Patients with aortic stenosis have von Willebrand factor abnormalities and increased proliferation of endothelial colony forming cells

Differentiation of lung tissue-resident c-Kit+ cells into microvascular endothelial cells alleviates pulmonary vascular remodeling

Pulmonary vascular remodeling (PVR), encompassing microvascular loss and muscularization, contributes to multiple respiratory diseases. c-Kit+ cells exhibit differentiation potential into both endothelial cells (ECs) and smooth muscle cells. The potential role of lung c-Kit+ cell differentiation in PVR, however, remains unclear. Lung c-Kit+ cells increase in pulmonary hypertension patients and in the SU5416/hypoxia (SuHx)-induced PVR mouse model. Employing genetic lineage tracing and single-cell RNA sequencing (scRNA-seq), we elucidate that lung-resident c-Kit+ cells display an aerocyte and venular endothelial differentiation in the SuHx model. Ablation of tissue-resident c-Kit+ cells exacerbates PVR. We identify an Nr2f2-expressing c-Kit+ cell subgroup, which exhibitsvenous EC differentiation and increases during PVR. Notably, the elevation of Nr2f2 in c-Kit+ cells via AAV enhances differentiation and mitigates PVR. These findings underscore the protective role of lung tissue-resident c-Kit+ cells in PVR, achieved by differentiating into mature ECs. Targeting NR2F2 expression in c-Kit+ cells emerges as a promising strategy for reversing PVR.

Evaluating the Relationship Between Gastrointestinal Bleeding and Valvular Heart Disease: A Systematic Review of Clinical Studies

Background: Gastrointestinal angiodysplasia is a significant vascular anomaly characterized by dilated, tortuous blood vessels in the gastrointestinal tract. The current literature extensively documents the association between angiodysplasia and aortic stenosis, known as Heyde syndrome, characterized by the triad of aortic stenosis, GIB, and acquired von Willebrand syndrome. However, other valvular diseases, including mitral and tricuspid regurgitation, have also been implicated. This comprehensive systematic review aims to investigate the spectrum of valvular abnormalities, exploring the intricate mechanisms by which they contribute to gastrointestinal bleeding. Furthermore, it will evaluate the available surgical and nonsurgical treatment modalities, assessing their efficacy in mitigating the incidence of such bleeding. Methods: A comprehensive search of the Pubmed/MEDLINE database was conducted to identify relevant studies to retrieve relevant articles from August 2014 to August 2024. A combination of Medical Subject Heading (MeSH) terms and text words related to cardiac valvular diseases and GIB were used. MeSH terms included “gastrointestinal bleeding”, “heart valve diseases”, “hematochezia”, “heart valve prosthesis”, “bioprosthesis”, “native valve diseases”, and “mechanical valve”. Results: Forty-five papers met the inclusion criteria. Twenty-seven studies covered GIB in aortic valve disease, ten on mitral valve disease, two on tricuspid valve disease, and six on multiple valves. Conclusions: This systematic review demonstrates the association between angiodysplasia and aortic stenosis and highlights mitral regurgitation and tricuspid regurgitation as potential etiologies. Definitive management with valvuloplasty or valve replacement is vital to preventing the onset or recurrence of GIB in patients with valvular disease.

Gastrointestinal Angiodysplasia Resolution After Transcatheter Aortic Valve Implantation

Importance

Heyde syndrome is the cooccurrence of aortic stenosis and gastrointestinal bleeding secondary to vascular lesions, including angiodysplasias. Several studies have demonstrated cessation of gastrointestinal bleeding after transcatheter aortic valve implantation (TAVI), but the etiology and effects on vascular lesions are largely unknown.

Objective

To examine the associations of TAVI with gastrointestinal vascular lesions and identify factors associated with recovery among patients with iron deficiency anemia and severe aortic stenosis.

Design, Setting, and Participants

In this prospective, single-center cohort study, patients with iron deficiency anemia on the TAVI waiting list from September 2020 to February 2022 were assessed by capsule endoscopy. Those with vascular lesions were reassessed 6 months after TAVI. Endoscopic images were anonymized and evaluated by 2 independent researchers. Data were analyzed from September 2022 to August 2024.

Exposure

TAVI.

Main Outcomes and Measures

The primary outcome was the mean difference in the number of vascular lesions before vs after TAVI.

Results

A total of 24 patients (mean [SD] age, 77.4 [7.1] years; 18 [75.0%] male) underwent capsule endoscopy, and vascular lesions were present in 18 patients (75.0%). TAVI was performed in 15 of 18 patients with vascular lesions, of whom 11 agreed to a second capsule endoscopy. The mean (SD) number of vascular lesions across the gastrointestinal tract decreased from 6.4 (5.6) lesions before TAVI to 2.0 (2.1) lesions 6 months after TAVI (P = .04). The number of vascular lesions decreased in 9 of 11 patients (81.8%), including 6 patients (54.5%) who no longer had typical angiodysplasias. Resolution of angiodysplasias was less frequent in patients who had multiple valvular heart disease before TAVI (0 of 3 patients) vs those without multiple valvular heart disease (6 of 8 patients [75.0%]) and in patients with significant paravalvular leakage after TAVI (2 of 5 patients [40.0%]) vs those without significant leakage (4 of 6 patients [66.7%]).

Conclusions and Relevance

In this cohort study of 24 patients with iron deficiency anemia and severe aortic stenosis, angiodysplasias were present in 75.0% of patients. TAVI was associated with reduced size and number of angiodysplasias in these patients. These findings suggest that TAVI not only improves aortic stenosis but may also reduce gastrointestinal bleeding by resolving vascular lesions, offering a dual benefit for patients with Heyde syndrome.

Non-Invasive Ultrasound Therapy for Severe Aortic Stenosis: Early Effects on the Valve, Ventricle, and Cardiac Biomarkers (A Case Series)

Background: Transcatheter aortic valve replacement (TAVR) was developed for inoperable patients with severe aortic stenosis. However, despite TAVR advancements, some patients remain untreated due to complex comorbidities, necessitating less-invasive approaches. Non-invasive ultrasound therapy (NIUT), a new treatment modality, has the potential to address this treatment gap, delivering short ultrasound pulses that create cavitation bubble clouds, aimed at softening embedded calcification in stiffened valve tissue. Methods: In the prospective Valvosoft® Serbian first-in-human study, we assessed the safety and efficacy of NIUT and its impact on aortic valve hemodynamics, on the left ventricle, and on systemic inflammation in patients with severe symptomatic aortic stenosis not eligible for TAVR or surgery. Results: Ten patients were included. Significant improvements were observed in hemodynamic parameters from baseline to one month, including a 39% increase in the aortic valve area (from 0.5 cm2 to 0.7 cm2, p = 0.001) and a 23% decrease in the mean transvalvular gradient (from 54 mmHg to 38 mmHg, p = 0.01). Additionally, left ventricular global longitudinal strain significantly rose, while global wasted work significantly declined at one month. A dose-response relationship was observed between treatment parameters (peak acoustic power, intensity spatial-peak pulse-average, and mean acoustic energy) and hemodynamic outcomes. NIUT was safely applied, with no clinically relevant changes in high-sensitivity troponin T or C-reactive protein and with a numerical, but not statistically significant, reduction in brain natriuretic peptide (from 471 pg/mL at baseline to 251 pg/mL at one month). Conclusions: This first-in-human study demonstrates that NIUT is safe and confers statistically significant hemodynamic benefits both on the valve and ventricle.

Persistent Gastrointestinal Bleeding after Aortic Valve Replacement in Heyde's Syndrome

Heyde's syndrome (HS) represents an association between aortic stenosis and intestinal angiodysplasias, and it has been demonstrated that acquired von Willebrand disease plays a pivotal role in the pathophysiology of this syndrome. In patients with HS, von Willebrand factor deficiency represents an additional risk factor, further contributing to the risk of bleeding and anemia. We present the case of an 86-year-old patient diagnosed with HS and von Willebrand deficiency in 2018. Four years prior, the patient underwent surgical aortic valve replacement. Since then, she has been receiving chronic oral anticoagulation therapy with a vitamin K antagonist. The patient was admitted to the Internal Medicine Clinic due to semi-solid dark stools, diffuse abdominal pain, and asthenia. Upon examination, the patient presented with an altered general status and clinical signs suggestive of anemia. Laboratory findings revealed anemia with elevated INR and aPTT values. Colonic angiodysplasias were identified during a colonoscopy, although no sources of active bleeding were detected. On the 9th day of hospitalization, the patient experienced an episode of lower gastrointestinal bleeding. The pharmacological management was adjusted, and argon plasma coagulation was recommended. Following treatment of the angiodysplastic lesions, the patient's clinical evolution was favorable, with the correction of the anemia.

Prognostic Impact of High-Molecular-Weight von Willebrand Factor Multimer Ratio in Classical Low-Flow Low-Gradient Aortic Stenosis

INTRODUCTION

High-molecular-weight (HMW) von Willebrand factor (VWF) multimer deficiency occurs in classical low-flow, low-gradient (LF/LG) aortic stenosis (AS) due to shear force-induced proteolysis. The prognostic value of HMW VWF multimer deficiency is unknown. Therefore, we sought to evaluate the impact of HMW VWF multimer deficiency on clinical outcome.

METHODS

In this prospective research study, a total of 83 patients with classical LF/LG AS were included. All patients underwent dobutamine stress echocardiography to distinguish true-severe (TS) from pseudo-severe (PS) classical LF/LG AS. HMW VWF multimer ratio was calculated using densitometric Western blot band quantification. The primary endpoint was all-cause mortality.

RESULTS

Mean age was 79 ± 9 years, and TS classical LF/LG AS was diagnosed in 73% (n = 61) and PS classical LF/LG AS in 27% (n = 22) of all patients. Forty-six patients underwent aortic valve replacement (AVR) and 37 were treated conservatively. During a mean follow-up of 27 ± 17 months, 47 deaths occurred. Major bleeding complications after AVR (10/46; 22%) were more common in patients with HMW VWF multimer ratio <1 (8/17; 47%) in comparison to patients with a normal multimer pattern (2/29; 7%) at baseline (p = 0.003). In a multivariable Cox regression analysis, HMW VWF multimer deficiency was a predictor of all-cause mortality (HR: 3.02 [95% CI: 1.31-6.96], p = 0.009) in the entire cohort. This association was driven by higher mortality rates in the AVR group (multivariable-adjusted HR: 9.4; 95% CI 2.0-43.4, p = 0.004).

CONCLUSIONS

This is the first study to demonstrate the predictive value of HMW VWF multimer ratio for risk stratification in patients with classical LF/LG AS. HMW VWF multimer deficiency was associated with an increased risk of all-cause mortality and major bleeding complications after AVR.

Potentials of Endothelial Colony-Forming Cells: Applications in Hemostasis and Thrombosis Disorders, from Unveiling Disease Pathophysiology to Cell Therapy

Endothelial colony-forming cells (ECFCs) are endothelial progenitor cells circulating in a limited number in peripheral blood. They can give rise to mature endothelial cells (ECs) and, with intrinsically high proliferative potency, contribute to forming new blood vessels and restoring the damaged endothelium in vivo. ECFCs can be isolated from peripheral blood or umbilical cord and cultured to generate large amounts of autologous ECs in vitro. Upon differentiation in culture, ECFCs are excellent surrogates for mature ECs showing the same phenotypic, genotypic, and functional features. In the last two decades, the ECFCs from various vascular disease patients have been widely used to study the diseases' pathophysiology ex vivo and develop cell-based therapeutic approaches, including vascular regenerative therapy, tissue engineering, and gene therapy. In the current review, we will provide an updated overview of past studies, which have used ECFCs to elucidate the molecular mechanisms underlying the pathogenesis of hemostatic disorders in basic research. Additionally, we summarize preceding studies demonstrating the utility of ECFCs as cellular tools for diagnostic or therapeutic clinical applications in thrombosis and hemostasis.

Impact of transcatheter aortic valve implantation on circulating von Willebrand factor in patients with severe aortic stenosis

INTRODUCTION

Severe aortic stenosis (AS) can lead to degradation of high molecular weight (HMW) von Willebrand factor (VWF) which can result in haemostatic abnormalities. While studies have explored changes in VWF profiles before and after surgical aortic valve replacement (SAVR), the longer-term changes in VWF profiles pre- and post-transcatheter aortic valve implantation (TAVI) are less understood.

AIM

Our primary objective was to identify differences in VWF multimer profiles and VWF function pre-TAVI and 1-month post-TAVI. Our secondary objective was to correlate VWF markers with measures of AS severity.

METHODS

Adult patients with severe AS referred for TAVI at our institution were prospectively enrolled in this cohort study. Blood samples were collected for plasma analysis at three time points for all patients: 1 day pre-TAVI, 3 days post-TAVI, and 1-month post-TAVI. VWF antigen, activity, propeptide, collagen binding, multimers, and factor VIII coagulant activity were determined at each time point. Correlations between VWF parameters and severity of AS were assessed.

RESULTS

Twenty participants (15 males, five females) with severe AS were recruited for the study. There was a significant increase in HMW VWF between pre-procedure and 1-month post-TAVI (p < .05). There was a transient increase in VWF antigen levels and activity at 3-days post TAVI that decreased to pre-TAVI levels at 1-month. There were no statistically significant correlations between VWF markers and AS severity.

CONCLUSIONS

This is the first study to elucidate longer-term (>1 week) improvements in HMW VWF after a TAVI procedure in severe AS patients.

Effectiveness of aortic valve replacement in Heyde syndrome: a meta-analysis

AIMS

Heyde syndrome is the co-occurrence of aortic stenosis, acquired von Willebrand syndrome, and gastrointestinal bleeding. Aortic valve replacement has been demonstrated to resolve all three associated disorders. A systematic review and meta-analysis were performed to obtain best estimates of the effect of aortic valve replacement on acquired von Willebrand syndrome and gastrointestinal bleeding.

METHODS AND RESULTS

A literature search was performed to identify articles on Heyde syndrome and aortic valve replacement up to 25 October 2022. Primary outcomes were the proportion of patients with recovery of acquired von Willebrand syndrome within 24 h (T1), 24-72 h (T2), 3-21 days (T3), and 4 weeks to 2 years (T4) after aortic valve replacement and the proportion of patients with cessation of gastrointestinal bleeding. Pooled proportions and risk ratios were calculated using random-effects models. Thirty-three studies (32 observational studies and one randomized controlled trial) on acquired von Willebrand syndrome (n = 1054), and 11 observational studies on gastrointestinal bleeding (n = 300) were identified. One study reported on both associated disorders (n = 6). The pooled proportion of Heyde patients with acquired von Willebrand syndrome recovery was 86% (95% CI, 79%-91%) at T1, 90% (74%-96%) at T2, 92% (84%-96%) at T3, and 87% (67%-96%) at T4. The pooled proportion of Heyde patients with gastrointestinal bleeding cessation was 73% (62%-81%). Residual aortic valve disease was associated with lower recovery rates of acquired von Willebrand syndrome (RR 0.20; 0.05-0.72; P = 0.014) and gastrointestinal bleeding (RR 0.57; 0.40-0.81; P = 0.002).

CONCLUSION

Aortic valve replacement is associated with rapid recovery of the bleeding diathesis in Heyde syndrome and gastrointestinal bleeding cessation. Residual valve disease compromises clinical benefits.

Gastrointestinal bleeding during the transcatheter aortic valve replacement perioperative period: A Review

With the aging of the population, the incidence of senile degenerative valvular heart disease is expected to increase. Transcatheter aortic valve replacement (TAVR) has been used for patients at lower surgical risk with symptomatic severe aortic valve stenosis. Because of the improvements in TAVR technology and increasing experience of the operators, TAVR is regarded as a safe and feasible procedure. Bleeding events during the TAVR perioperative period, especially gastrointestinal (GI) bleeding, have been proven to be related to the long-term prognosis and mortality. Elderly patients with valvular heart disease are susceptible to GI bleeding because of their use of antithrombotic drugs, physical damage of coagulation factors, and GI angiodysplasia. Frequent GI bleeding and low levels of preoperative hemoglobin increase the risk of TAVR, especially for elderly patients. Because of these risks, which are easily overlooked, we should focus more attention on the perioperative management of TAVR. Reasonable screening tools, including blood examinations, risk evaluation scales, and endoscopy, are beneficial to the prevention of complications that can occur during the perioperative period. Additionally, medical therapy can safely help patients at high-risk for bleeding patients throughout the perioperative period. This study aimed to characterize the pathology of TAVR patients and discuss treatment strategies for GI bleeding during the perioperative period.

Baseline Anemia Is an Independent Predictor of Long-Term Mortality in Patients Undergoing Transcatheter Aortic Valve Implantation

This study aimed to investigate the relationship between baseline anemia and long-term mortality in a single-center retrospective study involving patients undergoing transcatheter aortic valve implantation (TAVI). The study population included 412 consecutive patients undergoing TAVI at a center for severe aortic valve stenosis between August 2011 and November 2018. The primary end point of the study was all-cause mortality. Baseline anemia was present in 50% of our study cohort. During the median follow-up of 29 months, all-cause mortality was observed in 40.3% of the whole study population and was more frequently observed in the anemic group compared with the nonanemic group (53.5% vs 27.1%, P < .001, respectively). Cox-regression analysis revealed that Society of Thoracic Surgeons Predicted Risk of Mortality score, previous stroke, pericardial tamponade, and neutrophil-lymphocyte ratio count are independent predictors of long-term mortality after TAVI. Additionally, the presence of anemia at baseline was an independent predictor of long-term mortality with a 2.3-fold difference in the anemic group compared with the nonanemic group (hazard ratio: 2.31, 95% CI: 1.59-3.37, P < .001). Baseline anemia was observed in half of our patient population undergoing TAVI, and baseline anemia was found to be an independent predictor of long-term mortality after TAVI.

Non-Coding RNAs as Blood-Based Biomarkers in Cardiovascular Disease

In 2020, cardiovascular diseases (CVDs) remain a leading cause of mortality and morbidity, contributing to the burden of the already overloaded health system. Late or incorrect diagnosis of patients with CVDs compromises treatment efficiency and patient's outcome. Diagnosis of CVDs could be facilitated by detection of blood-based biomarkers that reliably reflect the current condition of the heart. In the last decade, non-coding RNAs (ncRNAs) present on human biofluids including serum, plasma, and blood have been reported as potential biomarkers for CVDs. This paper reviews recent studies that focus on the use of ncRNAs as biomarkers of CVDs.

Illustrated State-of-the-Art Capsules of the ISTH 2020 Congress

The 2020 Congress of the International Society of Thrombosis and Haemostasis (ISTH) was held virtually July 12-15, 2019, due to the coronavirus disease 2019 pandemic. The congress convenes annually to discuss clinical and basic topics in hemostasis and thrombosis. Each year, the program includes State of Art (SOA) lectures given by prominent scientists. Presenters are asked to create Illustrated Capsules of their talks, which are concise illustrations with minimal explanatory text. Capsules cover major themes of the presentation, and these undergo formal peer review for inclusion in this article. Owing to the shift to a virtual congress this year, organizers reduced the program size. There were 39 SOA lectures virtually presented, and 29 capsules (9 from talks omitted from the virtual congress) were both submitted and successful in peer review, and are included in this article. Topics include the roles of the hemostatic system in inflammation, infection, immunity, and cancer, platelet function and signaling, platelet function disorders, megakaryocyte biology, hemophilia including gene therapy, phenotype tests in hemostasis, von Willebrand factor, anticoagulant factor V, computational driven discovery, endothelium, clinical and basic aspects of thrombotic microangiopathies, fibrinolysis and thrombolysis, antithrombotics in pediatrics, direct oral anticoagulant management, and thrombosis and hemostasis in pregnancy. Capsule authors invite virtual congress attendees to refer to these capsules during the live presentations and participate on Twitter in discussion. Research and Practice in Haemostasis and Thrombosis will release 2 tweets from @RPTHJournal during each presentation, using #IllustratedReview, #CoagCapsule and #ISTH2020. Readers are also welcome to utilize capsules for teaching and ongoing education.