Characterisation and distribution of human coronary artery innervation.

BACKGROUND: A detailed understanding of the sympathetic innervation of coronary arteries is relevant to facilitate the development of novel treatment approaches. AIMS: This study aimed to quantitatively examine periarterial innervation in human epicardial coronary arteries. METHODS: Coronary arteries with adjacent epicardial adipose tissue were excised along the left main coronary artery (LMCA), left anterior descending artery (LAD), left circumflex artery (LCx), and right coronary artery (RCA) from 28 body donors and examined histologically. Immunofluorescence staining was performed to characterise sympathetic nerve fibres. RESULTS: A total of 42,573 nerve fibres surrounding 100 coronary arteries (LMCA: n=21, LAD: n=27, LCx: n=26, RCA: n=26) were analysed. The nerve fibre diameter decreased along the vessel course (median [interquartile range]): (proximal 46 µm [31-73], middle 38 µm [26-58], distal 31 µm [22-46]; p<0.001), with the largest nerve fibre diameter along the LMCA (50 µm [31-81]), followed by the LAD (42 µm [27-72]; p<0.001). The total nerve fibre density was highest along the RCA (123 nerves/cm² [82-194]). Circumferentially, nerve density was higher in the myocardial tissue area of the coronary arteries (132 nerves/cm² [76-225]) than in the epicardial tissue area (101 nerves/cm² [61-173]; p<0.001). The median lumen-nerve distance was smallest around the LMCA (2.2 mm [1.2-4.1]), followed by the LAD (2.5 mm [1.1-4.5]; p=0.005). CONCLUSIONS: Human coronary arteries are highly innervated with sympathetic nerve fibres, with significant variation in the distribution and density. Understanding these patterns informs pathophysiological understanding and, potentially, the development of catheter-based approaches for cardiac autonomic modulation.

In vivo biocompatibility of a new hydrophobic coated Al/Al2O3 nanowire surface on stents.

BACKGROUND: Intima proliferation and in-stent restenosis is a challenging situation in interventional treatment of small vessel obstruction. Al/Al2O3 nanowires have been shown to accelerate vascular endothelial cell proliferation and migration in vitro, while suppressing vascular smooth muscle cell growth. Moreover, surface modification of Al/Al2O3 nanowires with poly[bis(2,2,2-trifluoromethoxy)phosphazene (PTFEP) coating enables further advantages such as reduced platelet adhesion. Therefore, the study's goal was to compare the biocompatibility of novel Al/Al2O3 + PTFEP coated nanowire bare-metal stents to uncoated control stents in vivo using optical coherence tomography (OCT), quantitative angiography and histomorphometric assessment. METHODS: 15 Al/Al2O3 + PTFEP coated and 19 control stents were implanted in the cervical arteries of 9 Aachen minipigs. After 90 days, in-stent stenosis, thrombogenicity, and inflammatory response were assessed. Scanning electron microscopy was used to analyse the stent surface. RESULTS: OCT analysis revealed that neointimal proliferation in Al/Al2O3 + PTFEP coated stents was significantly reduced compared to control stents. The neointimal area was 1.16 ± 0.77 mm2 in Al/Al2O3 + PTFEP coated stents vs. 1.98 ± 1.04 mm2 in control stents (p = 0.004), and the neointimal thickness was 0.28 ± 0.20 vs. 0.47 ± 0.10 (p = 0.003). Quantitative angiography showed a tendency to less neointimal growth in coated stents. Histomorphometry showed no significant difference between the two groups and revealed an apparent inflammatory reaction surrounding the stent struts. CONCLUSIONS: At long-term follow-up, Al/Al2O3 + PTFEP coated stents placed in peripheral arteries demonstrated good tolerance with no treatment-associated vascular obstruction and reduced in-stent restenosis in OCT. These preliminary in vivo findings indicate that Al/Al2O3 + PTFEP coated nanowire stents may have translational potential to be used for the prevention of in-stent restenosis.

Paclitaxel-coated versus sirolimus-coated balloon angioplasty for coronary artery disease: A systematic review and meta-analysis.

BACKGROUND: Although use of sirolimus-based analogs has shown superiority over paclitaxel in drug-eluting stents, the relative efficacy of these two agents released from drug-coated balloons (DCB) is unclear. The present meta-analysis is aimed to compare outcomes after percutaneous coronary intervention (PCI) with paclitaxel-coated balloons (PCB) versus sirolimus-coated balloons (SCB) for either in-stent restenosis or native de novo lesions. METHODS: The study outcomes were 1) target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction, or target lesion revascularization, and 2) follow-up angiographic parameters including late lumen loss (LLL), diameter stenosis, and minimal lumen diameter (MLD). Pooled odds ratios (OR) and weighted mean differences (WMD) with 95% confidence intervals (CI) were calculated by using random-effects models. RESULTS: A search of PubMed, EMBASE, and Cochrane Library from their inception to January 2024 identified five randomized clinical trials and three observational studies with a total of 1861 patients (889 in PCB and 972 in SCB groups). During 9-12 months of follow-up, there was no significant difference in TLF (OR 1.01, 95% CI 0.75-1.35) between the two groups. On follow-up angiography at 6-9 months, MLD (WMD 0.10, 95% CI 0.02-0.17) was larger in PCB but there was no statistically significant difference in LLL (WMD -0.11, 95% CI -0.23-0.02) and diameter stenosis (WMD -3.33, 95% CI -8.11-1.45). CONCLUSIONS: Among patients undergoing DCB-only PCI, the risk of TLF was similar during 9-12 months of follow-up after PCB and SCB treatment. However, the MLD was larger favoring PCB over SCB on follow-up angiography.

Comparison of angiographic change in side-branch ostium after drug-coated balloon vs. drug-eluting stent vs. medication for the treatment of de novo coronary bifurcation lesions.

OBJECTIVES: Data on side-branch (SB) ostial effect after drug-coated balloon (DCB) treatment in the context of de novo coronary bifurcation lesions are limited. We aimed to investigate the angiographic outcomes of SB ostium after DCB treatment compared with drug-eluting stents (DESs) implantation in the main vessel (MV) or optimal medical therapy (OMT) for the treatment of de novo coronary bifurcation lesions. METHODS: Serial angiographic changes in the SB ostium were compared between DCB, DES, and medication alone for MV treatment. Δ value was calculated by subtracting the follow-up value from the pre-procedure value. RESULTS: A total of 132 bifurcation lesions were included for analysis (44 lesions in DCB group; 38 lesions in DES group; 50 lesions in OMT group). The minimal lumen diameter (MLD) of SB ostium showed an increase at follow-up in the DCB group, whereas a decrease was observed in both the DES and OMT groups (ΔMLD: -0.16 ± 0.45 mm for DCB group vs. 0.50 ± 0.52 mm for DES group vs. 0.08 ± 0.38 mm for OMT group, p < 0.001). The diameter stenosis (DS) of SB ostium showed a marked decrease at follow-up in the DCB group, in contrast to an increase observed in both the DES and OMT groups (ΔDS: 8.01 ± 18.96% for DCB group vs. -18.68 ± 18.60% for DES group vs. -2.05 ± 14.58% for OMT group, p < 0.001). CONCLUSIONS: In de novo coronary bifurcation lesions, DCB treatment on the MV demonstrated favorable angiographic outcomes in the SB ostium at 6-9 month follow-up compared to DES implantation or OMT.

Editorial: Is the axiom of balloon angioplasty, "the more you gain the more you lose", still true in the era of DCB with paclitaxel?

Balloon angioplasty achieves luminal enlargement by fracturing the atherosclerotic intima at its point of least resistance, thereby creating a dissection plane and space with dehiscence of the intima from the media. This barotraumatic dissection triggers an inflammatory and proliferative reaction, resulting in a restenosis process at medium-term. In the era of plain old balloon angioplasty, quantitative angiographic studies at follow-up demonstrated that - the greater the acute luminal gain was after balloon angioplasty, the greater the late luminal loss was at follow-up. The interventional cardiologists coined the following motto "the more you gain, the more you lose". However, in the current era of drug coated balloon (DCB), it appears that this vexing conundrum could have been abrogated. A recently published DCB study in small de novo vessel has demonstrated that there was a slightly negative correlation between the volume of dissection assessed by optical coherence tomography and the angiographic late luminal loss (now gain) after Paclitaxel coated balloon treatment. In other words, the barotraumatic dissection does not necessarily herald a restenosis process in the era of DCB. This article revisits the mechanism of balloon angioplasty and explores how DCB with Paclitaxel may change the paradigm of balloon angioplasty as default treatment in CAD percutaneous treatment.

Mechanical thrombectomy in intermediate- and high-risk acute pulmonary embolism: hemodynamic outcomes at three months.

BACKGROUND: Mechanical thrombectomy has been shown to reduce thrombus burden and pulmonary artery pressure (PAP) and to improve right ventricular (RV) function in patients with high-risk or intermediate-high-risk pulmonary embolism (PE). As hemodynamic data after mechanical thrombectomy for PE are scarce, we aimed to assess the hemodynamic effects of mechanical thrombectomy in acute PE with right heart overload. METHODS: In this prospective, open-label study, patients with acute symptomatic, computed tomography-documented PE with signs of right heart overload underwent mechanical thrombectomy using the FlowTriever System. Right heart catheterization was performed immediately before and after thrombectomy and after three months. Transthoracic echocardiography was performed before thrombectomy, discharge, and at three months. This analysis was done after 20 patients completed three months of follow-up. RESULTS: Twenty-nine patients (34% female) underwent mechanical thrombectomy, of which 20 completed three months follow-up with right heart catheterization. Most patients were at high (17%) or intermediate-high (76%) risk and had bilateral PE (79%). Before thrombectomy, systolic PAP (sPAP) was severely elevated (mean 51.3 ± 11.6 mmHg). Mean sPAP dropped by -15.0 mmHg (95% confidence interval [CI]: -18.9 to -11.0; p < 0.001) immediately after the procedure and continued to decrease from post-thrombectomy to three months (-6.4 mmHg, 95% CI: -10-0 to -2.9; p = 0.002). RV/left ventricular (LV) ratio immediately reduced within two days by -0.37 (95% CI: -0.47 to -0.27; p < 0.001). The proportion of patients with a tricuspid annular plane systolic excursion (TAPSE)/sPAP ratio < 0.31 mm/mmHg decreased from 28% at baseline to 0% before discharge and at three months (p = 0.007). There were no procedure-related major adverse events. CONCLUSIONS: Mechanical thrombectomy for acute PE was safe and immediately reduced PAP and improved right heart function. The reduction in PAP was maintained at three months follow-up.

Sex-specific inequalities in the use of drug-coated balloons for small coronary artery disease: a report from the BASKET-SMALL 2 trial.

BACKGROUND AND OBJECTIVES: Recent data have established non-inferiority of drug-coated balloons (DCB) compared to drug-eluting stents (DES) for treatment of small-vessel coronary artery disease. Since coronary vessels in women might have anatomical and pathophysiological particularities, the safety of the DCB strategy among women compared to men needs to be assessed in more detail. METHODS: In BASKET-SMALL 2, patients with de novo lesions in coronary vessels < 3 mm and an indication for percutaneous coronary intervention were randomly allocated (1:1) to DCB vs. DES after successful lesion preparation. The primary objective of the randomized trial was to establish non-inferiority of DCB vs. DES regarding major adverse cardiac events (MACE; i.e., cardiac death, non-fatal myocardial infarction, and target vessel revascularization) after 12 months. The aim of the current sub-analysis is to evaluate whether the DCB strategy is equally safe among women and men after 12 and 36 months. RESULTS: Among 758 randomized patients, 382 were assigned to DCB (23% women) and 376 to DES (30% women). In general, women were older, had more often diabetes mellitus and renal insufficiency, and presented more often with an acute coronary syndrome, whereas men were more often smokers, had multivessel disease and a previous history of acute myocardial infarction, and received a treatment with a statin. After 3 years, the primary clinical end point was not significantly different between groups (13% women vs. 16% men, HR 0.82; 95% CI 0.52-1.30; p = 0.40). There was no interaction between sex and coronary intervention strategy regarding MACE at 36 months (10% women vs. 16% men in DCB, 16% women vs. 15% men in DES; pinteraction = 0.31). CONCLUSION: In small native coronary artery disease, there was no statistically significant effect of sex on the difference between DCB and DES regarding MACE up to 36 months. CLINICAL TRIAL REGISTRATION: URL: http://www. CLINICALTRIALS: gov . Unique identifier: NCT01574534. CAD coronary artery disease, MACE major adverse cardiovascular events, HR Hazard ratio, DCB drug-coated balloon, DES drug-eluting stent.

Impact of Insulin-Treated Compared to Non-Insulin-Treated Diabetes Mellitus on Outcome of Percutaneous Coronary Intervention with Drug-Coated Balloons versus Drug-Eluting Stents in De Novo Coronary Artery Disease: The Randomized BASKET-SMALL 2 Trial.

BACKGROUND: We evaluated the outcome of PCI of de novo stenosis with drug-coated balloons (DCB) versus drug-eluting stents (DES) in patients with insulin-treated diabetes mellitus (ITDM) versus non-insulin-treated diabetes mellitus (NITDM). METHODS: Patients were randomized in the BASKET-SMALL 2 trial to DCB or DES and followed over 3 years for MACE (cardiac death, non-fatal myocardial infarction [MI], and target vessel revascularization [TVR]). Outcome in the diabetic subgroup (n = 252) was analyzed with respect to ITDM or NITDM. RESULTS: In NITDM patients (n = 157), rates of MACE (16.7% vs. 21.9%, hazard ratio [HR] 0.68, 95% confidence interval [CI] 0.29-1.58, p = 0.37), death, non-fatal MI, and TVR (8.4% vs. 14.5%, HR 0.30, 95% CI 0.09-1.03, p = 0.057) were similar between DCB and DES. In ITDM patients (n = 95), rates of MACE (DCB 23.4% vs. DES 22.7%, HR 1.12, 95% CI 0.46-2.74, p = 0.81), death, non-fatal MI, and TVR (10.1% vs. 15.7%, HR 0.64, 95% CI 0.18-2.27, p = 0.49) were similar between DCB and DES. TVR was significantly lower with DCB versus DES in all diabetic patients (HR 0.41, 95% CI 0.18-0.95, p = 0.038). CONCLUSIONS: DCB compared to DES for treatment of de novo coronary lesions in diabetic patients was associated with similar rates of MACE and numerically lower need for TVR both for ITDM and NITDM patients.

One single drug-coated balloon for all shapes/diameters? Neointimal proliferation inhibition in porcine peripheral arteries.

BACKGROUND: Long diseased vessel segments of peripheral arteries may display irregular shapes with different diameters. The aim of this study was to investigate inhibition of neointimal proliferation in porcine peripheral vessels with different diameters covered by one single hyper-compliant drug-coated balloon (HCDCB), compared to conventional drug-coated balloons (DCB), each selected according to the respective vessel diameter. METHODS AND RESULTS: Neointimal proliferation was stimulated in proximal and distal segments of the peripheral arteries by balloon overstretch and stent implantation. Inhibition of neointimal proliferation by one single HCDCB was compared to two vessel diameter-adjusted DCB per artery and to one single uncoated hyper-compliant balloon (HCB). Sixteen HCB, 16 HCDCB, and 32 DCB were used in 16 arteries each. Quantitative angiography (QA), optical coherence tomography (OCT) and histology showed a similar anti-restenotic effect for one HCDCB compared to two vessel diameter-adjusted DCB in narrow distal and wider proximal segments (QA diameter stenosis: 18.7±12.3% vs. 22.8±15.5%, p = 0.535; OCT area stenosis: 21.4±11.6% vs. 23.6±12.3%, p = 0.850; histomorphometry diameter stenosis: 27.5±7.1% vs. 26.9±8.0%, p = 0.952) and indicated significant inhibition of neointimal proliferation by HCDCB vs. uncoated HCB (QA diameter stenosis: 18.7±12.3% vs. 30.3±16.7%, p = 0.008; OCT area stenosis: 21.4±11.6% vs. 34.7±16.0%, p = 0.004; histomorphometry diameter stenosis: 27.5±7.1% vs. 32.5±8.5%, p = 0.038). CONCLUSIONS: HCDCB were found to be similar effective as DCB in inhibiting neointimal proliferation in vessel segments with different diameters. One single long HCDCB may allow for treatment of segments with variable diameters, and thus, replace the use of several vessel diameter-adjusted DCB.

Prediction of conduction disturbances in patients undergoing transcatheter aortic valve replacement.

AIM: Transcatheter aortic valve replacement (TAVR) can cause intraventricular conduction disturbances (ICA), particularly left bundle branch block (BBB) and high-degree atrioventricular block (HAVB). The aim of this study was to investigate clinical, anatomical, procedural, and electrophysiological parameters predicting ICA after TAVR. METHODS: Patients with severe aortic stenosis (n = 203) without pacing devices undergoing TAVR with a self-expanding (n = 103) or balloon-expanding (n = 100) valve were enrolled. Clinical and anatomical parameters, such as length of the membranous septum (MS) and implantation depth, were assessed. His-ventricular interval (HVi) before and after implantation was determined. 12-lead-electrocardiograms (ECG) before, during and after 3 and 30 days after TAVR were analyzed for detection of any ICA. RESULTS: Among 203 consecutive patients (aortic valve area 0.78 ± 0.18 cm2, age 80 ± 6 years, 54% male, left ventricular ejection fraction 52 ± 10%), TAVR led to a significant prolongation of infranodal conduction in all patients from 49 ± 10 ms to 59 ± 16 ms (p = 0.01). The HVi prolongation was independent of valve types, occurrence of HAVB or ICA. Fifteen patients (7%) developed HAVB requiring permanent pacemaker (PPM) implantation and 63 patients (31%) developed ICA within 30 days. Pre-existing BBB (OR 11.64; 95% CI 2.87-47.20; p = 0.001), new-onset left BBB (OR 15.72; 95% CI 3.05-81.03; p = 0.001), and diabetes mellitus (OR 3.88; 95% CI 1.30-15.99; p = 0.02) independently predicted HAVB requiring PPM. Neither pre-existing right BBB, a prolonged postHVi, increases in PR duration, any of the TAVR implantation procedural and anatomic nor echocardiographic characteristics were predictive for later HAVB. CONCLUSIONS: New-onset left BBB and diabetes mellitus independently predicted HAVB requiring PPM after TAVR and helped to identify patients at risk. Electrophysiologic study (EPS) of atrioventricular conduction was neither specific nor predictive of HAVB and can be skipped. TRIAL REGISTRATION NUMBER: NCT04128384 ( https://www. CLINICALTRIALS: gov ).

Coronary Drug-Coated Balloons for De Novo and In-Stent Restenosis Indications.

Drug-coated balloons are approved outside the United States, not only for the treatment of peripheral arteries but also for coronary arteries. This review describes the technological basics, the scenarios of clinical application, and the current available data from clinical trials for the different coronary indications.

Drug-Coated Balloons: Drugs Beyond Paclitaxel?

BACKGROUND: Although controversially discussed, paclitaxel is the only clinically proven drug that inhibits restenosis when released from drug-coated balloons (DCBs). Limus drugs are currently being explored as alternatives. The aim of the preclinical studies was to investigate drug candidates beyond paclitaxel considered for balloon coating. METHODS: Drugs were tested with respect to dissolution in organic solvents, coating on balloons, and drug transfer to the vessel wall. Inhibition of neointimal proliferation was tested in the porcine model of coronary in-stent stenosis. Intravascular drug treatment was achieved by DCBs at the time of stent implantation. RESULTS: Coating had to be adjusted for each drug. Doses on the balloons ranged from 1.0 to 8.6 µg/mm2 balloon surface. Satisfactory amounts of drug ranging from 5% to 29% of initial doses were transferred into the vessel wall. Angiographic parameters such as late lumen loss (LLL) at 4 weeks did not show reduction of in-stent neointimal proliferation by treatment with arsenic trioxide (0.87 ± 0.44 mm), betamethasone dipropionate (1.00 ± 0.54 mm), bortezomib (1.74 ± 0.46 mm), green tea extract (1.24 ± 0.51 mm), fantolon, an epothilone (0.86 ± 0.61 mm), methotrexate (1.09 ± 0.72 mm), and thalidomide (1.59 ± 0.55 mm) compared to treatment with uncoated balloons (1.07 ± 0.60 mm), while coatings with paclitaxel reliably reduced in-stent stenosis (LLL = 0.36 ± 0.25 mm). CONCLUSIONS: Despite the proven antiproliferative and/or anti-inflammatory effect of the drugs, none of the coatings significantly reduced LLL compared to uncoated balloons and thus, based on the results presented here, none of the tested coatings may be considered a substitute for the paclitaxel-based coatings currently in clinical use.

Inhibition of TRIF-Dependent Inflammation Decelerates Afterload-Induced Myocardial Remodeling.

Pressure-overload-induced cardiac hypertrophy represents one cause of the development of heart failure. The aim of this study is to characterize the influence of the TIR-domain-containing adapter-inducing interferon-ß (TRIF) during afterload-induced myocardial remodeling. After trans-aortic constriction (TAC), cardiac pressure overload leads to an early increase in MyD88- (Myeloid differentiation primary response gene 88) and TRIF-dependent cytokines. The maximum cytokine expression appeared within the first week and decreased to its control level within five weeks. While cardiomyocyte hypertrophy was comparable, the myocardial accumulation of the inflammatory cells was lower in TRIF-/-mice. At d7, TRIF deficiency reduced transcription factors and TRIF-dependent cytokines. Through the modulation of the TGF-ß-signaling pathway and anti-fibrotic microRNAs, TRIF was involved in the development of interstitial fibrosis. The absence of TRIF was associated with a decreased expression of proapoptotic proteins. In echocardiography and working heart analyses, TRIF deficiency slowed left-ventricular wall thickening, myocardial hypertrophy, and reduces the ejection fraction. In summary, TRIF is an important adapter protein for the release of inflammatory cytokines and the accumulation of inflammatory cells in the early stage of maladaptive cardiac remodeling. TRIF is involved in the development of cardiac fibrosis by modulating inflammatory and fibrotic signal transduction pathways.

Efficacy and safety of drug-coated balloons according to coronary vessel size. A report from the BASKET-SMALL 2 trial.

Introduction: In BASKET-SMALL 2, drug-coated balloons (DCB) were non-inferior to drug-eluting stents (DES) in de-novo stenosis of small coronary vessels (≤ 2.75 mm) regarding clinical endpoints up to 36 months. Aim: In the present subgroup analysis, we aimed to analyze the effect of the two treatment strategies in different vessel sizes. Material and methods: Patients were analyzed according to the size of the device used (small > 2.5 mm vs. very small ≤ 2.5 mm). The primary endpoint was major adverse cardiac events (MACE), while secondary endpoints were target vessel revascularization (TVR), non-fatal myocardial infarction, cardiac death, and all-cause mortality, all at 36 months. Interactions for the different groups were assessed with Cox regression analysis. Results: Overall, 758 patients were enrolled in this analysis, of which 437 (58%) had very small vessel disease. There were similar results in both treatment groups for the primary endpoint in both small and very small vessels (DCB vs DES, MACE at 3 years in small vessels HR = 1.31, 95% CI: 0.74-2.32, p = 0.355, and very small vessels HR = 0.82, 95% CI: 0.49-1.39, p = 0.468). Second generation paclitaxel-eluting stents showed significantly higher rates for MACE (p = 0.041), TVR (p = 0.004) and non-fatal myocardial infarction (p = 0.036) compared to DCB in very small coronary arteries at 3 years, while results were similar in small coronary arteries. Conclusions: Efficacy and safety of DCB are similar irrespective of vessel size. However, there is a beneficial effect of DCB over paclitaxel-eluting stents regarding TVR, non-fatal myocardial infarction and MACE that is most pronounced in very small coronary arteries.