Treatment of acquired von Willebrand syndrome in aortic stenosis with transcatheter aortic valve replacement

Incidence, predictors and clinical impact of upper gastrointestinal bleeding after transcatheter aortic valve replacement

BACKGROUND

Upper gastrointestinal (GI) bleeding following transcatheter aortic valve replacement (TAVR) is common in patients with aortic stenosis due to the combination of acquired type 2A von Willebrand disease and aspirin-based antiplatelet therapy. We aimed to investigate the incidence, predictors and clinical outcomes of late upper GI bleeding in patients undergoing TAVR.

METHODS

In a prospective TAVR registry, patients were stratified according to upper GI bleeding within 1 year of discharge.

RESULTS

Among the 3144 eligible patients, 54 (1.7%) experienced upper GI bleeding after discharge. Of these, 40 patients had major or life-threatening bleeding, while 14 had minor bleeding events. The presence of atrial fibrillation or atrial flutter (HRadjusted 2.98; 95% CI 1.65 to 5.38) and previous upper GI bleeding (HRadjusted 3.51; 95% CI 1.51 to 8.19) were independent predictors of upper GI bleeding, while the use of proton pump inhibitors at discharge (HRadjusted 0.49; 95% CI 0.27 to 0.89) and higher haemoglobin levels (1 g/dL increase) (HRadjusted 0.73; 95% CI 0.62 to 0.87) were protective. Patients who experienced major or life-threatening upper GI bleeding had a higher all-cause (73.7% vs 11.4%, HR 5.84; 95% CI 3.41 to 10.02) and cardiovascular mortality (31.6% vs 7.3%, HR 3.87; 95% CI 1.72 to 8.70) compared with those without upper GI bleeding.

CONCLUSIONS

Among patients who underwent TAVR, 1.7% of patients experienced upper GI bleeding within 1 year of discharge. Major or life-threatening upper GI bleeding was associated with an increased risk of all-cause and cardiovascular mortality.

TRIAL REGISTRATION NUMBER

NCT01368250.

Blood biomarkers in left-sided valvular heart disease

Valvular heart disease (VHD) is a common condition that poses several challenges from the standpoints of diagnosis and therapeutic management. While several studies have explored the role of blood biomarkers in assessing the severity and risk of progression of VHD, as well as in evaluating related cardiac damage and predicting the occurrence of adverse events, blood biomarkers are generally not considered criteria to trigger valve intervention in the latest European and American guidelines for VHD management. This review article provides an up-to-date overview of the utility of blood biomarkers to (i) assess the presence, severity, and progression of left-sided VHD; (ii) establish the presence and extent of cardiovascular damage; (iii) predict clinical outcomes before and after valve interventions; and (iv) identify patients at risk for early structural valve deterioration, valve thrombosis, and paravalvular leak.

Antithrombotic Therapy in High Bleeding Risk, Part I: Percutaneous Cardiac Interventions

Antithrombotic therapy after cardiac percutaneous interventions is key for the prevention of thrombotic events but is inevitably associated with increased bleeding, proportional to the number, duration, and potency of the antithrombotic agents used. Bleeding complications have important clinical implications, which in some cases may outweigh the expected benefit of reducing thrombotic events. Because the response to antithrombotic agents varies widely among patients, there has been a relentless effort toward the identification of patients at high bleeding risk (HBR), in whom modulation of antithrombotic therapy may be needed to optimize the balance between safety and efficacy. Among patients undergoing cardiac percutaneous interventions, recent advances in technology have allowed for strategies of de-escalation to reduce bleeding without compromising efficacy, and HBR patients are expected to benefit the most from such approaches. Guidelines do not extensively expand upon the topic of de-escalation strategies of antithrombotic therapy in HBR patients. In this review, we discuss the evidence and provide practical recommendations on optimal antithrombotic therapy in HBR patients undergoing various cardiac percutaneous interventions.

Investigation of von Willebrand factor multimer abnormalities before and after aortic valve replacement using the Hydragel-5 assay

BACKGROUND

Severe aortic stenosis (sAS) is associated with acquired von Willebrand syndrome (AVWS) by loss of high-molecular-weight multimers (HMWM) of von Willebrand factor (VWF), potentially resulting in perioperative bleeding. Analysis of VWF multimers remains challenging. Recently, the new, rapid Hydragel 5 assay has been developed, using electrophoretic protein separation for dividing VWF-multimers into low (LMWM), intermediate (IMWM), and HMWM, the hemostatically active part of VWF. Here, we evaluated its impact on predicting blood loss in presence of AVWS after surgical aortic valve replacement (SAVR).

METHODS

We prospectively examined 52 patients (age: 68 ± 7 years; 54 % male) admitted to SAVR. They were divided in two groups (A: normal VWF, n = 28; B: abnormal VWF, n = 24, defined as VWF-activity/antigen (VWF:Ac/Ag)-ratio < 0.7 and/or HMWM loss). Blood samples and echocardiographic data were collected before, seven days and three months after SAVR. Blood loss and transfusions were recorded.

RESULTS

Baseline characteristics and clinical data were similar in both groups. HMWM loss was present in 38.5 % of all patients. HMWM, the VWF:Ac/Ag- and HMWM/(IMWM+LMWM)-ratios were significantly decreased preoperatively in group B but normalized after SAVR. Bleeding, re-thoracotomy and transfusion rates were comparable. HMWM loss was inversely correlated with the peak aortic gradient (Pmax) and positively with the aortic valve area (AVA), while HMWM/(IMWM+LMWM)-ratio negatively correlated with the mean aortic gradient (Pmean).

CONCLUSION

HMWM and HMWM/(IMWM+LMWM)-ratio inversely correlate with severity of AS and normalize after SAVR. The Hydragel-5 assay's might be valuable for routine diagnostics to assess bleeding risk and postoperative normalization of AS and VWF abnormalities in SAVR patients.

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.

Defining high bleeding risk in patients undergoing transcatheter aortic valve implantation: a VARC-HBR consensus document

The identification and management of patients at high bleeding risk (HBR) undergoing transcatheter aortic valve implantation (TAVI) are of major importance, but the lack of standardised definitions is challenging for trial design, data interpretation, and clinical decision-making. The Valve Academic Research Consortium for High Bleeding Risk (VARC-HBR) is a collaboration among leading research organisations, regulatory authorities, and physician-scientists from Europe, the USA, and Asia, with a major focus on TAVI-related bleeding. VARC-HBR is an initiative of the CERC (Cardiovascular European Research Center), aiming to develop a consensus definition of TAVI patients at HBR, based on a systematic review of the available evidence, to provide consistency for future clinical trials, clinical decision-making, and regulatory review. This document represents the first pragmatic approach to a consistent definition of HBR evaluating the safety and effectiveness of procedures, devices and drug regimens for patients undergoing TAVI..

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.

Transcatheter aortic valve implantation for patients with heyde syndrome: A literature review of case reports

Objective

A systematic review of international case reports of patients with Heyde syndrome (HS) treated by transcatheter aortic valve implantation (TAVI) was conducted to explore the clinical characteristics of this group of patients and sirgical success. Methods: Electronic databases, including PubMed, Embase and CNKI, were searched with combinations of the search terms, Heyde syndrome, gastrointestinal bleeding, aortic stenosis, angiodysplasia and transcatheter aortic valve replacement. All case reports were screened according to inclusion criteria, and HS patient data was summarized.

Results

A total of 31 case reports concerned patients with a history of aortic stenosis and repeated gastrointestinal bleeding. Ultrasonic cardiograms (UCG) were recorded for 27 cases, including those with critical aortic stenosis (n = 26). Gastrointestinal sequelae were reported in 22 cases with duodenal and jejunal being the most common (n = 9). High-molecular-weight multimers of von Willebrand Factor (vWF-HMWM) were measured in 17 cases with the majority being lower (n = 15) and the minority normal (n = 2). All patients experienced recurrent bleeding after medication and endoscopic therapy and symptoms improved after TAVI (31/31). vWF was at normal levels in 11/12 cases post-TAVI. Twenty-five patients were followed up and 22 had no recurrence of symptoms giving an efficacy rate of 88% for TAVI in HS patients.

Conclusions

HS is characterized by angiodysplasia, aortic stenosis and von Willebrand disease with frequent recurrence of bleeding after drug and endoscopic treatment. TAVI is an effective therapy with an 88% resolution rate.

Incidence, source, and prognostic impact of major bleeding across the spectrum of aortic stenosis

BACKGROUND

Severe aortic stenosis (AS) has been associated with bleeding. However, there is a lack of prospective assessment of bleeding events and their clinical significance in a large population of outpatients with variable degree of AS severity.

OBJECTIVES

To assess the incidence, source, determinants, and prognostic impact of major bleeding in patients with variable degree of AS severity.

METHODS

Between May 2016 and December 2017, consecutive outpatients were included. Major bleeding was defined as type ≥3 bleed using the Bleeding Academic Research Consortium definition. Cumulative incidence was calculated with death as the competing event. Data was censored at time of aortic valve replacement.

RESULTS

Among 2,830 patients, 46 major bleeding events occurred (0.7%/year) during a median follow-up of 2.1 years (interquartile range: 1.4-2.7). Most frequent sites of bleeding were gastrointestinal (50%) and intracranial (30.4%). Major bleeding was significantly associated with all-cause mortality (hazard ratio: 5.93 (95% confidence interval 3.64-9.65); P < .001). AS severity was associated with major bleedings (P = .041). By multivariable analysis, severe AS was an independent determinant of major bleeding (hazard ratio vs mild AS: 3.59 [95% confidence interval 1.56-8.29]; P = .003). The increased risk of bleeding associated with severe AS was significantly exacerbated in patients using oral anticoagulation.

CONCLUSION

In AS patients, major bleeding is rare but a strong independent predictor of death. AS severity is a determinant of bleeding events. Severe AS and oral anticoagulation should be identified as an association at very high risk of major bleeding.

Bleeding Events After Transcatheter Aortic Valve Replacement: JACC State-of-the-Art Review

Transcatheter aortic valve replacement (TAVR) has gained over time a major reduction in procedural complications. Despite this, clinically relevant bleeding still occurs in a non-negligible proportion of patients and adversely affects prognosis. Patients with severe aortic stenosis are at heightened risk for spontaneous bleeding due to advanced age and a high comorbidity burden. Also, procedural factors and antithrombotic management contribute to define individual bleeding susceptibility. Bleeding prevention represents an emerging area for improving patient care. Because of the tight hemorrhagic/ischemic balance, a tailored approach based on individual bleeding-risk profile, such as a less invasive antithrombotic regimen or appropriate diagnostic preprocedural evaluation, should be pursued to avoid bleeding events. This review aims to provide an in-depth overview of bleeding events in the TAVR field, including definitions, timing and the extent of risk, and clinical impact, as well as updates on antithrombotic management and its potential influence on bleeding complications.

Severity of and Recovery From Anemia After Transcatheter Aortic Valve Replacement: An Analysis of the PARTNER Trials and Registries

Background

Anemia is associated with increased mortality in patients undergoing transcatheter aortic valve replacement (TAVR); however, data on the effect of the severity of and recovery from anemia on clinical outcomes are limited. This study examined the impact of the severity of and recovery from anemia after TAVR.

Methods

Patients with symptomatic, severe aortic stenosis across all surgical risk groups from the Placement of Aortic Transcatheter Valves (PARTNER) I, II, and III trials and registries who underwent TAVR were analyzed. Baseline anemia was defined as mild (hemoglobin [Hb] level ≥11.0 g/dL and <13.0 g/dL for men and ≥11.0 g/dL and <12.0 g/dL for women) and moderate-to-severe anemia (Hb level <11.0 g/dL). Recovery from anemia was defined as an increase of ≥1 g/dL in the Hb level. Patients with missing Hb information and major bleeding within 30 days were excluded. The association of the severity of and recovery from anemia with clinical outcomes was analyzed using multivariable Cox proportional hazards regression models. The primary outcome was 1-year all-cause mortality.

Results

The Kaplan-Meier estimate for 1-year all-cause mortality was 5.4%, 8.2%, and 14.5% in patients with no, mild, and moderate-to-severe anemia, respectively (P < .001). Recovery from anemia at 30 days occurred in 8.4% (229/2730) of all patients. Compared with those without baseline or 30-day anemia, patients with recovery from anemia had similar 1-year mortality (hazard ratio, 1.02; CI, 0.50-2.08; P = .96), whereas those without recovery from anemia had higher 1-year mortality (hazard ratio, 1.82; CI, 1.17-2.85; P = .009).

Conclusions

In patients undergoing TAVR, moderate-to-severe anemia is independently associated with increased 1-year mortality, and recovery from anemia after TAVR is associated with favorable outcomes. Further efforts are needed to determine whether preprocedural correction of anemia improves post-TAVR outcomes.

Acquired von Willebrand Syndrome Secondary to Normally Functioning Mechanical Aortic Valve and High-Output Cardiac State

Acquired von Willebrand syndrome (AVWS) is caused by an acquired deficiency of von Willebrand factor (VWF), a multimeric protein required for primary hemostasis. For patients with heart valve diseases, high gradient across the malfunctioning valves could cause elevated shear stress and damage the most effective large VWF, eventually resulting in AVWS. However, AVWS has not been reported in association with normally functioning mechanical valves. Herein, we reported a 74-year-old female who suffered from recurrent gastrointestinal bleeding with a history of mechanical aortic and mitral valve replacement. This patient's function/antigen ratio of VWF was decreased and gel electrophoresis revealed the loss of large VWF, which confirmed the diagnosis of AVWS. Echocardiogram showed that the function of the prostheses was normal. However, the gradient across aortic valve was increased due to a high cardiac state which is secondary to chronic anemia, resulting in the disruption of large VWF multimers and exacerbation of gastrointestinal (GI) bleeding. After managing the patient's anemia with transfusion, the gradient across the aortic valve had improved, with the resolution of GI bleeding. This is the first case report of AVWS that is associated with a normally functioning mechanical valve. AVWS should be considered one of the differential diagnoses if patients present with unexplained GI bleeding on the background of having prosthetic heart valves. The management of the underlying condition is essential.

The impact of bicuspid aortic valve morphology on von Willebrand factor function in patients with severe aortic stenosis and its change after TAVI

BACKGROUND

Aortic stenosis (AS) can cause acquired von Willebrand syndrome (AVWS) and valve replacement has been shown to lead to von Willebrand factor (vWF) recovery. The aim of the current study was to investigate the prevalence of AVWS in different severe AS phenotypes and its course after transcatheter aortic valve implantation (TAVI).

METHODS

143 patients with severe AS undergoing TAVI were included in the study. vWF function was assessed at baseline, 6 and 24 h after TAVI. AVWS was defined as a reduced vWF:Ac/Ag ratio ≤ 0.7. Phenotypes were classified by tricuspid (TAV) and bicuspid (BAV) valve morphology, mean transvalvular gradient (P_mean), stroke volume index (SVI), ejection fraction (EF) and indexed effective orifice area (iEOA).

RESULTS

AVWS was present in 36 (25.2%) patients before TAVI. vWF:Ac/Ag ratio was significantly lower in high gradient compared to low-gradient severe AS [0.78 (IQR 0.67-0.86) vs. 0.83 (IQR 0.74-0.93), p < 0.05] and in patients with BAV compared to TAV [0.70 (IQR 0.63-0.78) vs. 0.81 (IQR 0.71-0.89), p < 0.05]. Normalization of vWF:Ac/Ag ratio was achieved in 61% patients 24 h after TAVI. As in the overall study cohort, vWF:Ac/Ag ratio increased significantly in all severe AS subgroups 6 h after TAVI (each p < 0.05). Regarding binary logistic regression analysis, BAV was the only significant predictor for AVWS.

CONCLUSIONS

BAV morphology is a strong predictor for AVWS in severe AS. TAVI restores vWF function in most patients with severe AS independently of AS phenotype and valve morphology.

Outcomes, Trends, and Predictors of Gastrointestinal Bleeding in Patients Undergoing Transcatheter Aortic Valve Implantation (from the National Inpatient Sample)

Major bleeding has been identified as one of the most common complications after transcatheter aortic valve implantation (TAVI) with some suffering gastrointestinal bleeding (GIB). This study aimed at assessing the incidence and predictors of GIB after TAVI in the United States. We performed a retrospective analysis of data from the National Inpatient Sample database from 2011 to 2018. A total of 216,023 hospitalizations for TAVI were included. Of the included patients, 2,188 (1%) patients had GIB, whereas 213,835 (99%) patients did not have GIB. The presence of arteriovenous malformation was associated with the highest odds of having a gastrointestinal bleed (odds ratio (OR) 24.8, 95% confidence interval (CI) 17.13 to 35.92). Peptic ulcer disease was associated with an eightfold increased risk of bleeding (OR 8.74, 95% CI, 6.69 to 11.43) followed closely by colorectal cancer (OR 7.89, 95% CI, 5.33 to 11.70). Other comorbidities that were associated with higher propensity-matched rates of GIB were chronic kidney disease (OR 1.27,95% CI, 1.14 to 1.41), congestive heart failure (OR 1.18, 95% CI,1.06 to 1.32), liver disease (OR1.83, 95% CI,1.53 to 2.19), end-stage renal disease (OR 2.08,95% CI, 1.75 to 2.47), atrial fibrillation (OR1.63,95% CI,  1.49 to 1.78), and lung cancer (OR 2.80, 95% CI,1.77 to 4.41). Patients with GIB had higher propensity-matched rates of mortality than those without GIB, (12.1% vs 3.2%, p <0.01). Patients with GIB had a higher median cost of stay ($68,779 vs $46,995, p <0.01) and a longer length of hospital stay (11 vs 3 days, p <0.01). In conclusion, health care use and mortality are higher in hospitalizations of TAVI with a GIB. Baseline comorbidities like peptic ulcer disease, chronic kidney disease, liver disease, atrial fibrillation and, colorectal cancer are significant predictors of this adverse event.

Platelets: Implications in Aortic Valve Stenosis and Bioprosthetic Valve Dysfunction From Pathophysiology to Clinical Care

Aortic stenosis (AS) is the most common heart valve disease requiring surgery in developed countries, with a rising global burden associated with aging populations. The predominant cause of AS is believed to be driven by calcific degeneration of the aortic valve and a growing body of evidence suggests that platelets play a major role in this disease pathophysiology. Furthermore, platelets are a player in bioprosthetic valve dysfunction caused by their role in leaflet thrombosis and thickening. This review presents the molecular function of platelets in the context of recent and rapidly evolving understanding the role of platelets in AS, both of the native aortic valve and bioprosthetic valves, where there remain concerns about the effects of subclinical leaflet thrombosis on long-term prosthesis durability. This review also presents the role of antiplatelet and anticoagulation therapies on modulating the impact of platelets on native and bioprosthetic aortic valves, highlighting the need for further studies to determine whether these therapies are protective and may increase the life span of surgical and transcatheter aortic valve implants. By linking molecular mechanisms through which platelets drive disease of native and bioprosthetic aortic valves with studies evaluating the clinical impact of antiplatelet and antithrombotic therapies, we aim to bridge the gaps between our basic science understanding of platelet biology and their role in patients with AS and ensuing preventive and therapeutic implications.

Aortic stenosis and Heyde’s syndrome: A comprehensive review

Heyde’s syndrome is an under reported systemic disease of gastrointestinal and cardiac manifestation in older adults. It is characterized by a triad of aortic stenosis, angiodysplasia with bleeding and acquired von Willebrand syndrome. It is characterized by proteolysis of high molecular weight multimers of von Willebrand Factor and loss of platelet mediated homeostasis. Heyde’s syndrome is a treatable condition in most cases, especially in the current era of evolution in interventional cardiology and gastroenterology. There are currently no established guidelines in the management of this condition due to paucity of high quality studies, which warrant future trials. High index of suspicion and increasing the awareness of the syndrome among the general practitioners and sub-specialists will improve the diagnostic potential of Heyde’s syndrome. Future studies may change the management aspect of Heyde's syndrome and pave a path for drawing specific guidelines and algorithms. The aim of our review article is to summarize the basic pathophysiology, diagnostics and management of Heyde’s syndrome with a special attention to Transcatheter aortic valve replacement.

Heyde syndrome: prevalence and outcomes in patients undergoing transcatheter aortic valve implantation

Background

Heyde syndrome (HS) is known as the association of severe aortic stenosis (AS) and recurrent gastrointestinal bleeding (GIB) from angiodysplasia. Data on the prevalence of HS and results after TAVI remain scarce.

Methods

2548 consecutive patients who underwent TAVI for the treatment of AS from 2008 to 2017 were evaluated for a history of GIB and the presence of HS. The diagnosis of HS was defined as a clinical triad of severe AS, a history of recurrent GIB, and an endoscopic diagnosis of angiodysplasia. These patients (Heyde) were followed to investigate clinical outcomes, bleeding complications and the recurrence of GIB and were compared to patients with GIB unrelated to HS (Non-Heyde).

Results

A history of GIB prior to TAVI was detected in 190 patients (7.5%). Among them, 47 patients were diagnosed with HS (1.8%). Heyde patients required blood transfusions more frequently compared to Non-Heyde patients during index hospitalization (50.0% vs. 31.9%, p = 0.03). Recurrent GIB was detected in 39.8% of Heyde compared to 21.2% of Non-Heyde patients one year after TAVI (p = 0.03). In patients diagnosed with HS and recurrent GIB after TAVI, the rate of residual ≥ mild paravalvular leakage (PVL) was higher compared to those without recurrent bleeding (73.3% vs. 38.1%, p = 0.05).

Conclusion

A relevant number of patients undergoing TAVI were diagnosed with HS. Recurrent GIB was detected in a significant number of Heyde patients during follow-up. A possible association with residual PVL requires further investigation to improve treatment options and outcomes in patients with HS.

Graphic abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00392-021-01905-z.

New Developments in Diagnosis and Management of Acquired Hemophilia and Acquired von Willebrand Syndrome

Acquired hemophilia A and acquired von Willebrand syndrome are rare, but life-threatening bleeding disorders that require prompt diagnosis and treatment by hematologists. Acquired hemophilia A is defined as an acquired severe bleeding tendency caused by autoantibody formation against coagulation factor VIII. Acquired von Willebrand syndrome is characterized by a new onset bleeding tendency caused by a reduced concentration and/or function of von Willebrand factor. These disorders are associated with a variety of underlying disorders, including various hematological malignancies, for example, plasma cell disorders, lymphoproliferative disorders, monoclonal gammopathy of undetermined significance, and myeloproliferative neoplasms. It is of utmost important to recognize these acquired bleeding disorders in these patients who are at risk for severe bleeding, and to perform additional diagnostic hemostasis laboratory evaluation. This will enable immediate diagnosis of the acquired bleeding disorder and management of both the bleeding episodes and the causative underlying disorder. In recent years, several new etiological factors for acquired hemophilia A, such as treatment with immune checkpoint inhibitors or DPP-4 inhibitors and SARS-CoV2 infection, and for acquired von Willebrand syndrome, for example, left ventricular assist devices, have been identified and also new treatment options have become available. In this concise review, the most recent data on etiology, diagnosis, and treatment of acquired bleeding disorders are presented and discussed.

Acquired von Willebrand syndrome in ECMO patients: A 3-year cohort study

BACKGROUND

Bleeding is a common but possibly underreported side effect of Extracorporeal Membrane Oxygenation (ECMO). Impairment of primary hemostasis by acquired von Willebrand syndrome (aVWS) and platelet dysfunction as well as activation and consumption of plasmatic coagulation factors contribute to hemorrhage. The aim of the present cohort study of consecutively enrolled patients admitted to our ECMO center was to collect demographic, medical and laboratory data possibly associated with i) development of clinically relevant bleeding and/or ii) death during a 12-months follow-up.

RESULTS

Within a 3-year period 338 white patients aged 18-89 years (median: 60; male 64.5%) were enrolled. 78 of 338 patients (23%) presented with clinical relevant bleeding symptoms. The overall death rate was 74.6% within a median time of 9 days (1-229) post intervention. Logistic-regression analysis adjusted for age and gender revealed that i) the presence of blood group O versus non-O (Odds ratio (OR)/95%CI: 1.9/1.007-3.41), ECMO duration per day (1.1/1.06-1.14), veno-venous versus veno-arterial ECMO cannulation (2.33/1.2-4.5) and the overall need for blood product administered per unit (1.02/1.016-1.028) was independenly associated with bleeding in patients suffering from aVWS. ii) Older age (increase per year) at ECMO start (1.015/1.012-1.029) and an increasing amount of blood product units were significantly related with death (1.007/1.001-1.013). Patients with veno-venous versus veno-arterial cannulation survived longer (0.48/0.24-0.94).

CONCLUSION

In the present cohort study we found a clinical relevant bleeding rate of 23% in subjects with aVWS associated with blood group O, a longer ECMO duration and veno-venous cannulation.

Heyde Syndrome-Pathophysiology and Perioperative Implications

Gastrointestinal (GI) bleeding in patients with calcific aortic valve stenosis (AVS), termed Heyde syndrome, was first described by Edward C. Heyde. The strong association between valvular replacement and the eradication of clinically significant GI bleeding confirmed an underlying pathophysiologic relationship. The rheologic stress created by AVS increases proteolysis of von Willebrand factor (VWF), resulting in loss of predominantly high-molecular-weight VWF (Hmw VWF). Angiodysplastic vessels present in patients with AVS, coupled with the lack of functioning Hmw VWF, increase the risk for GI bleeds. Aortic valve replacement, both surgical and transcatheter-based, is often a definitive treatment for GI bleeding, leading to recovery of Hmw VWF multimers. Perioperative management of patients involves monitoring their coagulation profiles with relevant laboratory tests and instituting appropriate management. Management can be directed in the following two ways: by improving internal release of VWF or by administration of external therapeutics containing VWF. It is important for perioperative physicians to obtain an understanding of the pathophysiology of this disease process and closely monitor the bleeding pattern so that targeted therapies can be initiated.

High-molecular-weight von Willebrand Factor multimer ratio differentiates true-severe from pseudo-severe classical low-flow, low-gradient aortic stenosis

AIMS

Upon high wall shear stress, high-molecular-weight (HMW) von Willebrand Factor (VWF) multimers are degraded, thus, HMW VWF multimer deficiency mirrors haemodynamics at the site of aortic stenosis (AS). The aim of the present study was to analyse the role of HMW VWF multimer ratio for subcategorization of classical low-flow, low-gradient (LF/LG) AS.

METHODS AND RESULTS

Eighty-three patients with classical LF/LG AS were prospectively recruited and HMW VWF multimer pattern was analysed using a densitometric quantification of western blot bands. Patients were subclassified into true-severe (TS) and pseudo-severe (PS) classical LF/LG AS based on dobutamine stress echocardiography (DSE). Positive and negative predictive values (PPV/NPV) of HMW VWF multimer ratio for diagnosis of the TS subtype were calculated. HMW VWF multimer ratio in TS classical LF/LG AS was significantly decreased compared to PS classical LF/LG AS (0.86 ± 0.27 vs. 1.06 ± 0.09, P < 0.001). HMW VWF multimer deficiency occurred exclusively in the TS subtype with an optimal PPV of 1.000 and NPV of 0.379. HMW VWF multimer ratio showed a strong correlation with mean transvalvular pressure gradients during DSE (r = -0.616; P < 0.001). HMW VWF multimer ratio measured at baseline was higher compared to levels measured after DSE (0.87 ± 0.27 vs. 0.84 ± 0.31; P = 0.031) indicating DSE-induced increased proteolysis.

CONCLUSION

HMW VWF multimer ratio represents a valuable biomarker for classical LF/LG AS subclassification and mirrors haemodynamics during DSE. HMW VWF multimer ratio identifies the TS subtype without the use of other imaging techniques.

Impact of significant paravalvular leaks after transcatheter aortic valve implantation on anaemia and mortality

OBJECTIVE

The aim of this work is to assess the relationship between significant paravalvular leak (SPL) after transcatheter aortic valve implantation (TAVI) on anaemia and their impact on prognosis.

METHODS

Observational analytic study developed at two university hospitals, including all consecutive patients who underwent TAVI during a 10-year period (2009 to 2018). A logistic regression model was created to determine independent predictors of anaemia at 3 months. Time to event outcomes were analysed with Cox regression. Median follow-up was 21.3±21.9 months.

RESULTS

788 patients were included. 5.3% had SPL. SPL was an independent predictor of anaemia 3 months after TAVI (OR: 8.31, 95% CI: 2.06 to 33.50). SPL and anaemia at 3 months were independently associated with long-term mortality (HR: 1.82, 95% CI: 1.16 to 2.85; HR: 2.07, 95% CI: 1.39 to 3.08).

CONCLUSION

SPL is an independent predictor of anaemia at 3 months after TAVI, a condition that doubles long-term mortality. Our findings could explain in part the worse prognosis of SPL after TAVI. Further pathophysiological studies are necessary to explain this association.

Pathologic Shear and Elongation Rates Do Not Cause Cleavage of Von Willebrand Factor by ADAMTS13 in a Purified System

INTRODUCTION

Pathological flows in patients with severe aortic stenosis are associated with acquired von Willebrand syndrome. This syndrome is characterized by excessive cleavage of von Willebrand factor by its main protease, A Disintegrin and Metalloproteinase with a Thrombospondin Type 1 Motif, Member 13 (ADAMTS13) leading to decreased VWF function and mucocutaneous bleeding. Aortic valve replacement and correction of the flow behavior to physiological levels reverses the syndrome, supporting the association between pathological flow and acquired von Willebrand syndrome. We investigated the effects of shear and elongational rates on von Willebrand factor cleavage in the presence of ADAMTS13.

METHODS

We identified acquired von Willebrand syndrome in five patients with severe aortic stenosis. Doppler echography values from these patients were used to develop three computational fluid dynamic (CFD) aortic valve models (normal, mild and severe stenosis). Shear, elongational rates and exposure times identified in the CFD simulations were used as parameters for the design of microfluidic devices to test the effects of pathologic shear and elongational rates on the structure and function of von Willebrand factor.

RESULTS

The shear rates (0-10,000s-1), elongational rates (0-1000 s-1) and exposure times (1-180 ms) tested in our microfluidic designs mimicked the flow features identified in patients with aortic stenosis. The shear and elongational rates tested in vitro did not lead to excessive cleavage or decreased function of von Willebrand factor in the presence of the protease.

CONCLUSIONS

High shear and elongational rates in the presence of ADAMTS13 are not sufficient for excessive cleavage of von Willebrand Factor.

Impact of Incomplete Coronary Revascularization on Late Ischemic and Bleeding Events after Transcatheter Aortic Valve Replacement

BACKGROUND

The impact of coronary artery disease (CAD) and revascularization by percutaneous coronary intervention (PCI) on prognosis in patients undergoing transcatheter aortic valve replacement (TAVR) remain debated. A dismal prognosis in patients undergoing PCI has been associated with elevated baseline SYNTAX score (bSS) and residual SYNTAX score (rSS). The objective was to investigate whether the degree of bSS and rSS impacted ischemic and bleeding events after TAVR.

METHODS

bSS and rSS were calculated in 311 patients admitted for TAVR. The primary outcome was the occurrence of major adverse cardiac events (MACE), a composite endpoint of myocardial infarction, stroke, cardiovascular death, or rehospitalization for heart failure. The occurrence of late major/life-threatening bleeding complications (MLBCs) and each primary endpoint individually were the secondary endpoints.

RESULTS

bSS > 22 was associated with higher occurrence of MACE (p = 0.013). rSS > 8 and bSS > 22 had no impact on overall cardiovascular mortality. rSS > 8 and bSS > 22 were associated with higher rates of myocardial infarction (p = 0.001 and p = 0.004) and late occurrence of MLBCs. Multivariate analysis showed that bSS > 22 (sHR 2.48) and rSS > 8 (sHR 2.35) remained predictors of MLBCs but not of myocardial infarction.

CONCLUSIONS

Incomplete coronary revascularization and CAD burden did not impact overall and cardiac mortality but constitute predictors of late MLBCs in TAVR patients.

Pre-procedural abnormal function of von Willebrand Factor is predictive of bleeding after surgical but not transcatheter aortic valve replacement

Both transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR) have been proven to effectively correct von Willebrand Factor (vWF) pathologies, however there is limited data simultaneously comparing outcomes of both approaches. We prospectively enrolled patients with severe aortic stenosis referred for TAVI (n = 52) or SAVR (n = 48). In each case, vWF antigen (vWF:Ag), vWF activity (vWF:Ac) and activity-to-antigen (vWF:Ac/Ag) ratio were assessed at baseline, 24 h and 72 h after procedure. VWF abnormalities were defined as reduced vWF:Ac/Ag ratio (< 0.8). Bleeding events in both arms were classified according to Valve Academic Research Consortium (VARC-2) definitions. Overall, there was no difference between patients referred for TAVI and SAVR in vWF:Ac (1.62 ± 0.52 vs 1.71 ± 0.64; p = 0.593), vWF:Ag (1.99 ± 0.81 vs 2.04 ± 0.81; p = 0.942) or vWF:Ac/Ag ratio (0.84 ± 0.16 vs 0.85 ± 0.12; p = 0.950). Pathological vWF:Ac/Ag ratio was found in 20 (38%) TAVI and 15 (31%) SAVR patients (p = 0.407). Normalization of vWF:Ac/Ag ratio at day 3 after procedure was achieved in 19 (95%) TAVI and 13 (87%) SAVR patients (p = 0.439). Similar prevalence of major or life-threatening bleedings (MLTB) after TAVI and SAVR in entire groups was observed (19% vs. 23%, p = 0.652). VWF abnormalities were associated with higher incidence of MLTB in SAVR (53% vs 9%, p < 0.001), but not TAVI (15% vs. 22%, p = 0.132). Accordingly, in receiver-operating characteristic curve analysis vWF:Ac/Ag ratio < 0.8 showed significant sensitivity and specificity for predicting MLTB in SAVR group (AUC 0.735, 95% CI 0.538–0.931, p = 0.019). We proved that abnormal function of vWF is corrected successfully after both TAVI and SAVR, but vWF abnormalities are predictive of MLTB only in surgical patients.

von Willebrand Factor and Management of Heart Valve Disease: JACC Review Topic of the Week

For decades, numerous observations have shown an intimate relationship between von Willebrand factor (VWF) multimer profile and heart valve diseases (HVD). The current knowledge of the unique biophysical properties of VWF helps us to understand the longstanding observations concerning the bleeding complications in patients with severe HVD. Not only does the analysis of the VWF multimer profile provide an excellent evaluation of HVD severity, it is also a strong predictor of clinical events. Also of importance, VWF responds within minutes to any significant change in hemodynamic valve status, making it an accurate marker of the quality of surgical and transcatheter therapeutic interventions. The authors provide in this review a practical, comprehensive, and evidence-based framework of the concept of VWF as a biomarker in HVD, advocating for its implementation into the clinical decision-making process besides usual clinical and imaging evaluation. They also delineate critical knowledge gaps and research priorities to definitely validate this concept.

Blood Disorders in Patients Undergoing Transcatheter Aortic Valve Replacement: A Review

Transcatheter aortic valve replacement (TAVR) is well established for treating patients with severe aortic stenosis considered at intermediate to high surgical risk. Blood disorders such as anemia, thrombocytopenia, and acquired type 2A von Willebrand disease are relatively frequent in TAVR candidates, and multiple studies to date have highlighted their potential clinical association with mortality and/or bleeding complications post-TAVR. The present review provides an overview of various blood disorders observed pre- and post-TAVR, with special focus on their incidence, etiology, clinical association, and management.

Primary Hemostatic Disorders and Late Major Bleeding After Transcatheter Aortic Valve Replacement

BACKGROUND

Periprocedural and late (>30 days) bleedings represent major complications after transcatheter aortic valve replacement and have been identified as potential areas for improved patient care.

OBJECTIVES

The authors sought to evaluate the impact of ongoing primary hemostasis disorders on late major/life-threatening bleeding complications (MLBCs).

METHODS

Bleedings were assessed according to the VARC-2 (Valve Academic Research Consortium-2) criteria. Closure time of adenosine diphosphate (CT-ADP), a surrogate marker of high molecular weight von Willebrand multimers proteolysis was assessed 24 h after the procedure. Ongoing primary hemostasis disorder was defined by a CT-ADP >180 s.

RESULTS

Among 372 patients who survived at 30 days, MLBCs occurred in 42 patients (11.3%) at a median follow-up of 383 days (interquartile range: 188 to 574 days). MLBCs were mainly of gastrointestinal origin (42.8%) and were associated with increased overall mortality (hazard ratio [HR]: 5.66; 95% confidence interval [CI]: 3.10 to 10.31; p < 0.001) and cardiac mortality (HR: 11.62; 95% CI: 4.59 to 29.37; p < 0.001). A 2.5-fold elevation of MLBCs could be evidenced in patients with a CT-ADP > 180 s (27.4% vs. 11.5%; p < 0.001). Multivariate regression analysis identified paravalvular leak (PVL) (HR: 6.31; 95% CI: 3.43 to 11.60; p < 0.0001) and CT-ADP > 180 s (HR: 3.08; 95% CI: 1.62 to 5.81; p = 0.0005) as predictor of MLBCs.

CONCLUSIONS

MLBCs after transcatheter aortic valve replacement are frequent and associated with an increased morbidity and mortality. PVL and CT-ADP >180 s were identified as strong predictors for MLBCs. These findings strongly suggest that persistent HMW defects contribute to enhanced bleeding risk in patients with residual PVL.

Turbulent Flow Promotes Cleavage of VWF (von Willebrand Factor) by ADAMTS13 (A Disintegrin and Metalloproteinase With a Thrombospondin Type-1 Motif, Member 13)

Objective—

Acquired von Willebrand syndrome is defined by excessive cleavage of the VWF (von Willebrand Factor) and is associated with impaired primary hemostasis and severe bleeding. It often develops when blood is exposed to nonphysiological flow such as in aortic stenosis or mechanical circulatory support. We evaluated the role of laminar, transitional, and turbulent flow on VWF cleavage and the effects on VWF function.

Approach and Results—

We used a vane rheometer to generate laminar, transitional, and turbulent flow and evaluate the effect of each on VWF cleavage in the presence of ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type-1 motif, member 13). We performed functional assays to evaluate the effect of these flows on VWF structure and function. Computational fluid dynamics was used to estimate the flow fields and forces within the vane rheometer under each flow condition. Turbulent flow is required for excessive cleavage of VWF in an ADAMTS13-dependent manner. The assay was repeated with whole blood, and the turbulent flow had the same effect. Our computational fluid dynamics results show that under turbulent conditions, the Kolmogorov scale approaches the size of VWF. Finally, cleavage of VWF in this study has functional consequences under flow as the resulting VWF has decreased ability to bind platelets and collagen.

Conclusions—

Turbulent flow mediates VWF cleavage in the presence of ADAMTS13, decreasing the ability of VWF to sustain platelet adhesion. These findings impact the design of mechanical circulatory support devices and are relevant to pathological environments where turbulence is added to circulation.

Transcatheter aortic valve implantation in a patient with suspected hereditary von Willebrand disease and severe gastrointestinal bleeding - a case report

INTRODUCTION

von Willebrand disease is the most common hereditary coagulopathy and is characterised by a deficiency in the quantity or quality of the von Willebrand factor. Heyde Syndrome, in contrast, is an acquired form of von Willebrand syndrome (AVWS) due to calcific aortic valve stenosis, characterised by gastrointestinal bleeding from angiodysplasia.

CASE PRESENTATION

A 73-year-old patient presented with severe gastrointestinal bleeding and stated that she suffered from hereditary von Willebrand disease. Upon echocardiography, a severe aortic valve stenosis was found, and hence the suspicion of additional AVWS was raised. Since endoscopic interventions and conservative therapeutic approaches did not result in a cessation of the bleeding, transcatheter aortic valve implantation (TAVI) was performed to stop the additional shear stress on von Willebrand factor. This resulted in cessation of the bleeding.

CONCLUSION

Retrospectively, this life-threatening gastrointestinal bleeding was a result of severe Heyde Syndrome, which could be alleviated by TAVI. Whether the patient had suffered from inherited von Willebrand disease in the past, remains uncertain. AVWS should be considered in patients with suspected inherited von Willebrand disease and concomitant severe aortic valve stenosis, since it constitutes a treatable cause of a potentially severe bleeding disorder.

Heyde Syndrome: Aortic Stenosis and Beyond

Heyde described aortic stenosis and gastrointestinal bleeding in the 1950s. Since then, a link with intestinal angiodysplasia and abnormalities of von Willebrand factor (VWF) has been noted. Loss of the highest-molecular-weight multimers of VWF and bleeding also have been described in subaortic stenosis in hypertrophic cardiomyopathy, in isolated mitral and aortic insufficiency, in endocarditis, in patients with prosthetic valve stenosis or regurgitation, and in patients with left ventricular assist devices (LVADs). Bleeding tends to recur with local treatment of angiodysplasias, whereas cardiac repair or removal of LVAD eliminates VWF dysfunction is curative of bleeding in the majority.

Acquired von Willebrand Syndrome Associated with Cardiovascular Diseases

The blood glycoprotein von Willebrand factor (VWF) plays an important role in hemostasis and thrombosis. VWF is produced and secreted as large multimers by endothelial cells and megakaryocytes. It is then cleaved in a sheer-stress dependent manner by a specific protease, ADAMTS13, into multimers consisting of 2–80 subunits. Among VWF multimers, high molecular weight (HMW) multimers play important roles in platelet aggregation. Therefore, their loss induces a hemostatic disorder known as von Willebrand disease (VWD) type 2A. Various cardiovascular diseases, such as aortic stenosis, hypertrophic obstructive cardiomyopathy (HOCM), and several congenital structural diseases, as well as mechanical circulatory support systems, generate excessive high shear stress in the bloodstream. These cause excessive cleavage of VWF multimers resulting in a loss of HMW multimers, known as acquired von Willebrand syndrome (AVWS), a hemostatic disorder similar to VWD type 2A. Bleeding often occurs in the gastrointestinal tract since a fragile angiodysplasia develops associated with these diseases. Radical treatment for AVWS is to remove the pathological high shear causing AVWS.

Rotational thromboelastometry-guided perioperative management of coagulation in a patient with Heyde's syndrome undergoing transcatheter aortic valve implantation

BACKGROUND

Changes in coagulability during the hyperacute phase within 24 h after transcatheter aortic valve implantation (TAVI) for Heyde's syndrome, or aortic stenosis complicated by gastrointestinal angiodysplasia and acquired coagulation dysfunction, have not been clarified. We evaluated perioperative changes in coagulability using rotational thromboelastometry (ROTEM).

CASE PRESENTATION

A female patient with Heyde's syndrome in her 80s underwent TAVI. ROTEM showed coagulation dysfunction before and at 6 h after surgery. Improvements in coagulation function started at 12 h after surgery. Based on ROTEM findings, oral administration of antiplatelet agents was started on the day after surgery. No hemorrhagic complications were observed in the postoperative phase.

CONCLUSIONS

Evaluation of coagulation function using ROTEM was useful for monitoring perioperative hemostasis and coagulation in this patient.

Comparison of Frequency of Late Gastrointestinal Bleeding With Transcatheter Versus Surgical Aortic Valve Replacement

Improvements in technology and operator experience have led to exponential growth of transcatheter aortic valve implantation (TAVI) programs. Late bleeding complications were recently highlighted after TAVI with a high impact on morbidity. The purpose of the present study was to assess the incidence and financial impact of late Gastrointestinal (GI) bleeding after TAVI, and compare with the surgical cohort. Retrospective analysis of the National Readmissions Database was performed from January 2011 to December 2014, and patients who underwent TAVI or surgical aortic valve replacement (SAVR) were identified. Incidence of readmission with a diagnosis of GI bleeding was utilized as the primary end point. Overall, 43,357 patients were identified who underwent TAVI, whereas 310,013 patients underwent SAVR. Compared with SAVR, TAVI patients were older (81 vs 68y, p < 0.001), more women (48% vs 36%, p < 0.001), and had higher Elixhauser Comorbidity Index (6 vs 5, p < 0.001). Hospital stay was shorter with TAVI (5 vs 8 days, p < 0.001), but raw in-hospital mortality rates were similar (4.2% vs 3.8%, p = 0.022). In the TAVI cohort, 3.3% of patients were rehospitalized for GI bleeding compared with 1.5% of the SAVR cohort (p < 0.001). Average time to bleeding readmission was similar between cohorts (92 vs 84 days, p = 0.049). After multivariable adjustment, TAVI remained significantly associated with readmissions for GI bleeding compared with SAVR Adjusted Odds Ratio (AOR 1.54 [1.38 to 1.71], p < 0.001). In this national cohort study, TAVI was associated with more frequent readmissions for late GI bleeding compared with SAVR. In conclusion, strategies to reduce late GI bleeding may serve as important targets for improvement in overall quality of care.

Thrombo-embolic prevention after transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) has emerged as a valuable treatment alternative to surgical aortic valve replacement among patients with symptomatic aortic stenosis at increased surgical risk. The rapid technological evolution from early to current-generation TAVI systems with low-profile delivery catheters, bioprosthetic valves with proven midterm durability, and improved positioning and retrieval features have made important contributions to the widespread clinical use of this minimal invasive therapy. Although peri-procedural and long-term thrombotic and bleeding events after TAVI remain a relevant concern, the optimal antithrombotic strategy and duration to mitigate these risks remain unclear. This review provides an overview of recent insights in this field, and highlights current and future antithrombotic trials focusing on optimizing outcomes in patients undergoing TAVI.

Aortic stenosis and anemia with an update on approaches to managing angiodysplasia in 2018

Angiodyplasia and aortic stenosis are both conditions that are highly prevalent in elderly people and can often co-exist. Recent studies suggest that this association is related to subtle alterations in plasma coagulation factors. The von Willebrand factor is the strongest link between aortic stenosis and bleeding associated with gastrointestinal angiodysplasia. With an ageing population, the disease burden of aortic stenosis and its association with angiodysplasia of the bowel makes this an incredibly underdiagnosed yet important condition. Clinicians should be aware of this association when dealing with elderly patients presenting either with unexplained anemia, gastrointestinal bleeding or with aortic stenosis. A high index of suspicion and appropriate diagnostic techniques followed by appropriate and prompt treatment could be life-saving. No clear guidelines exist on management but surgical aortic valve replacement is thought to offer the best hope for long-term resolution of bleeding. With a growing number of technological armamentarium in the management of such patients, especially with the advent of transcatheter aortic valve implantation, new options can be offered even to elderly patients with comorbidities for whom conventional surgery would have been impossible.

A case of recurrent obscure gastrointestinal bleeding: Heyde's syndrome - case report and review

Gastrointestinal bleeding from angiodysplasias in patients with aortic stenosis is termed as 'Heyde's syndrome'. We report a case of Heyde's syndrome successfully treated with trans-catheter aortic valve replacement.

Gastrointestinal Bleeding in Native and Prosthetic Valve Disease

Gastrointestinal bleeding with severe aortic stenosis was originally described in the 1950s by Heyde, although for years, the association was debated. Further discovery of mechanisms and the ubiquity and severity of acquired von Willebrand syndrome in the left ventricular assist device therapy have removed any doubts. At this time, gastrointestinal bleeding from intestinal angiodysplasia in patients with turbulence-related proteolysis of the highest molecular weight multimers of von Willebrand factor is now known to occur in patients with aortic stenosis, and also subaortic obstruction and associated mitral insufficiency in hypertrophic cardiomyopathy, isolated mitral and aortic insufficiency, endocarditis, and in patients with prosthetic valve dysfunction, either from stenosis or insufficiency. The degree of loss of high molecular weight multimers correlates with lesion severity, and tests of von Willebrand factor function have been proposed as important biomarkers of the severity of valve dysfunction, including in-lab testing for paravalvular leak during transcatheter aortic valve replacement. Bleeding tends to recur after endoscopic or surgical therapy, but cardiac repair is curative in the great majority.

Von Willebrand Factor as a Novel Player in Valvular Heart Disease: From Bench to Valve Replacement

von Willebrand Factor (vWF) is a well-known mediator of hemostasis and vascular inflammation. Its dynamic modulation in the bloodstream, according to hemodynamic conditions, makes it an appealing biomarker in patients with valvular heart disease (VHD). Recent studies highlight the close connection between vWF and VHD, with possible implications in the pathogenesis of VHD, promoting valve aging and calcification or favoring the development of infective endocarditis. Moreover, vWF has been recently proposed as a new diagnostic and prognostic tool in patients with valve stenosis or regurgitation, showing a strict correlation with severity of valve disease, outcome, and bleeding (Heyde syndrome). A novel role for vWF is also emerging in patients undergoing percutaneous or surgical valve repair/replacement to select and stratify patients, evaluate periprocedural bleeding risk, and detect procedural complications. We also report our single-center experience, suggesting, for the first time, possible clinical implications for vWF in percutaneous mitral valve repair (MitraClip). This review summarizes recent advances in the role of vWF in VHD with an updated overview going from bench to operating room.

Characterization of Von Willebrand Factor Multimer Structure in Patients With Severe Aortic Stenosis

Acquired von Willebrand syndrome (AVWS) associated with severe aortic stenosis (AS) has been frequently subclassified into a subtype 2A based on the deficiency of high-molecular-weight (HMW) multimers as it is seen in inherited von Willebrand disease (VWD) type 2A. However, the multimeric phenotype of VWD type 2A does not only include an HMW deficiency but also a decrease in intermediate-molecular-weight (IMW) multimers and an abnormal inner triplet band pattern. These additional characteristics have not been evaluated in AVWS associated with severe AS. Therefore, we recruited N = 31 consecutive patients with severe AS and performed a high-resolution Western blot with densitometrical band quantification to characterize the von Willebrand factor (VWF) multimeric structure and reevaluate the AVWS subtype classification. Study patients showed an isolated HMW VWF multimer deficiency without additional abnormalities of the IMW portions and the inner triplet structure in 65%. In conclusion, the multimeric pattern of AVWS associated with severe AS does neither resemble that seen in AVWS type 2A nor that seen in inherited VWD type 2A. Therefore, a subclassification into a type 2A should not be used.

Patient-prosthesis mismatch in patients treated with transcatheter aortic valve implantation - predictors, incidence and impact on clinical efficacy. A preliminary study

Introduction

Patient-prosthesis mismatch (PPM) is relatively frequent after surgical aortic valve replacement (SAVR) and negatively impacts prognosis.

Aim

We sought to determine the frequency and clinical effects of PPM after transcatheter aortic valve implantation (TAVI).

Material and methods

Overall, 238 patients who underwent TAVI were screened. Moderate PPM was defined as indexed effective orifice area (EOAi) between 0.65 and 0.85 cm²/m², and severe PPM as < 0.65 cm²/m². All-cause mortality and the Valve Academic Research Consortium 2 (VARC-2) defined composite of clinical efficacy at 1 year were the primary endpoints.

Results

Finally, 201 patients were included (mean age: 79.6 ±7.4 years, 52% females). The femoral artery served as the delivery route in 79% and most of the prostheses were self-expanding (68%). Any PPM was present in 48 (24%) subjects, and only 7 (3.5%) had severe PPM. Body surface area (BSA) independently predicted any PPM (OR = 16.9, p < 0.001) whereas post-dilation tended to protect against PPM (OR = 0.46, p = 0.09). All-cause mortality was similar in patients with moderate or severe PPM as compared to those with no PPM (14.6% vs. 14.3% vs. 13.1%, respectively, log-rank p = 0.98). Neither moderate (OR = 1.6, 95% CI: 0.8-3.2, p = 0.16) nor severe PPM (OR = 1.67, 95% CI: 0.36-7.7, p = 0.51) had a significant impact on composite endpoint, or its elements, with the exception of transvalvular pressure gradient > 20 mm Hg.

Conclusions

Severe PPM after TAVI is rare, can be predicted by larger BSA and does not seem to affect mid-term mortality or composite clinical outcome. Larger studies are needed to find different independent predictors of PPM and elucidate its impact in terms of device durability and long-term clinical efficacy.

Incidence, Predictors and Outcome of Prosthesis-Patient Mismatch after Transcatheter Aortic Valve Replacement: a Systematic Review and Meta-analysis

The aim of this study was to investigate the incidence, predictors and outcome of prosthesis-patient mismatch (PPM) following transcatheter aortic valve replacement (TAVR). A total of 30 articles incorporating 4,691 patients were identified. The pooled incidences of overall, moderate and severe PPM following TAVR were 33.0%, 25.0% and 11.0% respectively. Medtronic CoreValve (MCV) had lower incidence of overall (32% vs: 40%, P < 0.0001) and moderate (23% vs 32%, P < 0.0001) than Edwards Sapien (ESV). PPM was associated with a younger age, smaller annulus diameter and lower left ventricular ejection fraction in comparison with those patients without PPM. Post-dilation (OR, 0.51, 95% CI, 0.38 to 0.68, p < 0.001) during TAVR would decrease the incidence of PPM. Although PPM was common after TAVR, no significant differences were observed both in short- and mid-term all-cause mortality (30 day: OR: 1.1, 95% CI, 0.70 to 1.73 and 2 year: OR: 1.01, 95% CI, 0.74 to 1.38) between patients with PPM and those without PPM. In conclusion, despite being common after TAVR, the incidence of PPM was lower than that of surgical aortic valve replacement (SAVR) and decreased with the experience accumulating, and PPM was not seen to impact on short- and mid-term survival, regardless of its magnitude.

von Willebrand factor disruption and continuous-flow circulatory devices

Bleeding events remain a significant and frequent complication of continuous-flow left ventricular assist devices (VADs). von Willebrand factor (VWF) is critical to hemostasis by acting as a bridging molecule at sites of vascular injury for normal platelet adhesion as well as promoting platelet aggregation under conditions of high shear. Clinical and experimental data support a role for acquired von Willebrand disease in VAD bleeding episodes caused by shear-induced qualitative defects in VWF. Pathologic shear induces VWF unfolding and proteolysis of large multimers into smaller less hemostatic multimers via ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13). This review outlines the pathobiology of VWF disruption in the context of VADs as well as current diagnostic and management strategies of the associated acquired von Willebrand disease.