The Preventive Effect of Cardiac Sympathetic Denervation Induced by 6-OHDA on Myocardial Ischemia–Reperfusion Injury: The Changes of lncRNA/circRNAs-miRNA-mRNA Network of the Upper Thoracic Spinal Cord in Rats

In this study, we investigated whether chemical 6-hydroxydopamine (6-OHDA) stimuli caused cardiac sympathetic denervation (SD), and we analyzed gene expression profiles to determine the changes in the lncRNA/circRNAs-miRNA-mRNA network in the affected spinal cord segments to identify putative target genes and molecular pathways in rats with myocardial ischemia–reperfusion injury (MIRI). Our results showed that cardiac sympathetic denervation induced by 6-OHDA alleviated MIRI. Compared with the ischemia reperfusion (IR, MIRI model) group, there were 148 upregulated and 51 downregulated mRNAs, 165 upregulated and 168 downregulated lncRNAs, 70 upregulated and 52 downregulated circRNAs, and 12 upregulated and 11 downregulated miRNAs in the upper thoracic spinal cord of the SD-IR group. Furthermore, we found that the differential genes related to cellular components were mainly enriched in extracellular and cortical cytoskeleton, and molecular functions were mainly enriched in chemokine activity. Pathway analysis showed that the differentially expressed genes were mainly related to the interaction of cytokines and cytokine receptors, sodium ion reabsorption, cysteine and methionine metabolism, mucoglycan biosynthesis, cGMP-PKG signaling pathway, and MAPK signaling pathway. In conclusion, the lncRNA/circRNAs-miRNA-mRNA networks in the upper thoracic spinal cord play an important role in the preventive effect of cardiac sympathetic denervation induced by 6-OHDA on MIRI, which offers new insights into the pathogenesis of MIRI and provides new targets for MIRI.

sST2 Predicts Short Term Therapy Success in Patients with Therapy Resistant Hypertension after Renal Sympathetic Denervation

Background: Renal sympathetic denervation (RSD) has provided promising data in its ability to treat therapy resistant arterial hypertension. The effect of RSD on sST-2, a promising biomarker for risk stratification in cardiovascular diseases, has so far not been systematically studied. Methods: We evaluated serum levels of sST-2 and clinical parameter including left ventricular mass (LVM) in 54 patients with resistant hypertension (RH) undergoing bilateral RSD at baseline as well as at one and/or three months. Results: After RSD, mean office blood pressure showed a significant decrease after one month (p < 0.001). On echocardiography a reduction of LVM was observed at three months (p < 0.01). This was accompanied by a significant decrease of sST-2 levels at three months (sST-2 baseline: 6310.1 ± 3246.0 pg/mL vs. sST-2 three months: 4703.8 ± 1585.9 pg/mL, p = 0.048). Furthermore, baseline sST-2 levels were positively correlated with systolic blood pressure at one month (r = 0.514, p < 0.01) but not three months, indicating a potential predictive value of sST-2 for early intervention success. Conclusion: In patients with RH, RSD is associated with a significant decrease of sST-2 levels after three months, indicating sST-2 to be involved in remodeling processes after RSD. Furthermore, lower sST-2 levels at baseline might be a potential predictor of early intervention success of RSD.

Comparison of Long‐Term Outcomes for Responders Versus Non‐Responders Following Renal Denervation in Resistant Hypertension

Background Recent trial results support the efficacy of renal sympathetic denervation in lowering blood pressure (BP). While BP reduction in general is associated with a clinically meaningful reduction in cardiovascular events and mortality, such a relationship has not been described for patients undergoing renal sympathetic denervation. Methods and Results Clinical events were assessed in patients who underwent renal sympathetic denervation at our center using telephone‐ and clinical follow‐up, interviews with general practitioners, as well as review of hospital databases. Event rates were compared between BP responders (≥5 mm Hg 24‐hour ambulatory BP reduction) and non‐responders; 296 patients were included. Compared with baseline, 24‐hour systolic ambulatory BP was reduced by 8.3±12.2 mm Hg and diastolic BP by 4.8±7.0 mm Hg ( P <0.001 for both) after 3 months. One hundred eighty patients were classified as BP responders and 116 as non‐responders. During a median follow‐up time of 48 months, significantly less major adverse cardiovascular events (cardiovascular death, stroke, myocardial infarction, critical limb ischemia, renal failure) occurred in responders than in non‐responders (22 versus 23 events, hazard ratio [HR], 0.53 [95% CI, 0.28 to 0.97], P =0.041). This was consistent after adjustment for potential confounders as well as confirmed by propensity‐score matching. A proportional relationship was found between BP reduction after 3 months and frequency of major adverse cardiovascular events (HR, 0.75 [95% CI, 0.58 to 0.97] per 10 mm Hg 24‐hour systolic ambulatory BP reduction). Conclusions Based on these observational data, blood pressure response to renal sympathetic denervation is associated with improved long‐term clinical outcome.

Endovascular renal sympathetic denervation to improve heart failure with reduced ejection fraction: the IMPROVE-HF-I study

Introduction The aim of the present study was to assess the safety and efficacy of renal sympathetic denervation (RDN) in patients with heart failure with reduced ejection fraction (HFrEF). Methods We randomly assigned 50 patients with a left ventricular ejection fraction (LVEF) ≤ 35% and NYHA class ≥ II, in a 1:1 ratio, to either RDN and optimal medical therapy (OMT) or OMT alone. The primary safety endpoint was the occurrence of a combined endpoint of cardiovascular death, rehospitalisation for heart failure, and acute kidney injury at 6 months. The primary efficacy endpoint was the change in iodine-123 meta-iodobenzylguanidine (123I‑MIBG) heart-to-mediastinum ratio (HMR) at 6 months. Results Mean age was 60 ± 9 years, 86% was male and mean LVEF was 33 ± 8%. At 6 months, the primary safety endpoint occurred in 8.3% vs 8.0% in the RDN and OMT groups, respectively (p = 0.97). At 6 months, the mean change in late HMR was −0.02 (95% CI: −0.08 to 0.12) in the RDN group, versus −0.02 (95% CI: −0.09 to 0.12) in the OMT group (p = 0.95) whereas the mean change in washout rate was 2.34 (95% CI: −6.35 to 1.67) in the RDN group versus −2.59 (95% CI: −1.61 to 6.79) in the OMT group (p-value 0.09). Conclusion RDN with the Vessix system in patients with HFrEF was safe, but did not result in significant changes in cardiac sympathetic nerve activity at 6 months as measured using 123I‑MIBG.