Eosinophil-platelet interactions promote atherosclerosis and stabilize thrombosis with eosinophil extracellular traps.

Clinical observations implicate a role of eosinophils in cardiovascular diseases because markers of eosinophil activation are elevated in atherosclerosis and thrombosis. However, their contribution to atherosclerotic plaque formation and arterial thrombosis remains unclear. In these settings, we investigated how eosinophils are recruited and activated through an interplay with platelets. Here, we provide evidence for a central importance of eosinophil-platelet interactions in atherosclerosis and thrombosis. We show that eosinophils support atherosclerotic plaque formation involving enhanced von Willebrand factor exposure on endothelial cells and augmented platelet adhesion. During arterial thrombosis, eosinophils are quickly recruited in an integrin-dependent manner and engage in interactions with platelets leading to eosinophil activation as we show by intravital calcium imaging. These direct interactions induce the formation of eosinophil extracellular traps (EETs), which are present in human thrombi and constitute a substantial part of extracellular traps in murine thrombi. EETs are decorated with the granule protein major basic protein, which causes platelet activation by eosinophils. Consequently, targeting of EETs diminished thrombus formation in vivo, which identifies this approach as a novel antithrombotic concept. Finally, in our clinical analysis of coronary artery thrombi, we identified female patients with stent thrombosis as the population that might derive the greatest benefit from an eosinophil-inhibiting strategy. In summary, eosinophils contribute to atherosclerotic plaque formation and thrombosis through an interplay with platelets, resulting in mutual activation. Therefore, eosinophils are a promising new target in the prevention and therapy of atherosclerosis and thrombosis.

Real-world experience in initiation of treatment with the selective cardiomyosin inhibitor mavacamten in an outpatient clinic cohort during the 12-week titration period.

INTRODUCTION: Lately, mavacamten emerged as a new therapeutic option for symptomatic patients with obstructive hypertrophic cardiomyopathy (oHCM). Clinical trials revealed reduction of serum biomarkers, and left ventricular outflow tract (LVOT) obstruction, as well as an improvement in clinical symptoms and exercise capacity. Nevertheless, clinical experience and manageability of patients in a real-world setting is still lacking. MATERIAL AND METHODS: 22 patients with symptomatic oHCM (54.5% male, age 58.5 ± 16.2 years) and elevated LVOT gradients were started on mavacamten between March 2023 and June 2024. All patients were New York Heart Association (NYHA) class II or higher. Seven patients were excluded from primary analysis due to comedication with Angiotensin-converting-enzyme-inhibitors or Angiotensin-II receptor blockers. Cardiac imaging, laboratory work-up and clinical evaluation were assessed at three visits during the 12 weeks initiation phase; Dosing of mavacamten was adjusted according to manufacturer's recommendations. RESULTS: At 12 weeks, the majority of patients described a significant improvement of their quality of life. Work-up at 12 weeks revealed a significant reduction of serum biomarkers and LVOT gradients. In four patients, mavacamten needed to be temporarily paused due to clinical complaints or transient left ventricular ejection fraction deterioration below 50% with subsequent full recovery. CONCLUSION: We provide first insights into the usage of mavacamten in oHCM patients during the titration period in a real-world setting. Clinical findings are in line with previous clinical trials. In accordance with current recommendations, we highlight the need for standardized follow-up of patients on mavacamten treatment.

4-Year Follow-Up After Transcatheter Tricuspid Valve Replacement Using the EVOQUE System.

Transcatheter tricuspid valve replacement (TTVR) is an increasingly used treatment technique for patients with severe tricuspid regurgitation (TR). Currently, available data from international registries and randomized controlled trials provide outcome data until a maximum follow-up of 2 years after the procedure. This case report presents 4-year follow-up data for an 84-year-old woman who underwent TTVR for torrential TR in 2019. The patient experienced durable TR reduction, symptomatic improvement, right ventricular reverse remodeling, and substantial improvement in liver and kidney function.

Early Outcomes of Two Large Mitral Valve Transcatheter Edge-to-Edge Repair Devices-A Propensity Score Matched Multicenter Comparison.

Background/Objectives: Previous trials reported comparable results with PASCAL and earlier MitraClip generations. Limited comparative data exist for more contemporary MitraClip generations, particularly the large MitraClip XT(R/W). We aimed to evaluate acute and 30-day outcomes in patients undergoing mitral valve transcatheter edge-to-edge repair (M-TEER) with one of the large devices, either PASCAL P10 or MitraClip XT(R/W) (3rd/4th generation). Methods: A total of 309 PASCAL-treated patients were matched by propensity score to 253 MitraClip-treated patients, resulting in 200 adequately balanced pairs. Procedural, clinical, and echocardiographic outcomes were collected for up to 30 days, including subgroup analysis for mitral regurgitation (MR) etiologies. Results: PASCAL and MitraClip patients were comparable regarding age (80 vs. 79 years), sex (female: 45.5% vs. 50.5%), and MR etiology (degenerative MR: n = 94, functional MR [FMR]: n = 96, mixed MR: n = 10 in each group). Technical success rates were comparable (96.5% vs. 96.0%; p > 0.999). At discharge, the mean gradient was higher (3.3 mmHg vs. 3.0 mmHg; p = 0.038), and the residual mitral valve orifice area was smaller in MitraClip patients (3.0 cm2 vs. 2.3 cm2; p < 0.001). At discharge, the reduction to MR ≤ 2+ was comparable (92.4% vs. 87.8%; p = 0.132). However, reduction to MR ≤ 1+ was more frequently observed in PASCAL patients (67.7% vs. 56.6%; p = 0.029), driven by the FMR subgroup (74.0% vs. 60.0%; p = 0.046). No difference was observed in 30-day mortality (p = 0.204) or reduction in NYHA-FC to ≤II (p > 0.999). Conclusions: Both M-TEER devices exhibited high and comparable rates of technical success and MR reduction to ≤2+. PASCAL may be advantageous in achieving MR reduction to ≤1+ in patients with FMR.

Impact of Pulmonary Hypertension on Outcomes after Transcatheter Tricuspid Valve Edge-to-Edge Repair.

BACKGROUND: Data regarding the association of pulmonary hypertension (PH) and outcomes in patients undergoing transcatheter tricuspid valve edge-to-edge repair (T-TEER) are scarce. OBJECTIVES: To 1) investigate the impact of PH on outcomes after T-TEER and 2) to shed further light into the role of pre- and postcapillary PH in patients undergoing T-TEER for relevant tricuspid regurgitation (TR). METHODS: The study included patients from the EuroTR registry (NCT06307262) who underwent T-TEER for relevant TR from 2016 until 2023 with available invasive evaluation of sPAP using right heart catheterization. Study endpoints were procedural TR reduction, improvement in New York Heart Association (NYHA) function class and a combined endpoint of death or heart failure hospitalization (HFH) at two-years. RESULTS: Among a total of 1230 patients (mean age 78.6 ±7.0 years; 51.4% women) increasing systolic pulmonary artery pressure (sPAP) was independently associated with increasing rates of two-year death or HFH (hazard ratio 1.027, 95% confidence interval 1.003-1.052, p=0.030; median survival follow up 343 (114-645) days). No significant survival differences were observed for patients with pre- vs. postcapillary PH. Sensitivity analysis revealed a sPAP value of 46 mmHg as optimized threshold for prediction of death or HFH. Being observed in 526 patients (42.8%), elevated sPAP > 46 mmHg was associated with more severe heart failure symptoms at baseline and follow-up. Importantly, NYHA functional class and TR severity significantly improved irrespective of PH. CONCLUSION: PH is an important outcome predictor in patients undergoing T-TEER for relevant TR. In contrast to previous studies, no significant differences were observed for patients with pre- and postcapillary PH in terms of survival free from HFH.

Residual tricuspid regurgitation after tricuspid transcatheter edge-to-edge repair: Insights into the EuroTR registry.

AIMS: Data on the prognostic impact of residual tricuspid regurgitation (TR) after tricuspid transcatheter edge-to-edge repair (T-TEER) are scarce. The aim of this analysis was to evaluate 2-year survival and symptomatic outcomes of patients in relation to residual TR after T-TEER. METHODS AND RESULTS: Using the large European Registry of Transcatheter Repair for Tricuspid Regurgitation (EuroTR registry) we investigated the impact of residual TR on 2-year all-cause mortality and New York Heart Association (NYHA) functional class at follow-up. The study further identified predictors for residual TR ≥3+ using a logistic regression model. The study included a total of 1286 T-TEER patients (mean age 78.0 ± 8.9 years, 53.6% female). TR was successfully reduced to ≤1+ in 42.4%, 2+ in 40.0% and 3+ in 14.9% of patients at discharge, while 2.8% remained with TR ≥4+ after the procedure. Residual TR ≥3+ was an independent multivariable predictor of 2-year all-cause mortality (hazard ratio 2.06, 95% confidence interval 1.30-3.26, p = 0.002). The prevalence of residual TR ≥3+ was four times higher in patients with higher baseline TR (vena contracta >11.1 mm) and more severe tricuspid valve tenting (tenting area >1.92 cm2). Of note, no survival difference was observed in patients with residual TR ≤1+ versus 2+ (76.2% vs. 73.1%, p = 0.461). The rate of NYHA functional class ≥III at follow-up was significantly higher in patients with residual TR ≥3+ (52.4% vs. 40.5%, p < 0.001). Of note, the degree of TR reduction significantly correlated with the extent of symptomatic improvement (p = 0.012). CONCLUSIONS: T-TEER effectively reduced TR severity in the majority of patients. While residual TR ≥3+ was associated with worse outcomes, no differences were observed for residual TR 1+ versus 2+. Symptomatic improvement correlated with the degree of TR reduction.

Immobility-associated thromboprotection is conserved across mammalian species from bear to human.

Venous thromboembolism (VTE) comprising deep venous thrombosis and pulmonary embolism is a major cause of morbidity and mortality. Short-term immobility-related conditions are a major risk factor for the development of VTE. Paradoxically, long-term immobilized free-ranging hibernating brown bears and paralyzed spinal cord injury (SCI) patients are protected from VTE. We aimed to identify mechanisms of immobility-associated VTE protection in a cross-species approach. Mass spectrometry-based proteomics revealed an antithrombotic signature in platelets of hibernating brown bears with heat shock protein 47 (HSP47) as the most substantially reduced protein. HSP47 down-regulation or ablation attenuated immune cell activation and neutrophil extracellular trap formation, contributing to thromboprotection in bears, SCI patients, and mice. This cross-species conserved platelet signature may give rise to antithrombotic therapeutics and prognostic markers beyond immobility-associated VTE.

Impairment of Quality of Life in Patients with Implanted Subcutaneous Cardioverter Defibrillator (S-ICD) Compared to Implanted Transvenous Cardioverter Defibrillator Therapy.

Background: The subcutaneous cardioverter defibrillator (S-ICD) has been shown to be a viable alternative to transvenous ICDs (TV-ICD) in all patients at risk of sudden cardiac death (SCD) but without pacing indication. Aim: The aim of this study was to examine the impact of therapy with current S-ICD devices on quality of life (QoL) in comparison to patients with TV-ICD devices. Methods: In our single-centre study, 52 consecutive patients with S-ICD and 52 matched patients with TV-ICD were analysed. QoL has been assessed by a standardized questionnaire (EQ-5D-3L, modified). Additionally, clinical baseline and follow-up data were evaluated. Results: Two-thirds of the total study population reported restrictions in daily routine compared to their life before ICD implantation. A total of 27.7% of S-ICD patients stated to expect an improvement of QoL by deactivation or explantation of their defibrillator compared to only 6.4% of patients with TV-ICD (p=0.006), which was mainly caused by discomfort and pain from the S-ICD pocket (relevant discomfort and pain in 32.6% vs 11.5%; p<0.01). Limitations: Main limitation of the study is that quality of life was assessed for one single time point only and time since implantation differed significantly between S-ICD and TV-ICD. Furthermore our collective is younger, and, due to the high proportion of patients without cardiomyopathy, the mean EF is better than usual ICD collective. The absence of heart failure in about the half of our patients might have relevant impact on our QoL analysis. Conclusion: A relevant proportion of S-ICD patients expects an improvement of QoL by explantation of the device. Of note, this impression was not driven by the fear of receiving shocks but mainly by discomfort and pain caused by the pulse generator.

Prevalence of pathological arrhythmia in patients triaged to "cardiac arrhythmia" in the emergency department: a preliminary study.

BACKGROUND: Symptoms caused by cardiac arrhythmia are common problems that lead to presentation to the emergency department. However, the prevalence of pathological heart rhythm in patients triaged for cardiac arrhythmia in the emergency department remains up to now unknown. METHODS AND RESULTS: In this retrospective study, patients triaged for cardiac arrhythmia admitted to the interdisciplinary emergency department of the Ludwig-Maximilians University Hospital in Munich within 1 year were included. Subsequently, cardiac rhythm in the 12-lead electrocardiogram, clinical presentation, admission rate, and diagnosis at discharge was analyzed. A total of 558 out of 39,798 patients were triaged for cardiac arrhythmia. Of these 42.3% of patients showed a pathological heart rhythm on the initial electrocardiogram (66.9% atrial fibrillation, 16.5% atrial flutter, 16.5% others). About 80% presented in emergency severity index III (many resources are needed without critical vitals) conditions. Sixty-two percent of the pathological electrocardiogram group and 60% of the sinus rhythm group of patients were admitted to the hospital, and 34.7% with pathological electrocardiogram underwent invasive investigations (16.8% in the sinus rhythm group). In 43.4% of patients, the diagnosis of cardiac arrhythmia was already known from previous medical contacts. CONCLUSION: A total of 1.8% of patients who presented to our interdisciplinary emergency department were triaged for cardiac arrhythmia. With 49.5%, the hospital admission rate was quite high but the patients presented to the emergency department in our cohort were rarely in critical condition. As a high percentage of our cohort had a history of cardiac arrhythmia, better outpatient management is needed for these patients to reduce emergency department visits and save resources.

Presentation of Lung Carcinoid Tumor as Post-obstructive Pneumonia.

Carcinoid tumors consist of neuroendocrine cells that produce amines, polypeptides, and prostaglandins. The majority of carcinoid tumors are found in the gastrointestinal system while a minority originate as pulmonary neoplasms. Among lung cancers, carcinoid tumors are rare, compromising 1-2% of lung malignancies in the United States. Lung carcinoid tumors are characterized into typical and atypical classifications. Typical lung carcinoid tumors are often lower grade, slower growing, and more well-defined than atypical tumors. Atypical tumors are also more likely to metastasize than their typical counterparts. The patient presented in this article is a 35-year-old male with a history of recent hospital admission for pneumonia who presented with right chest pain. The patient was admitted eight days prior due to cough and acute hypoxemic respiratory failure secondary to post-obstructive pneumonia. During that admission, which totaled five days, he underwent a bronchoscopy and biopsy for a nodular right infrahilar opaque mass that appeared on computed tomography angiography of the chest. After the workup was negative, the patient was discharged. Three days later, he was re-admitted with continued chest pain. Biopsy results from the initial admission characterized the obstructing infrahilar mass as a carcinoid tumor with positive synaptophysin/ chromogranin stain and low proliferation (Mib1 < 2%). Following his discharge three days later, he was seen in follow-up by cardiothoracic surgery and underwent further imaging studies. Two months later, the patient underwent robotic right middle and lower bilobectomy. Pathologic analysis showed negative excised nodes and tumor margins. Often, patients presenting with post-obstructive pneumonia are thought to have an underlying etiology that is purely infectious. This can lead to a delay in the discovery of the primary cause of the obstruction, and the underlying malignancy. Fortunately for this case, a biopsy was performed during the initial hospitalization, which led to a modification of his treatment plan early on in his second hospital stay after the tumor was characterized.

Risk factors for intradialytic decline in cerebral perfusion and impaired cerebral autoregulation in adults on hemodialysis.

INTRODUCTION: Hemodialysis (HD) patients have significant burden of cerebral ischemic pathology noted on brain imaging. These ischemic type lesions maybe due to cerebral hypoperfusion that may be occurring during blood pressure (BP) fluctuations commonly noted during HD sessions. We evaluated changes in cerebral perfusion and measured an index of cerebral autoregulation (CA index) during HD to identify potential risk factors for intradialytic decline in cerebral perfusion and impaired cerebral autoregulation. METHODS: In this cross-sectional study, we included HD patients age 50 years or older receiving conventional in-center HD. We measured cerebral perfusion during HD, using cerebral oximetry, and calculated the correlation between cerebral perfusion and BP during HD as an index of CA. We measured the association between potential risk factors for intradialytic decline in cerebral perfusion and CA index. FINDINGS: We included 32 participants and 118 HD sessions in our analysis. The mean ± SD decline in cerebral oxygen saturation during HD was 6.5% ± 2.9% with a relative decline from baseline values of 9.2% ± 4.4%. Greater drop in systolic BP (SBP) during HD was associated with decline in cerebral oxygen saturation, p = 0.02. Impaired CA index was noted in 37.3% of HD sessions. Having diabetes and >20 mmHg drop in SBP during HD were associated with increased (worse) CA index with an increase of 0.24 95%CI [0.06, 0.41] for diabetes and increase of 0.43 95%CI [0.27, 0.56] for a >20 mmHg drop in SBP during HD. DISCUSSION: Cerebral perfusion can decline during HD and is associated with changes in systemic BP. This may be due to impaired cerebral autoregulation in HD patients. Risk factors for worse CA index include diabetes and >20 mmHg drop in SBP during HD. This study highlights the risk of intradialytic decline in cerebral perfusion and impaired cerebral autoregulation in HD patients.

Thrombus NET content is associated with clinical outcome in stroke and myocardial infarction.

OBJECTIVE: To investigate whether immune cell composition and content of neutrophil extracellular traps (NETs) in relation to clinical outcome are different between acute ischemic stroke (AIS) and acute myocardial infarction (AMI), we performed histologic analysis and correlated results with clinical and procedural parameters. METHODS: We retrieved thrombi from patients with AIS (n = 71) and AMI (n = 72) during endovascular arterial recanalization and analyzed their immune cell composition and NET content by immunohistology. We then associated thrombus composition with procedural parameters and outcome in AIS and with cardiac function in patients with AMI. Furthermore, we compared AIS thrombi with AMI thrombi and differentiated Trial of Org 10172 in Acute Stroke Treatment classifications to address potential differences in thrombus pathogenesis. RESULTS: Amounts of leukocytes (p = 0.133) and neutrophils (p = 0.56) were similar between AIS and AMI thrombi. Monocytes (p = 0.0052), eosinophils (p < 0.0001), B cells (p < 0.0001), and T cells (p < 0.0001) were more abundant in stroke compared with AMI thrombi. NETs were present in 100% of patients with AIS and 20.8% of patients with AMI. Their abundance in thrombi was associated with poor outcome scores in patients with AIS and with reduced ejection fraction in patients with AMI. CONCLUSION: In our detailed histologic analysis of arterial thrombi, thrombus composition and especially abundance of leukocyte subsets differed between patients with AIS and AMI. The presence and amount of NETs were associated with patients' outcome after AIS and AMI, supporting a critical impact of NETs on thrombus stability in both conditions.

Neoatherosclerosis in Patients With Coronary Stent Thrombosis: Findings From Optical Coherence Tomography Imaging (A Report of the PRESTIGE Consortium).

OBJECTIVES: The purpose of this study was to assess neoatherosclerosis in a registry of prospectively enrolled patients presenting with stent thrombosis using optical coherence tomography. BACKGROUND: In-stent neoatherosclerosis was recently identified as a novel disease manifestation of atherosclerosis after coronary stent implantation. METHODS: Angiography and intravascular optical coherence tomography were used to investigate etiologic factors of neoatherosclerosis in patients presenting with stent thrombosis >1 year after implantation (very late stent thrombosis [VLST]). Clinical data were collected according to a standardized protocol. Optical coherence tomographic acquisitions were analyzed in a core laboratory. Cox regression analysis was performed to identify factors associated with the formation of neoatherosclerosis and plaque rupture as a function of time. RESULTS: Optical coherence tomography was performed in 134 patients presenting with VLST. A total of 58 lesions in 58 patients with neoatherosclerosis were compared with 76 lesions in 76 patients without neoatherosclerosis. Baseline characteristics were similar between groups. In-stent plaque rupture was the most frequent cause (31%) in all patients presenting with VLST. In patients with neoatherosclerosis, in-stent plaque rupture was identified as the cause of VLST in 40 cases (69%), whereas uncovered stent struts (n = 22 [29%]) was the most frequent cause in patients without neoatherosclerosis. Macrophage infiltration was significantly more frequent in optical coherence tomographic frames with plaque rupture compared with those without (50.2% vs. 22.2%; p < 0.0001), whereas calcification was more often observed in frames without plaque rupture (17.2% vs. 4%; p < 0.0001). Implantation of a drug-eluting stent was significantly associated with the formation of neoatherosclerosis (p = 0.02), whereas previous myocardial infarction on index percutaneous coronary intervention was identified as a significant risk factor for plaque rupture in patients with neoatherosclerosis (p = 0.003). No significant difference was observed in thrombus composition between patients with or without neoatherosclerosis. CONCLUSIONS: Neoatherosclerosis was frequently observed in patients with VLST. Implantation of a drug-eluting stent was significantly associated with neoatherosclerosis formation. In-stent plaque rupture was the prevailing pathological mechanism and often occurred in patients with neoatherosclerosis and previous myocardial infarction at index percutaneous coronary intervention. Increased macrophage infiltration heralded plaque vulnerability in our study and might serve as an important indicator.

Histological comparison of arterial thrombi in mice and men and the influence of Cl-amidine on thrombus formation.

AIMS: Medical treatment of arterial thrombosis is mainly directed against platelets and coagulation factors, and can lead to bleeding complications. Novel antithrombotic therapies targeting immune cells and neutrophil extracellular traps (NETs) are currently being investigated in animals. We addressed whether immune cell composition of arterial thrombi induced in mouse models of thrombosis resemble those of human patients with acute myocardial infarction (AMI). METHODS AND RESULTS: In a prospective cohort study of patients suffering from AMI, 81 human arterial thrombi were harvested during percutaneous coronary intervention and subjected to detailed histological analysis. In mice, arterial thrombi were induced using two distinct experimental models, ferric chloride (FeCl3) and wire injury of the carotid artery. We found that murine arterial thrombi induced by FeCl3 were highly concordant with human coronary thrombi regarding their immune cell composition, with neutrophils being the most abundant cell type, as well as the presence of NETs and coagulation factors. Pharmacological treatment of mice with the protein arginine deiminase (PAD)-inhibitor Cl-amidine abrogated NET formation, reduced arterial thrombosis and limited injury in a model of myocardial infarction. CONCLUSIONS: Neutrophils are a hallmark of arterial thrombi in patients suffering from acute myocardial infarction and in mouse models of arterial thrombosis. Inhibition of PAD could represent an interesting strategy for the treatment of arterial thrombosis to reduce neutrophil-associated tissue damage and improve functional outcome.

Cathelicidins prime platelets to mediate arterial thrombosis and tissue inflammation.

Leukocyte-released antimicrobial peptides contribute to pathogen elimination and activation of the immune system. Their role in thrombosis is incompletely understood. Here we show that the cathelicidin LL-37 is abundant in thrombi from patients with acute myocardial infarction. Its mouse homologue, CRAMP, is present in mouse arterial thrombi following vascular injury, and derives mainly from circulating neutrophils. Absence of hematopoietic CRAMP in bone marrow chimeric mice reduces platelet recruitment and thrombus formation. Both LL-37 and CRAMP induce platelet activation in vitro by involving glycoprotein VI receptor with downstream signaling through protein tyrosine kinases Src/Syk and phospholipase C. In addition to acute thrombosis, LL-37/CRAMP-dependent platelet activation fosters platelet-neutrophil interactions in other inflammatory conditions by modulating the recruitment and extravasation of neutrophils into tissues. Absence of CRAMP abrogates acid-induced lung injury, a mouse pneumonia model that is dependent on platelet-neutrophil interactions. We suggest that LL-37/CRAMP represents an important mediator of platelet activation and thrombo-inflammation.