Impact of Renal Sympathetic Denervation on Left Ventricular Structure and Function at 1-Year Follow-Up

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.

Left ventricular structure and function following renal sympathetic denervation in patients with HFpEF: an echocardiographic 9-year long-term follow-up

Background

High blood pressure is a major risk factor for cardiac remodeling and left ventricular hypertrophy, increasing cardiovascular risk and leading to heart failure with preserved ejection fraction (HFpEF). Since renal sympathetic denervation (RDN) reduces blood pressure in the long term, we aimed to investigate the long-term effect of RDN in patients with HFpEF in the present analysis.

Methods

Patients previously enrolled in a local RDN registry who underwent high-frequency RDN with the use of the Symplicity Flex® renal denervation system between 2011 and 2014 were followed up. The patients were assessed by 24-h ambulatory blood pressure measurement, transthoracic echocardiography, and laboratory tests. We used the echocardiographic and biomarker criteria of the Heart Failure Association (HFA)-PEFF (Pre-test assessment, Echocardiography and Natriuretic Peptide Score, Funkctional testing, and Final aetiology) score to identify patients with HFpEF.

Results

Echocardiographic assessment was available for 70 patients at a 9-year long-term follow-up. Of these patients, 21 had HFpEF according to the HFA-PEFF score. We found a significant reduction of the HFA-PEFF score from 5.48 ± 0.51 points at baseline to 4.33 ± 1.53 points at the 9-year follow-up (P < 0.01). This decrease was due to a greater reduction in morphological and biomarker subcategories [from 1.95 ± 0.22 to 1.43 ± 0.51 points (P < 0.01) and from 1.52 ± 0.52 to 0.90 ± 0.63 points (P < 0.01), respectively] than in the functional one. Morphologically, there was a reduction in left ventricular hypertrophy and left atrial dilation.

Conclusions

The present analysis suggests that RDN may lead to a regression of the extent of HFpEF beyond a reduction in blood pressure and thus possibly contribute to an improvement in prognosis. More detailed information will be provided by ongoing randomized sham-controlled trials.

Impact of Renal Denervation on Urinary Peptide-Based Biomarkers in Hypertension

BACKGROUND

Catheter-based renal denervation (RDN) reduces blood pressure in hypertension. Urinary peptides are associated with cardiovascular and renal disease and provide prognostic information. We aimed to investigate the effect of RDN on urinary peptide-based classifiers associated with chronic kidney and heart disease and to identify urinary peptides affected by RDN.

METHODS

This single-arm, single-center study included patients undergoing catheter-based RDN. Urine samples were collected before and 24 months after RDN and were analyzed using capillary electrophoresis coupled with mass spectrometry. Predefined urinary peptide-based classifiers for chronic kidney disease (CKD273), coronary artery disease (CAD238), and heart failure (HF1) were applied.

RESULTS

This study included 48 patients (33% female) with uncontrolled hypertension. At 24 months after RDN, systolic blood pressure (165±17 versus 148±20 mm Hg; P<0.0001), diastolic blood pressure (90±17 versus 81±13 mm Hg; P<0.0001), and mean arterial pressure (115±15 versus 103±13 mm Hg; P<0.0001) decreased significantly. A total of 103 urinary peptides from 37 different proteins, mostly collagens, altered following RDN. CAD238, a 238 coronary artery-specific polypeptide-based classifier, significantly improved following RDN (Cohen's d, -0.632; P=0.0001). The classification scores of HF1 (P=0.8295) and CKD273 (P=0.6293) did not change significantly.

CONCLUSIONS

RDN beneficially affected urinary peptides associated with coronary artery disease.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01888315.

Impact of renal denervation on cardiac remodeling in resistant hypertension: A meta-analysis

Twelve studies involving 433 patients were included. After RDN treatment, LVMI decreased by 13.08 g/m2 (95% confidence interval [CI]: -18.38, -7.78; p < .00001), PWTd decreased by 0.60 mm (95% CI: -0.87, -0.34; p < .00001), IVSTd decreased by 0.78 mm (95% CI: -1.06, -0.49; p < .00001), and LVEF increased by 1.80% (95% CI: 0.71, 2.90; p = .001). However, there were no statistically significant improvements in LVIDd (95% CI: -1.40, 0.24; p = .17) and diastolic function (E/A) (95% CI: -0.04, 0.14; p = .28). Drug treatment for resistant hypertension (RH) is challenging. Renal denervation (RDN) is one of the most promising treatments for RH. Although studies have shown RDN can control blood pressure, the impacts of RDN on cardiac remodeling and cardiac function are unclear. This meta-analysis evaluated the effect of RDN on cardiac structure and function in patients with RH. PubMed, Embase, and Cochrane were used to conduct a systematic search. The main inclusion criteria were studies on patients with RH who received RDN and reported the changes in echocardiographic parameters before and after RDN. Echocardiographic parameters included left ventricular mass index (LVMI), end-diastolic left ventricular internal dimension (LVIDd), left ventricular end-diastolic posterior wall thickness (PWTd), end-diastolic interventricular septum thickness (IVSTd), E/A, and left ventricular ejection fraction (LVEF). Data was analyzed using RevMan. Twelve studies involving 433 patients were included. After RDN treatment, LVMI decreased by 13.08g/m2 (95%confidence interval [CI]: -18.38, -7.78, p < .00001), PWTd decreased by 0.60mm (95% CI: -0.87, -0.34, p < 0.00001), IVSTd decreased by 0.78mm (95% CI: -1.06, -0.49, p < .00001), and LVEF increased by 1.80% (95% CI: 0.71, 2.90, p = .001). However, there were no statistically significant improvements in LVIDd (95% CI: -1.40, 0.24, p = .17) and diastolic function (E/A) (95% CI: -0.04, 0.14, p =.28). This meta-analysis finds that RDN can improve left ventricular hypertrophy and ejection fraction in patients with RH but has no significant effect on LVIDd and diastolic function. However, more studies are warranted due to the lack of a strict control group, a limited sample size, and research heterogeneity.

Hypertension management in patients with cardiovascular comorbidities

Arterial hypertension is a leading cause of death globally. Due to ageing, the rising incidence of obesity, and socioeconomic and environmental changes, its incidence increases worldwide. Hypertension commonly coexists with Type 2 diabetes, obesity, dyslipidaemia, sedentary lifestyle, and smoking leading to risk amplification. Blood pressure lowering by lifestyle modifications and antihypertensive drugs reduce cardiovascular (CV) morbidity and mortality. Guidelines recommend dual- and triple-combination therapies using renin–angiotensin system blockers, calcium channel blockers, and/or a diuretic. Comorbidities often complicate management. New drugs such as angiotensin receptor-neprilysin inhibitors, sodium–glucose cotransporter 2 inhibitors, glucagon-like peptide-1 receptor agonists, and non-steroidal mineralocorticoid receptor antagonists improve CV and renal outcomes. Catheter-based renal denervation could offer an alternative treatment option in comorbid hypertension associated with increased sympathetic nerve activity. This review summarises the latest clinical evidence for managing hypertension with CV comorbidities.

Effects of Renal Denervation on Cardiac Structural and Functional Abnormalities in Patients with Resistant Hypertension or Diastolic Dysfunction

The aim of the present study is to systematically evaluate the impact of RDN on cardiac structure and function in patients with resistant hypertension (RH) or diastolic dysfunction. We retrieved Pubmed, Embase and Cocharane Library databases, from inception to April 1^st, 2016. Studies reporting left ventricular mass (LVMI) or left ventricular (LV) diastolic function (reflected by the ratio of mitral inflow velocity to annular relaxation velocity [E/e’]) responses to RDN were included. Two randomized controlled trials (RCTs), 3 controlled studies and 11 uncontrolled studies were finally identified. In observational studies, there was a reduction in LVMI, E/e’ and N-terminal pro B-type natriuretic peptide (BNP) at 6 months, compared with pre-RDN values. LV ejection fraction (LVEF) elevated at 6 months following RDN. In RCTs, however, no significant change in LVMI, E/e’, BNP, left atrial volume index or LVEF was observed at 12 months, compared with pharmaceutical therapy. In summary, both LV hypertrophy and cardiac function improved at 6 months after RDN. Nonetheless, current evidence failed to show that RDN was superior to intensive (optimal) drug therapy in improving cardiac remodeling and function.

High screen failure rate in patients with resistant hypertension: Findings from SYMPLICITY HTN-3

BACKGROUND

The SYMPLICITY HTN-3 trial, which randomized subjects to renal denervation (RDN) or sham control, was designed to evaluate the efficacy and safety of RDN for the treatment of resistant hypertension. Outcomes were previously reported. This retrospective analysis evaluated reasons for screen failure (SF) for randomization in the trial.

METHODS

SYMPLICITY HTN-3 enrolled subjects with office systolic blood pressure (SBP) ≥160 mmHg on stable and maximal doses of ≥3 antihypertensive medication classes. Blood pressure was measured during screening visit (SV) 1 and SV2 a minimum of 2 weeks later to ensure resistant hypertension and to exclude white-coat hypertension. We analyzed baseline characteristics and reasons for SF at each SV and changes in BP between SVs.

RESULTS

Among 1,415 patients screened, 880 (62%) did not meet criteria for randomization. Compared with randomized patients, those in the SF cohort were more likely to be older (58.7 vs. 57.4 years, P=.029), current smokers (14.5% vs. 10.7%, P=.041), and prescribed fewer antihypertensive medications (4.7 vs. 5.1, P<.001). The predominant reason for SF at SV2 was office SBP <160 mmHg despite office SBP ≥160 mmHg at SV1.

CONCLUSION

Screening patients with resistant hypertension on maximal doses of ≥3 antihypertensive drugs led to a high SF rate. Screen failures were most common at SV1 and were due to failing the office SBP entry criteria. Not meeting ambulatory SBP criteria at SV2 was a secondary reason for SF, often due to white-coat hypertension; thus, 24-hour ambulatory monitoring is important to validate resistant hypertension.

Effects of renal denervation on coronary flow reserve and forearm dilation capacity in patients with treatment-resistant hypertension. A randomized, double-blinded, sham-controlled clinical trial

BACKGROUND

Microvascular impairment is well documented in hypertension. We investigated the effect of renal sympathetic denervation (RDN) on cardiac and peripheral microvasculature in patients with treatment-resistant essential hypertension (TRH).

METHODS

A randomized, single centre, double-blinded, sham-controlled clinical trial. Fifty-eight patients with TRH (ambulatory systolic BP (ASBP) ≥ 145mmHg) despite stable treatment were randomized to RDN or SHAM. RDN was performed with the unipolar Medtronic Flex catheter. Coronary flow reserve (CFR) and coronary- and forearm minimum vascular resistance (C-Rmin and F-Rmin) were determined using transthoracic Doppler echocardiography and F-Rmin with venous occlusion plethysmography at baseline and at six-months follow-up.

RESULTS

RDN was performed with 5.3±0.2 lesions in the right renal artery and 5.4±0.2 lesions in the left. Baseline ASBP was 152±2mmHg (RDN, n=29) and 154±2mmHg (SHAM, n=29). Similar reductions in MAP were seen at follow up (-3.5±2.0 vs. -3.2±1.8, P=0.92). Baseline CFR was 2.9±0.1 (RDN) and 2.4±0.1 (SHAM), with no significant change at follow-up (0.2±0.2 vs. -0.1±0.2, P=0.57). C-Rmin was 1.9±0.3 (RDN) and 2.7±0.6 (SHAM) (mmHgmin/ml pr. 100g) and did not change significantly (0.3±0.5 vs. -0.4±0.8, P=0.48). F-Rmin was 3.6±0.2 (RDN) and 3.6±0.3 (SHAM) (mmHgmin/ml pr. 100ml tissue) and unchanged at follow-up (4.2±0.4 vs. 3.8±0.2, P=0.17). Left ventricular mass index was unchanged following RDN (-4±7 (RDN) vs. 3±5 (SHAM) (g/m²) P=0.38).

CONCLUSION

The current study does not support positive effects of RDN on microvascular impairment in TRH.

Renal sympathetic denervation for treatment of patients with heart failure: summary of the available evidence

Heart failure syndrome results from compensatory mechanisms that operate to restore - back to normal - the systemic perfusion pressure. Sympathetic overactivity plays a pivotal role in heart failure; norepinephrine contributes to maintenance of the systemic blood pressure and increasing preload. Cardiac norepinephrine spillover increases in patients with heart failure; norepinephrine exerts direct toxicity on cardiac myocytes resulting in a decrease of synthetic activity and/or viability. Importantly, cardiac norepinephrine spillover is a powerful predictor of mortality in patients with moderate to severe HF. This provided the rationale for trials that demonstrated survival benefit associated with the use of beta adrenergic blockers in heart failure with reduced ejection fraction. Nevertheless, the MOXCON trial demonstrated that rapid uptitration of moxonidine (inhibitor of central sympathetic outflow) in patients with heart failure was associated with excess mortality and morbidity, despite reduction of plasma norepinephrine. Interestingly, renal norepinephrine spillover was the only independent predictor of adverse outcome in patients with heart failure, in multivariable analysis. Recently, renal sympathetic denervation has emerged as a novel approach for control of blood pressure in patients with treatment-resistant hypertension. This article summarizes the available evidence for the effect of renal sympathetic denervation in the setting of heart failure. Key messages Experimental studies supported a beneficial effect of renal sympathetic denervation in heart failure with reduced ejection fraction. Clinical studies demonstrated improvement of symptoms, and left ventricular function. In heart failure and preserved ejection fraction, renal sympathetic denervation is associated with improvement of surrogate endpoints.

Renal Denervation to Modify Hypertension and the Heart Failure State

Sympathetic overactivation of renal afferent and efferent nerves have been implicated in the development and maintenance of several cardiovascular disease states, including resistant hypertension and heart failure with both reduced and preserved systolic function. With the development of minimally invasive catheter-based techniques, percutaneous renal denervation has become a safe and effective method of attenuating sympathetic overactivation. Percutaneous renal denervation, therefore, has the potential to modify and treat hypertension and congestive heart failure. Although future randomized controlled studies are needed to definitively prove its efficacy, renal denervation has the potential to change the way we view and treat cardiovascular disease.

Reductions of left ventricular mass and atrial size following renal denervation: a meta-analysis

BACKGROUND

Renal denervation (RDN), a novel therapy for resistant hypertension, has been shown to have an effect on cardiac remodeling in several small studies. We aimed to pool currently available data to assess the effects of RDN on left ventricular hypertrophy (LVH) and left atrial (LA) enlargement.

METHODS AND RESULTS

Two investigators independently searched PubMed, EMBASE and Cochrane Library Central Register of Controlled Trials database for studies reporting change in left ventricular mass index (LVMI) or LA size before and after RDN. Twelve publications met our pre-defined inclusion criteria. Echocardiographic data showed that RDN markedly reduced both LVMI [weighted mean difference (WMD) = -15.77 g/m(2); 95 % confidence interval (CI) -22.51 to -9.02 g/m(2)] and LA diameter [WMD = -2.48 mm; 95 % CI -4.12 to -0.83 mm] after 6 months. Data from cardiac magnetic resonance also showed a significant reduction in LVMI [WMD = -5.43 g/m(2), 95 % CI -10.01 to -0.35 g/m(2)) at 6 months. Changes in LVH and LA size at 12 months were more pronounced than those at 6 months. Meta-regression analysis failed to demonstrate a significant relationship between RDN-induced LVMI reduction and BP lowering at 6 months.

CONCLUSIONS

RDN led to significant regressions of both LVH and LA enlargement at 6 months, which were sustained at least up to 12 months.