, which are predictors/therapeutic targets for cardiovascular diseases, only a few overall quantitative evaluations of MRAs (mineralocorticoid receptor antagonists) exist. We searched PubMed and Cochrane CENTRAL (Cochrane Central Register of Controlled Trials) for randomized trials evaluating MRA effects on arterial stiffness measured by pulse wave velocity (PWV) or augmentation index and endothelial function measured by flow-mediated dilation. Data from the included trials were pooled by using random-effects meta-analysis of the weighted mean difference (MD) between the comparator groups. The primary outcome was the MD of PWV. In 11 trials including 515 patients, the MRA treatment reduced the PWV when compared with control (MD, -0.75 m/s [95% CI, -1.12 to -0.39], P<0.00001), without heterogeneity. There were comparable effects of MRA on carotid-femoral PWV and those on other forms of PWV (P=0.705 for heterogeneity). The effects of MRA on PWV were independent of blood pressure reduction related to the treatment according to meta-regression analysis. The MRA treatment reduced the augmentation index compared with control in 5 trials including 283 patients (MD, -6.74% [95% CI, -10.26 to -3.21], P=0.0002) and increased the flow-mediated dilation in 11 trials including 570 patients (MD, 1.18% [95% CI, 0.14 to 2.23], P=0.03). In conclusion, the current meta-analysis demonstrates the beneficial effects of MRA on PWV, augmentation index, and flow-mediated dilation.

Renal Denervation for Resistant Hypertension: Where Do We Stand?

PURPOSE OF REVIEW

To review the data about the use of renal denervation (RDN), a minimally invasive surgery, for resistant hypertension (RH) and to provide practical guidance for practitioners who are establishing an RDN service.

RECENT FINDINGS

RDN can selectively ablate renal sympathetic nerve fibres, block the transmission of nerve impulses between central sympathetic nerve and kidney, to control blood pressure to as a novel promising non-drug treatment option for RH. At present, there are many researches on the treatment of RH by RDN, but there are some controversies. This review summarises and critically examines the evidence for RDN in the treatment of RH and identifies areas for future research. With the development of RDN, the continuous innovation of RDN technology and methods, the development about better evaluating the real-time success of RDN and the improvement for identifying individuals who are most likely to benefit from RDN will ultimately determine whether RDN represents a feasible way to manage RH in the future.

Effects of mineralocorticoid receptor antagonists in proteinuric kidney disease: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Reductions in albuminuria of more than 30% are considered a strong marker of delay of chronic kidney disease (CKD) progression. Single renin-angiotensin system (RAS) blockade represents the cornerstone of CKD treatment. However, as CKD progression still occurs, other nephroprotective options were explored; mineralocorticoid receptor antagonists (MRA) were tested with generally positive results.

METHODS

We conducted a systematic review and meta-analysis on the effects of MRAs on albuminuria/proteinuria, and adverse events, such as change in renal function and hyperkalemia incidence. A detailed search in electronic databases, clinical trial registries and grey literature was performed to retrieve randomized controlled trials (RCTs) in which administration of an MRA alone or on-top of ACEi/ARB was compared with placebo or active treatment.

RESULTS

Of the 45 initially identified reports, 31, with 2767 participants, were included in analysis of the primary outcome. The use of MRAs (alone or on top of RAS blockade) compared with placebo decreased urine albumin-to-creatinine ratio (UACR) by -24.55% (95% CI -29.57 to -19.53%), urine protein-to-creatinine ratio (UPCR) by -53.93% (95% CI -79% to -28.86%) and 24 h albumin excretion by -32.47% (95% CI -41.1 to -23.85%). MRAs also reduced UACR by -22.48% (95% CI -24.51 to -20.44%) compared with calcium-channel-blockers (CCBs), whereas no differences were found compared with a second ACEi/ARB or nonpotassium-sparing diuretics. Addition of an MRA was associated with change in estimated glomerular filtration rate (eGFR) of -2.38 ml/min per 1.73 m (95% CI -3.51 to -1.25), rise in potassium by 0.22 mEq/l (95% CI 0.16-0.28 mEq/l) and a 2.6-fold increase in hyperkalemia risk (RR 2.63, 95% CI 1.69-4.08) compared with placebo/active control.

CONCLUSION

Use of MRAs alone or on top of RAS blockade confers important antiproteinuric effects in patients with CKD, with a slight increase in mean potassium levels.

[Features of Cardiovascular Risk Factors, Target Organ Damage in Patients with Diabetes Mellitus Type 2 and Arterial Hypertension]

AIM

to investigate relationship between arterial hypertension (AH) and risk factors / subclinical damage of target organs in patients with type 2 diabetes mellitus (DM2).

METHODS

We included into this clinical epidemiological study 528 patients with DM2 (30.5 % men, 69.5 % women; mean age 54.1±0.3 years; 80.3 % with AH, 19.7 % without AH), who answered questions of the ARIC study questionnaire related to risk factors. Also, we studied features of target organ damage and laboratory indicators.

RESULTS

In comparison with normotensives patients with AH more frequently had ischemic heart disease (12.7±1.6 % vs. 5.8±2.3 %, p&lt;0.05), chronic heart failure (CHF) (30.9±2.2 % vs. 9.6±2.9 %, p&lt;0.001), atherosclerosis of vessels of lower extremities (69.8±2.2 % vs. 53.8±4.9 %, p&lt;0.01) and cerebral vessels (50.9±2.4 % vs. 28.8±4.4 %, p&lt;0.001), history of stroke (5.0±1.1 % vs. 0 %, p&lt;0.05), hypertonic angiopathy (14.5±1.8 % vs. 6.5±2.5 %, p&lt;0.05), low level of high density lipoprotein (87.3±2.2 % vs. 74.5±6.4 %, p&lt;0.05), electro- and echocardiographic signs of left ventricular hypertrophy (75.6±2.1 % vs. 45.4±5.1 %, p&lt;0.001; 61.1±2.6 % vs. 24.4±4.7 %, p&lt;0.001, respectively), lowering of left ventricular ejection fraction (12.5±1.7 % vs. 7.8±2.8 %, p&lt;0.001), diastolic disfunction of the left ventricle (52.6±2.7 % vs. 23.2±4.7 %, p&lt;0.001), atherosclerosis of the aorta (38.0±2.6 % vs. 20.7±4.5 %, p&lt;0.01), lowering of the ankle-brachial index (left - 29.8±2.3 % vs. 14.9±3.5 %, p&lt;0.01; right - 31.5±2.3 % vs. 9.9±3.0 %, p&lt;0.001, respectively), increased intima-media thickness of the right carotid artery (84.6±5.0 % vs. 60.0±11.0 %, p&lt;0.05).

CONCLUSION

In patients with type 2 diabetes and AH, in order to develop strategy of macro- and microvascular complications prevention, it is necessary to conduct early screening of risk factors and subclinical damage of target organs.

Urine Haptoglobin and Haptoglobin-Related Protein Predict Response to Spironolactone in Patients With Resistant Hypertension

Resistant hypertension prevalence is progressively increasing, and prolonged exposure to suboptimal blood pressure control results in higher cardiovascular risk and end-organ damage. Among various antihypertensive agents, spironolactone seems the most effective choice to treat resistant hypertension once triple therapy including a diuretic fails. However success in blood pressure control is not guaranteed, adverse effects are not negligible, and no clinical tools are available to predict patient's response. Complementary to our previous study of resistant hypertension metabolism, here we investigated urinary proteome changes with potential capacity to predict response to spironolactone. Twenty-nine resistant hypertensives were included. A prospective study was conducted and basal urine was collected before spironolactone administration. Patients were classified in responders or nonresponders in terms of blood pressure control. Protein quantitation was performed by liquid chromatography-mass spectrometry; ELISA and target mass spectrometry analysis were performed for confirmation. Among 3310 identified proteins, HP (haptoglobin) and HPR (haptoglobin-related protein) showed the most significant variations, with increased levels in nonresponders compared with responders before drug administration (variation rate, 5.98 and 7.83, respectively). Protein-coordinated responses were also evaluated by functional enrichment analysis, finding oxidative stress, chronic inflammatory response, blood coagulation, complement activation, and regulation of focal adhesions as physiopathological mechanisms in resistant hypertension. In conclusion, protein changes able to predict patients' response to spironolactone in basal urine were here identified for the first time. These data, once further confirmed, will support clinical decisions on patients' management while contributing to optimize the rate of control of resistant hypertensives with spironolactone.