Effects of baroreflex activation therapy on cardiac function and morphology.

AIMS: Arterial hypertension (aHTN) plays a fundamental role in the pathogenesis and prognosis of heart failure with preserved ejection fraction (HFpEF). The risk of heart failure increases with therapy-resistant arterial hypertension (trHTN), defined as inadequate blood pressure (BP) control ≥140/90 mmHg despite taking ≥3 antihypertensive medications including a diuretic. This study investigates the effects of the BP lowering baroreflex activation therapy (BAT) on cardiac function and morphology in patients with trHTN with and without HFpEF. METHODS: Sixty-four consecutive patients who had been diagnosed with trHTN and received BAT implantation between 2012 and 2016 were prospectively observed. Office BP, electrocardiographic and echocardiographic data were collected before and after BAT implantation. RESULTS: Mean patients' age was 59.1 years, 46.9% were male, and mean body mass index (BMI) was 33.2 kg/m2. The prevalence of diabetes mellitus was 38.8%, atrial fibrillation was 12.2%, and chronic kidney disease (CKD) stage ≥3 was 40.8%. Twenty-eight patients had trHTN with HFpEF, and 21 patients had trHTN without HFpEF. Patients with HFpEF were significantly older (64.7 vs. 51.6 years, P < 0.0001), had a lower BMI (30.0 vs. 37.2 kg/m2, P < 0.0001), and suffered more often from CKD-stage ≥3 (64 vs. 20%, P = 0.0032). After BAT implantation, mean office BP dropped in patients with and without HFpEF (from 169 ± 5/86 ± 4 to 143 ± 4/77 ± 3 mmHg [P = 0.0019 for systolic BP and 0.0403 for diastolic BP] and from 170 ± 5/95 ± 4 to 149 ± 6/88 ± 5 mmHg [P = 0.0019 for systolic BP and 0.0763 for diastolic BP]), while a significant reduction of the intake of calcium-antagonists, α2-agonists and direct vasodilators, as well as a decrease in average dosage of ACE-inhibitors and α2-agonists could be seen. Within the study population, a decrease in heart rate from 74 ± 2 to 67 ± 2 min-1 (P = 0.0062) and lengthening of QRS-time from 96 ± 3 to 106 ± 4 ms (P = 0.0027) and QTc-duration from 422 ± 5 to 432 ± 5 ms (P = 0.0184) were detectable. The PQ duration was virtually unchanged. In patients without HF, no significant changes of echocardiographic parameters could be seen. In patients with HFpEF, posterior wall diameter decreased significantly from 14.0 ± 0.5 to 12.7 ± 0.3 mm (P = 0.0125), left ventricular mass (LVM) declined from 278.1 ± 15.8 to 243.9 ± 13.4 g (P = 0.0203), and e' lateral increased from 8.2 ± 0.4 to 9.0 ± 0.4 cm/s (P = 0.0471). CONCLUSIONS: BAT reduced systolic and diastolic BP and was associated with morphological and functional improvement of HFpEF.

Urinary Dickkopf-3 (DKK3) Is Associated with Greater eGFR Loss in Patients with Resistant Hypertension.

Patients with resistant hypertension (HTN) demonstrate an increased risk of chronic kidney disease and progression to end-stage renal disease; however, the individual course of progression is hard to predict. Assessing the stress-induced, urinary glycoprotein Dickkopf-3 (uDKK3) may indicate ongoing renal damage and consecutive estimated glomerular filtration rate (eGFR) decline. The present study aimed to determine the association between uDKK3 levels and further eGFR changes in patients with resistant HTN. In total, 31 patients with resistant HTN were included. Blood pressure and renal function were measured at baseline and up to 24 months after (at months 12 and 24). uDKK3 levels were determined exclusively from the first available spot urine sample at baseline or up to a period of 6 months after, using a commercial ELISA kit. Distinctions between different patient groups were analyzed using the unpaired t-test or Mann-Whitney test. Correlation analysis was performed using Spearman's correlation. The median uDKK3 level was 303 (interquartile range (IQR) 150-865) pg/mg creatinine. Patients were divided into those with high and low eGFR loss (≥3 vs. <3 mL/min/1.73 m²/year). Patients with high eGFR loss showed a significantly higher median baseline uDKK3 level (646 (IQR 249-2555) (n = 13) vs. 180 (IQR 123-365) pg/mg creatinine (n = 18), p = 0.0412 (Mann-Whitney U)). Alternatively, patients could be classified into those with high and low uDKK3 levels (≥400 vs. <400 pg/mg creatinine). Patients with high uDKK3 levels showed significantly higher eGFR loss (-6.4 ± 4.7 (n = 11) vs. 0.0 ± 7.6 mL/min/1.73 m2/year (n = 20), p = 0.0172 (2-sided, independent t-test)). Within the entire cohort, there was a significant correlation between the uDKK3 levels and change in eGFR at the latest follow-up (Spearman's r = -0.3714, p = 0.0397). In patients with resistant HTN, high levels of uDKK3 are associated with higher eGFR loss up to 24 months later.

Effect of baroreflex activation therapy on dipping pattern in patients with resistant hypertension.

A relevant number of patients with resistant hypertension do not achieve blood pressure (BP) dipping during nighttime. This inadequate nocturnal BP reduction is associated with elevated cardiovascular risks. The aim of this study was to evaluate whether a nighttime intensification of BAT might improve nocturnal BP dipping. In this prospective observational study, non-dippers treated with BAT for at least 6 months were included. BAT programming was modified in a two-step intensification of nighttime stimulation at baseline and week 6. Twenty-four hours ambulatory BP (ABP) was measured at inclusion and after 3 months. A number of 24 patients with non- or inverted dipping pattern, treated with BAT for a median of 44 months (IQR 25-52) were included. At baseline of the study, patients were 66 ± 9 years old, had a BMI of 33 ± 6 kg/m2 , showed an office BP of 135 ± 22/72 ± 10 mmHg, and took a median number of antihypertensives of 6 (IQR 4-9). Nighttime stimulation of BAT was adapted by an intensification of pulse width from 237 ± 161 to 267 ± 170 µs (p = .003) while frequency (p = .10) and amplitude (p = .95) remained unchanged. Uptitration of BAT programming resulted in an increase of systolic dipping from 2 ± 6 to 6 ± 8% (p = .03) accompanied with a significant improvement of dipping pattern (p = .02). Twenty four hours ABP, day- and nighttime ABP remained unchanged. Programming of an intensified nighttime BAT interval improved dipping profile in patients treated with BAT, while the overall 24 h ABP did not change. Whether the improved dipping response contributes to a reduction of cardiovascular risk beyond the BP-lowering effects of BAT, however, remains to be shown.

Impact of medication adherence on the efficacy of Baroreflex activation therapy.

Therapy adherence significantly determines the success of antihypertensive therapy, especially in patients with resistant hypertension. Our study investigates the impact of drug adherence on the efficacy of Baroreflex-activation-therapy (BAT). In this retrospective analysis, the authors measured blood pressure (BP) and antihypertensive medication adherence (by gas chromatography-mass spectrometry [GC-MS] urine analysis) before and 6 months after BAT initiation. Adherence was defined as detection of ≥80% intake of prescribed medication at the time of follow-up. Response to BAT was defined as BP drop ≥5 mmHg in systolic 24 h-ambulatory BP (ABP) after 6 months. Overall patients (n = 38) median medication adherence was low, but rose from 60% (IQR 25%-100%) to 75% (IQR 38%-100%; p = .0194). After 6 months of BAT, mean systolic and diastolic office BP (-21 ± 25 mmHg and -9 ± 15 mmHg; p < .0001 and .0004) as well as 24 h-ABP dropped significantly (-9 ± 17 mmHg and -5 ± 12 mmHg; p = .0049 and .0280). After 6 months of BAT, 21 patients (60%) could be classified as responders. There was neither significant difference in mean office systolic (-21 ± 23 mmHg vs. -21 ± 28 mmHg; p = .9581) nor in 24 h-systolic ABP decrease (-11 ± 19 mmHg vs. -7 ± 15 mmHg; p = .4450) comparing adherent and non-adherent patients. Whereas Antihypertensive Therapeutic Index (ATI) was unchanged in non-responders, it significantly decreased in responders (from 50 ± 16 to 46 ± 16; p = .0477). These data are the first to show that BAT-initiation leads to a clear BP reduction independently of patients´ medication adherence. Response to BAT is associated with a significant lowering of ATI, which might contribute to an underestimation of BAT efficacy.

Cytokine adsorption therapy in lymphoma-associated hemophagocytic lymphohistiocytosis and allogeneic stem cell transplantation.

Lymphoma-associated Hemophagocytic lymphohistiocytosis (HLH) represents a severe complication of disease progression, mediated through cytokine release from the lymphoma cells. Cytokine adsorption may contribute as a supportive treatment to stabilize organ function by reduction of cytokine levels. So far, no experiences of cytokine adsorption and simultaneous stem cell transplantation were published. We report the case of a patient with aggressive lymphoma secondary to chronic lymphocytic leukemia with rapidly progressive HLH (Richter's transformation) upon conditioning chemotherapy prior to allogeneic stem cell transplantation (ASCT). Continuous hemodiafiltration was initiated in the treatment of shock with acute renal failure, lactacidosis and need for high-dose catecholamine therapy, integrating an additional cytokine-adsorbing filter (CytoSorb®) to reduce cytokine levels. This was followed by scheduled allogenic stem cell transplantation. We observed a marked decrease in interleukin-6 plasma levels, associated with a reduced need for vasopressor therapy and organ function stabilization. Hematopoietic engraftment was present at day 14 post-ASCT, leading to disease-free discharge at day 100 post-transplantation. Cytokine adsorption may serve as a safe adjunct to HLH/sepsis treatment during allogeneic stem cell transplantation. Clinical studies are required to make future treatment recommendations.

Urine proteomics for prediction of disease progression in patients with IgA nephropathy.

BACKGROUND: Risk of kidney function decline in immunoglobulin A (IgA) nephropathy (IgAN) is significant and may not be predicted by available clinical and histological tools. To serve this unmet need, we aimed at developing a urinary biomarker-based algorithm that predicts rapid disease progression in IgAN, thus enabling a personalized risk stratification. METHODS: In this multicentre study, urine samples were collected in 209 patients with biopsy-proven IgAN. Progression was defined by tertiles of the annual change of estimated glomerular filtration rate (eGFR) during follow-up. Urine samples were analysed using capillary electrophoresis coupled mass spectrometry. The area under the receiver operating characteristic curve (AUC) was used to evaluate the risk prediction models. RESULTS: Of the 209 patients, 64% were male. Mean age was 42 years, mean eGFR was 63 mL/min/1.73 m2 and median proteinuria was 1.2 g/day. We identified 237 urine peptides showing significant difference in abundance according to the tertile of eGFR change. These included fragments of apolipoprotein C-III, alpha-1 antitrypsin, different collagens, fibrinogen alpha and beta, titin, haemoglobin subunits, sodium/potassium-transporting ATPase subunit gamma, uromodulin, mucin-2, fractalkine, polymeric Ig receptor and insulin. An algorithm based on these protein fragments (IgAN237) showed a significant added value for the prediction of IgAN progression [AUC 0.89; 95% confidence interval (CI) 0.83-0.95], as compared with the clinical parameters (age, gender, proteinuria, eGFR and mean arterial pressure) alone (0.72; 95% CI 0.64-0.81). CONCLUSIONS: A urinary peptide classifier predicts progressive loss of kidney function in patients with IgAN significantly better than clinical parameters alone.

Syndecan-4 as a Marker of Endothelial Dysfunction in Patients with Resistant Hypertension.

(1) Background: Arterial hypertension (HTN) is one of the most relevant cardiovascular risk factors. Nowadays multiple pharmaceutical treatment options exist with novel interventional methods (e.g., baroreflex activation therapy (BAT)) as a last resort to treat patients with resistant HTN. Although pathophysiology behind resistant HTN is still not fully understood. There is evidence that selected biomarkers may be involved in the pathophysiology of HTN. (2) Methods: We investigated serum SDC4-levels in patients suffering from resistant HTN before and 6 months after BAT implantation. We collected 19 blood samples from patients with resistant HTN and blood pressure above target and measured serum SDC4-levels. (3) Results: Our results showed high serum SDC4-levels in patients with resistant HTN as compared to a healthy population. Patients with both, resistant HTN and diabetes mellitus type II, demonstrated higher serum SDC4-levels. ß-blockers had lowering effects on serum SDC4-levels, whereas calcium channel blockers were associated with higher levels of serum SDC4. BAT implantation did not lead to a significant difference in serum SDC4-levels after 6 months of therapy. (4) Conclusion: Based on our results we propose SDC4 is elevated in patients suffering from resistant HTN. Thus, SDC4 might be a potential marker for endothelial dysfunction in patients with resistant hypertension.

Plasma Exchange or Immunoadsorption in Demyelinating Diseases: A Meta-Analysis.

Multiple sclerosis (MS) is an inflammatory disease mainly affecting the central nervous system. In MS, abnormal immune mechanisms induce acute inflammation, demyelination, axonal loss, and the formation of central nervous system plaques. The long-term treatment involves options to modify the disease progression, whereas the treatment for the acute relapse has its focus in the administration of high-dose intravenous methylprednisolone (up to 1000 mg daily) over a period of three to five days as a first step. If symptoms of the acute relapse persist, it is defined as glucocorticosteroid-unresponsive, and immunomodulation by apheresis is recommended. However, several national and international guidelines have no uniform recommendations on using plasma exchange (PE) nor immunoadsorption (IA) in this case. A systematic review and meta-analysis was conducted, including observational studies or randomized controlled trials that investigated the effect of PE or IA on different courses of MS and neuromyelitis optica (NMO). One thousand, three hundred and eighty-three patients were included in the evaluation. Therapy response in relapsing-remitting MS and clinically isolated syndrome was 76.6% (95%CI 63.7-89.8%) in PE- and 80.6% (95%CI 69.3-91.8%) in IA-treated patients. Based on the recent literature, PE and IA may be considered as equal treatment possibilities in patients suffering from acute, glucocorticosteroid-unresponsive MS relapses.

Long-term effects of baroreflex activation therapy: 2-year follow-up data of the BAT Neo system.

OBJECTIVE: Baroreflex activation therapy (BAT) reduces office blood pressure (BP) in patients with resistant hypertension (HTN). Whereas sustained effects from the BAT Rheos device have already been reported, no long-term data on 24-h ambulatory BP (ABP) are currently available for the unilateral BAT Neo device. METHODS: Patients treated with the BAT neo device for resistant hypertension were prospectively included into this observational study. Office and ABP measurements were performed before BAT implantation as well as 6, 12 and 24 months after initiation of BAT. RESULTS: A total of 60 patients with resistant HTN (office BP 172 ± 25/90 ± 17 mmHg, 24-h ABP 150 ± 16/80 ± 12 mmHg, median of antihypertensive drugs 7 (IQR 6-8)) were included. After 24 months, there was a significant reduction of - 25 ± 33/- 9 ± 18 mmHg (n = 50, both p < 0.01) in office BP and - 8 ± 23/- 5 ± 13 mmHg (n = 46, both p = 0.02) in 24-h ABP, while the number of antihypertensive medications was reduced to a median of 5 (4-6) drugs (p < 0.01). Patients with isolated systolic HTN (ISH) experienced a BP-lowering effect in office BP, but not in ABPM at month 24. Using unadjusted BP values, BAT seems to be more effective in combined hypertension (CH) than in ISH. After adjustment for baseline BP values, there was no significant difference in BP reduction between ISH and CH patients. Ambulatory SBP at baseline was the only independent correlate of BP response at month 24. CONCLUSION: BAT reduced office BP and improved relevant parameters of ABP, which is associated with a high cardiovascular risk, in patients with resistant HTN, whereas, after adjustment for baseline BP, BP reduction was not different in patients with CH compared with patients with ISH. However, randomized controlled trials are needed to confirm the effects of BAT on 24-h ABP.

Risk factors for catheter-related infections in patients receiving permanent dialysis catheter.

BACKGROUND: Due to rising vascular comorbidities of patients undergoing dialysis, the prevalence of permanent hemodialysis catheters as hemodialysis access is increasing. However, infection is a major complication of these catheters. Therefore, identification of potential predicting risk factors leading to early infection related complications is valuable, in particular the significance the CRP (C-reactive protein)-value is of interest. METHODS: In this retrospective study 151 permanent hemodialysis catheters implanted in 130 patients were examined. The following data were collected at the time of catheter implantation: CRP-value, history of catheter-related infection, microbiological status, immunosuppression and diabetes mellitus. The primary outcomes were recorded over the 3 months following the implantation: catheter-related infection, days of hospital stay and death. Catheter removal or revision, rehospitalization and use of antibiotics were identified as secondary outcomes. RESULTS: We identified a total of 27 (17.9%) infections (systemic infection: 2.26 episodes/ 1000 catheter days, local infection: 0.6 episodes/ 1000 catheter days). The development of an infection was independent of the CRP-value (p = 0.66) as well as the presence of diabetes mellitus (p = 0.64) or immunosuppression (p = 0.71). Univariate analysis revealed that infection was more frequent in patients with MRSA-carriage (p < 0.001), in case of previous catheter-related infection (p < 0.05) and of bacteremia or bacteriuria in the period of 3 months before catheter implantation (p < 0.001). Catheter removal or revision (p = 0.002), rehospitalization (p = 0.001) and use of antibiotics (p = 0.02) were also more often observed in patients with MRSA-carriage. CONCLUSIONS: The CRP-value at the time of implantation of a permanent hemodialysis catheter is not associated with the development of early catheter related infections, but an individual history of catheter-related infection, MRSA-carriage and bacteremia or bacteriuria in the period of 3 months prior to catheter implantation are significant risk factors.

Effect of baroreflex activation therapy on renal sodium excretion in patients with resistant hypertension.

OBJECTIVE: Activation of the sympathetic nervous system increases sodium retention in resistant hypertension. Baroreflex activation therapy (BAT) is an interventional method to reduce sympathetic overactivity in patients with resistant hypertension. This study aimed to assess the effect of BAT on urinary sodium excretion. METHODS: From 2012 to 2015, consecutive patients with resistant hypertension and blood pressure (BP) above target despite polypharmacy strategies were consecutively included in this observational study. BAT was provided with the individual adaption of programmed parameters over the first months. 24-h urinary sodium excretion (UNa) was estimated at baseline and after 6 months using the Kawasaki formula in patients undergoing BAT. Additionally, the fractional sodium excretion, plasma renin activity, and aldosterone levels were assessed. RESULTS: Forty-two patients completed the 6-month follow-up period. Office systolic and ambulatory 24-h systolic BP at baseline were 169 ± 27 mmHg and 148 ± 16 mmHg despite a median intake of 7(3-9) antihypertensive drugs. After 6 months of BAT, systolic office BP decreased to 150 ± 29 mmHg (p < 0.01), 24-h systolic BP to 142 ± 22 mmHg (p = 0.04) and 24-h UNa increased by 37% compared to baseline (128 ± 66 vs. 155 ± 83 mmol/day, p < 0.01). These findings were accompanied by a significant increase in fractional sodium excretion (0.74% [0.43-1.47] to 0.92% [0.61-1.92]; p = 0.02). However, in contrast to the significant BP reduction, eGFR, plasma sodium, renin activity and aldosterone levels did not change during BAT. The increase in sodium excretion was correlated with the change in eGFR (r = 0.371; p = 0.015). CONCLUSION: The present study revealed a significant increase of estimated 24-h UNa which may contribute to the long-term BP-lowering effects of this interventional method.

Immunoadsorption or plasma exchange in steroid-refractory multiple sclerosis and neuromyelitis optica.

BACKGROUND: Plasma exchange (PE) and immunoadsorption (IA) are alternative treatments of steroid-refractory relapses of multiple sclerosis (MS) or neuromyelitis optica (NMO). METHODS: Adverse events and neurological follow-ups in 127 MS- (62 PE, 65 IA) and 13 NMO- (11 PE, 2 IA) patients were retrospectively analyzed. Response was defined by improvements in either expanded disability status scale (EDSS) by at least 1.0 or visual acuity (VA) to 0.5, confirmed after 3 and/or 6 months. RESULTS: Hundred and forty patients were included in safety analysis, 102 patients provided sufficient neurological follow-up-data. There were no significant differences between IA and PE in side effects (3.9% vs 3.6%, P = .96) or response-rate (P = .65). Responders showed significant lower age (P = .02) and earlier apheresis-initiation (P = .01). Subgroup-analysis confirmed significant lower age in patients with relapsing-remitting MS (RRMS) /clinical isolated syndrome (CIS). CONCLUSION: IA and PE seem equally safe and effective in steroid-resistant MS- or NMO-relapses. Early apheresis and low patient age are additional prognostic factors.

Direct assessment of adherence and drug interactions in patients with hypertensive crisis-A cross-sectional study in the Emergency Department.

Though drug adherence is supposed to be low in hypertensive crisis (HTN-C), there are no data available from direct adherence assessments. The aim of the present study was to evaluate adherence to prescribed antihypertensives and potential interactions of concomitant drugs and foods with prescribed antihypertensives in patients with HTN-C by a direct evaluation via biochemical urine analysis. In the present cross-sectional study, 100 patients with HTN-C, admitted to the emergency department (ED), were included. A biochemical urine analysis using gas chromatography-tandem mass spectrometry was performed. Out of 100 patients, 86 received antihypertensives. Urine analyses could be evaluated unambiguously in 62 patients. In 15 of these 62 patients (24%), a nonadherence could be demonstrated, and in 21 patients (34%), a partial nonadherence could be demonstrated. Patients with nonadherence or partial nonadherence showed a longer hypertension history (15[5-22] vs 10[3-15] years, P = 0.04) were prescribed more general medication (number 7.1 ± 3.4 vs 3.4 ± 1.8; P < 0.01) as well as antihypertensive drugs (number 2.8 ± 1.1 vs 1.5 ± 0.7, P < 0.01). A potential BP-raising trigger by medications or food interaction was frequently detectable, predominantly with nonsteroidal anti-inflammatory drugs (NSAIDs; n = 38), glucocorticoids (n = 8), antidepressants (n = 10), and licorice (n = 10). Nonadherence and partial nonadherence to prescribed antihypertensives might play a crucial role for the occurrence of HTN-C. However, further case-controlled studies are needed to confirm the present findings. Ingestion of concurrent over-the-counter drugs such as NSAIDs but also prescribed drugs as well as aliments may lead to critical BP elevation. In order to prevent HTN-C, the present findings emphasize the importance for clinicians to pay attention to the issue of adherence and co-medication.

Kidney protective effects of baroreflex activation therapy in patients with resistant hypertension.

Baroreflex activation therapy (BAT) is approved for the treatment of resistant hypertension. In addition to blood pressure (BP) reduction, pilot studies suggested several organoprotective effects of BAT. Thirty-two patients with resistant hypertension were prospectively treated with BAT. Besides office BP and 24-hour ambulatory BP (ABP) measurements, detection of a urinary proteome-based classifier (CKD273), which has been shown to predict chronic kidney disease (CKD) progression, was carried out at baseline and after 6 months of BAT. Office BP significantly decreased from 170 ± 25/90 ± 18 to 149 ± 29/82 ± 18 mm Hg. Analysis of CKD273 score and eGFR with CKD-EPI equation at baseline revealed strong correlation (r = 0.568, P < 0.001). After 6 months of BAT, there was no significant change in CKD273 score (-0.061 [95% CI: -0.262 to 0.140], P = 0.601). However, by stratification of the data regarding ABP response, there was a statistically significant (P = 0.0113) reduction in the CKD273 score from a mean of 0.161 [95% CI: -0.093 to 0.414] to -0.346 [95% CI: -0.632 to -0.060] after BAT in patients with systolic ABP decrease of ≥5 mm Hg. These data emphasized potential nephroprotective effects of BAT in patients with sufficient BP response.

Difference between renal and splenic resistive index as a novel criterion in Doppler evaluation of renal artery stenosis.

Detection of renal artery stenosis (RAS) using Doppler is difficult to evaluate, particularly under conditions such as bilateral RAS or difficultly accessible renal arteries (RA). The objective of the present study was to assess the utility of splenic arterial compared to renal flow as an additional parameter in the Doppler evaluation of RAS. The difference between the resistive indices (RI) determined in renal and splenic parenchymal arteries (ΔRIK-S ) was evaluated in 181 hypertensive subjects without any evidence of RAS. Subsequently 47 RA in 24 patients with suspected RAS were angiographically assessed. A ΔRIK-S of 0.055 (median) was determined in the population without any evidence of RAS similar to RA with angiographically excluded stenosis (ΔRIK-S 0.068). In contrast, in angiographic proven RAS, ΔRIK-S was significantly lower (-0.050; P < .005). The assessment of the ΔRIK-S , proved to be an easily feasible parameter, which improves the diagnostic accuracy in the detection of RAS.

Baroreceptors in the carotid and hypertension-systematic review and meta-analysis of the effects of baroreflex activation therapy on blood pressure.

Activation of baroreceptors in the carotid modulates the autonomic nervous system. Baroreflex activation therapy (BAT), which activates baroreceptors in the carotid, has become available in the treatment of resistant hypertension. Besides this, a carotid implant modulating baroreceptors as well as pharmacological modulation of carotid bodies were quite recently presented. This review will underscore currently available and promising approaches that activate baroreceptors in the carotid, and thereby contribute to beneficial effects in patients with arterial hypertension, and discusses potential organoprotective BAT effects beyond blood pressure (BP) reduction. A systematic review and meta-analysis was conducted including observational studies or randomized controlled trials that investigated the effect of BAT on BP in resistant hypertension. Nine studies, seven observational and two randomized, with a total of 444 patients, were included in the evaluation. Analysing the longest follow-up visit from the different studies, there was a significant reduction of systolic BP after BAT of -36 mmHg [95% confidence interval (CI) -42 to -30 mmHg]. Separate meta-analysis of the short-term (1-6 months) and long-term effects (≥12 months) revealed a reduction of -21 mmHg (95% CI -26 to -17 mmHg) and -38 mmHg (95% CI -46 to -30 mmHg), respectively. There are promising data both in the experimental and the clinical application for BAT. Though the present meta-analysis suggests beneficial effects of BAT on BP, the results must be interpreted extremely carefully. Considering that evidence from controlled trials is very limited, it is evident that there is a strong need for further investigation.

FABP1 and FABP3 Have High Predictive Values for Renal Replacement Therapy in Patients with Acute Kidney Injury.

BACKGROUND/AIMS: Early initiation of renal replacement therapy (RRT) is recommended in order to improve the clinical outcome of patients who develop an acute kidney injury (AKI). However, markers that guide an early RRT initiation do not really exist currently. METHODS: Urine and serum samples were prospectively collected from 120 AKI patients. Depending on the necessity of initiating RRT, patients were divided into 2 different groups: dialysis (n = 52) and non-dialysis (n = 68). RESULTS: Comparative urinary proteomic analyses identified 4 different proteins (fatty acid binding proteins 1 and 3 (FABP1 and FABP3), ß-2-microglobulin (B2M), cystatin-M (CST6)) that discriminate AKI patients with high risk for RRT. Western blot analysis confirmed the proteomics data for FABP1 and FABP3 but not for B2M and CST6. Validation analysis confirmed that the FABP1 and FABP3 fulfilled the requirement of functioning as markers for AKI patients with risk to dialysis (p < 0.001). CONCLUSION: The release of high amounts of FABP1 and FABP3 in urine of AKI patients could serve as a diagnostic/prognosis marker for RRT initiation in these patients.

Baroreflex activation therapy in patients with prior renal denervation.

BACKGROUND: Both baroreflex activation therapy (BAT) and renal denervation modulate sympathetic activity. The aim of this study was to systematically investigate whether additive modulation of autonomic nervous system by BAT lowers blood pressure (BP) in patients who still suffer from uncontrolled resistant hypertension despite prior renal denervation. METHODS: From 2012 to January 2015, patients treated with BAT for uncontrolled resistant hypertension, who prior received renal denervation were consecutively analyzed in four German centers for hypertension. Analyses of office BP, 24-h ambulatory BP, central hemodynamics, parameters of renal function were performed. RESULTS: A total of 28 patients, who underwent renal denervation at least 5 months before and still suffer from uncontrolled BP, were subsequently treated with BAT. The office SBP decreased from 182 ±â€Š28 to 163 ±â€Š27 mmHg (P < 0.01) with a responder rate of 68% (office SBP reduction ≥10 mmHg) at month 6, whereas the number of prescribed antihypertensive drug classes remained unchanged (6.2 ±â€Š1.5 vs. 6.0 ±â€Š1.7, P = 0.30). Serum creatinine, estimated glomerular filtration rate and cystatin C remained stable (P = 1.00, P = 0.41 and P = 0.22, respectively), whereas albuminuria was significantly reduced by a median of -29% (P = 0.02). Central SBP (-15 ±â€Š24 mmHg, P = 0.047) and end systolic pressure (-14 ±â€Š20 mmHg, P = 0.03) were significantly reduced. CONCLUSION: The present data demonstrate that BAT may exert BP-lowering as well as antiproteinuric effects in patients with prior renal denervation. However, precise evaluation of BAT effects in patients with prior renal denervation will need randomized controlled trials using sham procedures.

Effects of Baroreflex Activation Therapy on Ambulatory Blood Pressure in Patients With Resistant Hypertension.

Baroreflex activation therapy (BAT) has been demonstrated to decrease office blood pressure (BP) in the randomized, double-blind Rheos trial. There are limited data on 24-hour BP changes measured by ambulatory BP measurements (ABPMs) using the first generation rheos BAT system suggesting a significant reduction but there are no information about the effect of the currently used, unilateral BAT neo device on ABPM. Patients treated with the BAT neo device for uncontrolled resistant hypertension were prospectively included into this study. ABPM was performed before BAT implantation and 6 months after initiation of BAT. A total of 51 patients were included into this study, 7 dropped out from analysis because of missing or insufficient follow-up. After 6 months, 24-hour ambulatory systolic (from 148 ± 17 mm Hg to 140 ± 23 mm Hg, P<0.01), diastolic (from 82 ± 13 mm Hg to 77 ± 15 mm Hg, P<0.01), day- and night-time systolic and diastolic BP (all P ≤ 0.01) significantly decreased while the number of prescribed antihypertensive classes could be reduced from 6.5 ± 1.5 to 6.0 ± 1.8 (P=0.03). Heart rate and pulse pressure remained unchanged. BAT was equally effective in reducing ambulatory BP in all subgroups of patients. This is the first study demonstrating a significant BP reduction in ABPM in patients undergoing chronically stimulation of the carotid sinus using the BAT neo device. About that BAT-reduced office BP and improved relevant aspects of ABPM, BAT might be considered as a new therapeutic option to reduce cardiovascular risk in patients with resistant hypertension. Randomized controlled trials are needed to evaluate BAT effects on ABPM in patients with resistant hypertension accurately.

Baroreflex activation therapy in patients with end-stage renal failure: proof of concept.

BACKGROUND: Resistant arterial hypertension and chronic kidney disease (CKD) are interlinked via sympathetic overactivity. Baroreflex activation therapy (BAT) is a well tolerated therapy, which has been shown to reduce BP in patients with resistant hypertension. The effects of BAT in patients with resistant hypertension and end stage renal disease have not been reported. METHOD AND RESULTS: We retrospectively analyzed procedural effectiveness and safety in seven CKD stage 5D patients with resistant hypertension who underwent BAT. One year after activation, office SBP decreased significantly from 194 ±â€Š28 to 137 ±â€Š16 mmHg (P < 0.01). Ambulatory SBP showed a trend to be decreased from 167 ±â€Š30 to 137 ±â€Š24 mmHg (P = 0.17), whereas the median number of prescribed antihypertensive classes decreased from 5 (4-9) to 3 (1-4) (P = 0.01). Intraoperative drop of SBP was -34.3 ±â€Š34.4 mmHg (P = 0.04). With respect to adverse events there were minor side-effects (mainly paresthesia and dysphagia) reported in our patients, which occurred according to treatment intensity and modality. CONCLUSION: BAT is an effective and well tolerated intervention to reduce BP in patients suffering from end-stage renal disease and resistant hypertension. Therefore, BAT might contribute to a reduction of cardiovascular events in those high-risk patients.