Hereditary haemorrhagic telangiectasia and pregnancy: a review of the literature

Anaesthetic management for caesarean section in a patient with hereditary haemorrhagic telangiectasia and severe epistaxis during pregnancy

A primigravida patient, with a history of hereditary haemorrhagic telangiectasia (HHT) manifesting as nasal angiodysplasia and hepatic arteriovenous malformations (AVM), presented for delivery planning and anaesthetic evaluation at 29 weeks of gestation. She was hospitalised several times during the second and third trimester for serious recurrent epistaxis, leading to severe anaemia. In total, she required the transfusion of 20 units of packed red blood cells during her pregnancy as well as surgical nasal haemostasis under general anaesthesia (GA). The patient was referred to our tertiary centre for delivery. In the context of recurrent severe epistaxis and high cardiac output (due to hepatic AVM) in the third trimester, a multidisciplinary decision was made to plan an elective caesarean section at 35 4/7 weeks combined with nasal packing under GA. This report discusses the implications of HHT, the multidisciplinary planning of the caesarean section, intraoperative anaesthetic management and patient follow-up.

[Hereditary hemorrhagic telangiectasia]

Hereditary hemorrhagic telangiectasia, also known as Rendu-Osler - Weber disease, is a rare, autosomal dominant vascular disease, with prevalence of 1/5,000. The condition is characterized by muco-cutaneous telangiectasias, which are responsible for a hemorrhagic syndrome of variable severity, as well as arteriovenous malformations (AVMs) appearing in the lungs, the liver, and the nervous system. They can be the source of shunts, which may be associated with high morbidity (neurological ischemic stroke, brain abscess, high-output heart failure, biliary ischemia…). It is therefore crucial to establish a clinical diagnosis using the Curaçao criteria or molecular diagnosis based on genetic analysis of the ENG, ACVRL1, SMAD4 and GDF2 genes. In most cases, multidisciplinary management allows patients to have normal life expectancy. Advances in interventional radiology and better understanding of the pathophysiology of angiogenesis have resulted in improved therapeutic management. Anti-angiogenic treatments, such as bevacizumab (BVZ, an anti-VEGF antibody), have proven to be effective in cases involving bleeding complications and severe liver damage with cardiac repercussions. Other anti-angiogenic agents are currently being investigated, including tyrosine kinase inhibitors.

Hereditary Hemorrhagic Telangiectasia in Pediatric Age: Focus on Genetics and Diagnosis

Hereditary Hemorrhagic Telangiectasia (HHT) or Rendu-Osler-Weber Syndrome (ROW) is an autosomal dominant vascular disease, with an estimated prevalence of 1:5000. Genes associated with HHT are ACVRL1, ENG, SMAD4, and GDF2, all encoding for proteins involved in the TGFβ/BMPs signaling pathway. The clinical diagnosis of HHT is made according to the "Curaçao Criteria," based on the main features of the disease: recurrent and spontaneous epistaxis, muco-cutaneous telangiectases, arteriovenous malformations in the lungs, liver, and brain, and familiarity. Since the clinical signs of HHT can be misinterpreted, and the primary symptom of HHT, epistaxis, is common in the general population, the disease is underdiagnosed. Although HHT exhibits a complete penetrance after the age of 40, young subjects may also present symptoms of the disease and are at risk of severe complications. Here we review the literature reporting data from clinical, diagnostic, and molecular studies on the HHT pediatric population.

Update on pulmonary arteriovenous malformations

This review aimed to provide an overview of pulmonary arteriovenous malformations, including the major clinical and radiological presentations, investigation, and treatment algorithm of the condition. The primary etiology of pulmonary arteriovenous malformations is hereditary hemorrhagic telangiectasia (HHT), also known as Rendu-Osler-Weber syndrome, with mutations in the ENG gene on chromosome 9 (HHT type 1) or in the ACVRL1/ALK1 complex (HHT type 2). Epistaxis should always be evaluated when repeated, when associated with anemia, and in some cases of hypoxemia. In the investigation, contrast echocardiography and chest CT are essential for evaluating this condition. Embolization is the best treatment choice, especially for correction in cases of hypoxemia or to avoid systemic infections. Finally, disease management was addressed in special conditions such as pregnancy. CT follow-up should be performed every 3-5 years, depending on the size of the afferent and efferent vessels, and antibiotic prophylactic care should always be oriented. Ultimately, knowledge of the disease by health professionals is a crucial point for the early diagnosis of these patients in clinical practice, which can potentially modify the natural course of the disease.

Spontaneous haemothorax caused by a ruptured pulmonary arterio-venous malformation: A manifestation of hereditary haemorrhagic telangiectasia in pregnancy

We report our experience of managing a massive haemothorax caused by a ruptured, previously unknown, pulmonary arteriovenous malformation (pAVM) at 34 + 5 weeks of gestation, which proved to be a manifestation of hereditary haemorrhagic telangiectasia (HHT), also known as Osler–Weber–Rendu syndrome. The patient underwent an emergency caesarean section under general anaesthesia after placement of a chest tube and gave birth to a healthy infant. A postoperative thoracic computed tomography angiography highlighted the presence of the large pAVM. Transcatheter embolization was performed right after the delivery. Subsequent patient's anamnesis, family history and genetic analysis finally revealed the presence of the syndrome. The aim of our report is to create awareness of this serious condition with potential life-threatening complications, especially in pregnancy. Simple criteria have been published and allow to easily consider HHT and the presence of potential AVM during anamnesis, ideally even before pregnancy.

Whole genome sequences discriminate hereditary hemorrhagic telangiectasia phenotypes by non-HHT deleterious DNA variation

The abnormal vascular structures of hereditary hemorrhagic telangiectasia (HHT) often cause severe anemia due to recurrent hemorrhage, but HHT causal genes do not predict the severity of hematological complications. We tested for chance inheritance and clinical associations of rare deleterious variants in which loss-of-function causes bleeding or hemolytic disorders in the general population. In double-blinded analyses, all 104 patients with HHT from a single reference center recruited to the 100 000 Genomes Project were categorized on new MALO (more/as-expected/less/opposite) sub-phenotype severity scales, and whole genome sequencing data were tested for high impact variants in 75 HHT-independent genes encoding coagulation factors, or platelet, hemoglobin, erythrocyte enzyme, and erythrocyte membrane constituents. Rare variants (all gnomAD allele frequencies <0.003) were identified in 56 (75%) of these 75 HHT-unrelated genes. Deleteriousness assignments by Combined Annotation Dependent Depletion (CADD) scores >15 were supported by gene-level mutation significance cutoff scores. CADD >15 variants were identified in 38/104 (36.5%) patients with HHT, found for 1 in 10 patients within platelet genes; 1 in 8 within coagulation genes; and 1 in 4 within erythrocyte hemolytic genes. In blinded analyses, patients with greater hemorrhagic severity that had been attributed solely to HHT vessels had more CADD-deleterious variants in platelet (Spearman ρ = 0.25; P = .008) and coagulation (Spearman ρ = 0.21; P = .024) genes. However, the HHT cohort had 60% fewer deleterious variants in platelet and coagulation genes than expected (Mann-Whitney test P = .021). In conclusion, patients with HHT commonly have rare variants in genes of relevance to their phenotype, offering new therapeutic targets and opportunities for informed, personalized medicine strategies.

Uncommon Female-Predominant Etiologies of Cryptogenic Stroke

The etiologies of cryptogenic stroke are complex and heterogeneous. A number of uncommon etiologies are not fully recognized, some of which predominantly affect females. Most of these etiologies are closely related to the hormonal level, reproductive factors, coagulation function, and medications of females. Moreover, once cryptogenic stroke is diagnosed, females tend to have worse outcomes. Therefore, prompt etiological recognition and treatment are crucial for good recovery. The aim of this article is to review advances in exploring uncommon female-predominant etiologies of cryptogenic stroke. These etiologies are categorized into arterial, cardiac, and venous sources. Arterial vasoconstrictive narrowing, intimal injury, and intimal developmental abnormality can cause brain ischemia or artery-to-artery cerebral embolism. Myocardial contraction dysfunction, cardiac wall injury, and developmental abnormality can induce intracardiac thrombosis and lead to cardiac embolism. In addition, cortical venous thrombosis and occult venous thromboembolism via intracardiac or extracardiac channels also account for cryptogenic stroke in females. Due to the lack of knowledge, in clinical practice, the above etiologies are seldom assessed. The low incidence rate of these etiologies can lead to missed diagnosis. This review will provide novel clinical clues for the etiological diagnosis of cryptogenic stroke and will help to improve the management and secondary prevention of stroke in the female population. In the future, more studies are needed to explore the etiology and prevention strategies of cryptogenic stroke.

HHT-Related Epistaxis and Pregnancy-A Retrospective Survey and Recommendations for Management from an Otorhinolaryngology Perspective

Appropriate management of hereditary hemorrhagic telangiectasia (HHT) is of particular importance in females, as HHT-mediated modifications of the vascular bed and circulation are known to increase the risk of complications during pregnancy and delivery. This study was undertaken to evaluate female HHT patients’ awareness of and experience with HHT during pregnancy and delivery, with a focus on epistaxis. In this retrospective study, 46 females (median age: 60 years) with confirmed HHT completed a 17-item questionnaire assessing knowledge of HHT and its pregnancy-associated complications, the severity of epistaxis during past pregnancies and deliveries, and the desire for better education and counselling regarding HHT and pregnancy. Results revealed that 85% of participants were unaware of their disease status prior to the completion of all pregnancies. Further, 91% reported no knowledge of increased pregnancy-related risk due to HHT. In regard to epistaxis, 61% of respondents reported experiencing nosebleeds during pregnancy. Finally, approximately a third of respondents suggested that receiving counseling on the risks of HHT in pregnancy could have been helpful. Findings suggest that awareness of HHT and its potential for increasing pregnancy-related risk is poor. Best practices in HHT management should be followed to minimize negative effects of the disorder.

Hereditary haemorrhagic telangiectasia with atrial septal defect and pulmonary hypertension during advanced pregnancy: a case report and literature review

Pregnancy complicated with hereditary haemorrhagic telangiectasia (HHT) is a rare condition. This case report presents an extremely rare case with the co-occurrence of HHT and congenital heart disease. In this report, a 43-year-old woman at 36 + 4 weeks of gestation experienced haemoptysis with a volume of approximately 300 ml for the first time. Uncommonly, her transthoracic echocardiogram revealed a previously unrecognized atrial septal defect (ASD) and pulmonary hypertension (PH) for the first time at 36 + 1 weeks of gestation. Chest computed tomography revealed an arteriovenous malformation (AVM) in the right lower lobe of the lung. Due to concerns of rebleeding of ruptured pulmonary arteriovenous malformations (PAVMs), the patient underwent a caesarean section at 36 + 6 weeks of gestation. A healthy male infant weighing 2800 g was delivered. To the best of our knowledge, there have been few reports about HHT with ASDs and PH during advanced pregnancy. This current case report highlights the necessity for clinicians to pay considerable attention to cardiac structural abnormalities, which can worsen PAVM in patients with HHT during pregnancy, for whom terminating the pregnancy in time may reduce the risk of PAVM rupture.

Ischemic Stroke and Pulmonary Arteriovenous Malformations: A Review

The potential of covert pulmonary arteriovenous malformations (PAVMs) to cause early onset, preventable ischemic strokes is not well known to neurologists. This is evident by their lack of mention in serial American Heart Association/American Stroke Association (AHA/ASA) Guidelines and the single case report biased literature of recent years. We performed PubMed and Cochrane database searches for major studies on ischemic stroke and PAVMs published from January 1, 1974, through April 3, 2021. This identified 24 major observational studies, 3 societal guidelines, 1 nationwide analysis, 3 systematic reviews, 21 other review/opinion articles, and 18 recent (2017-2021) case reports/series that were synthesized. Key points are that patients with PAVMs have ischemic stroke a decade earlier than routine stroke, losing 9 extra healthy life-years per patient in the recent US nationwide analysis (2005-2014). Large-scale thoracic CT screens of the general population in Japan estimate PAVM prevalence to be 38/100,000 (95% confidence interval 18-76), with ischemic stroke rates exceeding 10% across PAVM series dating back to the 1950s, with most PAVMs remaining undiagnosed until the time of clinical stroke. Notably, the rate of PAVM diagnoses doubled in US ischemic stroke hospitalizations between 2005 and 2014. The burden of silent cerebral infarction approximates to twice that of clinical stroke. More than 80% of patients have underlying hereditary hemorrhagic telangiectasia. The predominant stroke mechanism is paradoxical embolization of platelet-rich emboli, with iron deficiency emerging as a modifiable risk factor. PAVM-related ischemic strokes may be cortical or subcortical, but very rarely cause proximal large vessel occlusions. Single antiplatelet therapy may be effective for secondary stroke prophylaxis, with dual antiplatelet or anticoagulation therapy requiring nuanced risk-benefit analysis given their risk of aggravating iron deficiency. This review summarizes the ischemic stroke burden from PAVMs, the implicative pathophysiology, and relevant diagnostic and treatment overviews to facilitate future incorporation into AHA/ASA guidelines.

A missed case of hereditary hemorrhagic telangiectasia: A case report

Hereditary hemorrhagic telangiectasia is a rare autosomal dominant disorder characterized by abnormal blood vessel formation. When an abnormal vascular architecture affects the lungs and central nervous system, serious complications can occur. We report a missed case of hereditary hemorrhagic telangiectasia with pulmonary arteriovenous malformations and cerebral arteriovenous malformations. A 22-year-old Chinese female was taken to the emergency room because of unconsciousness. Emergency head contrast-enhanced computed tomography and transthoracic contrast echocardiography showed that she had cerebral arteriovenous malformations and pulmonary arteriovenous malformations. The patient experienced multiple spontaneous epistaxis since childhood, for which she was treated at a local hospital for a brief period. Her mother also had pulmonary arteriovenous malformations. The patient was diagnosed with hereditary hemorrhagic telangiectasia according to the consensus Curaçao diagnostic criteria and eventually died of hereditary hemorrhagic telangiectasia. The case report highlights the importance of early diagnosis and intervention for hereditary hemorrhagic telangiectasia. Given that hereditary hemorrhagic telangiectasia is frequently undiagnosed, increasing the physician’s awareness of hereditary hemorrhagic telangiectasia can play an important role in the timely diagnosis and treatment of these patients.

The European Rare Disease Network for HHT Frameworks for management of hereditary haemorrhagic telangiectasia in general and speciality care

Hereditary haemorrhagic telangiectasia (HHT) is a complex, multisystemic vascular dysplasia affecting approximately 85,000 European Citizens. In 2016, eight founding centres operating within 6 countries, set up a working group dedicated to HHT within what became the European Reference Network on Rare Multisystemic Vascular Diseases. By launch, combined experience exceeded 10,000 HHT patients, and Chairs representing 7 separate specialties provided a median of 24 years' experience in HHT. Integrated were expert patients who focused discussions on the patient experience. Following a 2016-2017 survey to capture priorities, and underpinned by more than 40 monthly meetings, and new data acquisitions, VASCERN HHT generated position statements that distinguish expert HHT care from non-expert HHT practice. Leadership was by specialists in the relevant sub-discipline(s), and 100% consensus was required amongst all clinicians before statements were published or disseminated. One major set of outputs targeted all healthcare professionals and their HHT patients, and include the new Orphanet definition; Do's and Don'ts for common situations; Outcome Measures suitable for all consultations; COVID-19; and anticoagulation. The second output set span aspects of vascular pathophysiology where greater understanding will assist organ-specific specialist clinicians to provide more informed care to HHT patients. These cover cerebral vascular malformations and screening; mucocutaneous telangiectasia and differential diagnosis; anti-angiogenic therapies; circulatory interplays between anaemia and arteriovenous malformations; and microbiological strategies to counteract loss of normal pulmonary capillary function. Overall, the integrated outputs, and documented current practices, provide frameworks for approaches that augment the health and safety of HHT patients in diverse health-care settings.

Hereditary hemorrhagic telangiectasia (HHT): a practical guide to management

Hereditary hemorrhagic telangiectasia (HHT), the second most common inherited bleeding disorder, is associated with the development of malformed blood vessels. Abnormal blood vessels may be small and cutaneous or mucosal (telangiectasia), with frequent complications of bleeding, or large and visceral (arteriovenous malformations [AVMs]), with additional risks that can lead to significant morbidity and even mortality. HHT can present in many different ways and can be difficult to recognize, particularly in younger patients in the absence of a known family history of disease or epistaxis, its most common manifestation. HHT is commonly diagnosed using the established Curaçao clinical criteria, which include (1) family history, (2) recurrent epistaxis, (3) telangiectasia, and (4) visceral AVMs. Fulfillment of 3 or more criteria provides a definite diagnosis of HHT, whereas 2 criteria constitute a possible diagnosis of HHT. However, these criteria are insufficient in children to rule out disease due to the age-dependent development of some of these criteria. Genetic testing, when positive, can provide definitive diagnosis of HHT in all age groups. Clinical course is often complicated by significant epistaxis and/or gastrointestinal bleeding, leading to anemia in half of adult patients with HHT. The management paradigm has recently shifted from surgical approaches to medical treatments aimed at control of chronic bleeding, such as antifibrinolytic and antiangiogenic agents, combined with aggressive iron replacement with intravenous iron. Guidelines for management of HHT, including screening and treatment, were determined by expert consensus and originally published in 2009 with updates and new guidelines in 2020.

Imaging Manifestations and Interventional Treatments for Hereditary Hemorrhagic Telangiectasia

Hemorrhagic hereditary telangiectasia (HHT) is a rare autosomal dominant disorder that causes multisystem vascular malformations including mucocutaneous telangiectasias and arteriovenous malformations (AVMs). Clinical and genetic screening of patients with signs, symptoms, or a family history suggestive of HHT is recommended to confirm the diagnosis on the basis of the Curaçao criteria and prevent associated complications. Patients with HHT frequently have epistaxis and gastrointestinal bleeding from telangiectasias. Pulmonary AVMs are common right-to-left shunts between pulmonary arteries and veins that can result in dyspnea and exercise intolerance, heart failure, migraine headaches, stroke or transient ischemic attacks, brain abscesses, or in rare cases, pulmonary hemorrhage. Primary neurologic complications from cerebral AVMs, which can take on many forms, are less common but particularly severe complications of HHT. Multimodality imaging, including transthoracic echocardiography, Doppler US, CT, and MRI, is used in the screening and initial characterization of vascular lesions in patients with HHT. Diagnostic angiography is an important tool in characterization of and interventional treatments for HHT, particularly those in the lungs and central nervous system. A multidisciplinary approach to early diagnosis, treatment, imaging, and surveillance at high-volume HHT Centers of Excellence is recommended. Although a variety of idiopathic, traumatic, or genetic conditions can result in similar clinical and imaging features, the Curaçao criteria are particularly useful for the proper diagnosis of HHT. Imaging and treatment options are reviewed, with a focus on screening, diagnosis, and posttreatment findings, with the use of updated international guidelines. Online supplemental material is available for this article. ^©RSNA, 2021.

Hereditary haemorrhagic telangiectasia: development of a regional life-course collaborative clinical care pathway

Hereditary haemorrhagic telangiectasia is a rare, genetic disorder that can present at any age. It is characterised by epistaxis, mucocutaneous telangiectasia and visceral arteriovenous malformations, which can affect multiple organs. Early diagnosis and management reduces the morbidity and mortality associated with the disease. There is a well-established hereditary haemorrhagic telangiectasia clinic in London, and excellent links across Europe via the European Reference Network. However, local coordinated care for patients with hereditary haemorrhagic telangiectasia across the UK can be variable and often absent for children and young people. Some patients travel long distances to receive care in London, while others are referred to local clinicians or lost to follow up entirely. This article presents the experience to date from two regional UK centres (Liverpool and Dundee) where care for patients with hereditary haemorrhagic telangiectasia is being coordinated and streamlined. While there is still a lot to learn, this article highlights some of the successes and challenges identified so far, with suggestions for how these could be addressed. Collaborative regional networks such as these can facilitate the sharing of best practice and ensure that all patients with hereditary haemorrhagic telangiectasia are able to access safe, high-quality care.

Massive haemorrhagic complications of ruptured pulmonary arteriovenous malformations: outcomes from a 12 years' retrospective study

Background

The life-threatening haemorrhagic complications of pulmonary arteriovenous malformations (PAVMs) are extremely rare, and only described in isolated cases. This study was designed to comprehensively investigate management of ruptured PAVMs.

Methods

We retrospectively assessed clinical and imaging data of ruptured PAVMs to summarize incidence, clinical characteristics, and outcomes following embolisation between January 2008 and January 2021.

Results

Eighteen of 406 (4.4%) patients with PAVMs developed haemorrhagic complications. Twelve of 18 patients were clinically diagnosed with hereditary haemorrhagic telangiectasia (HHT). Haemorrhagic complications occurred with no clear trigger in all cases. Eight of 18 patients (44.4%) were initially misdiagnosed or had undergone early ineffective treatment. 28 lesions were detected, with 89.3% of them located in peripheral lung. Computed tomography angiography (CTA) showed indirect signs to indicate ruptured PAVMs in all cases. Lower haemoglobin concentrations were associated with the diameter of afferent arteries in the ruptured lesions. Successful embolotherapy was achieved in all cases. After embolotherapy, arterial oxygen saturation improved and bleeding was controlled (P < 0.05). The mean follow-up time was 3.2 ± 2.5 years (range, 7 months to 10 years).

Conclusions

Life threatening haemorrhagic complications of PAVMs are rare, they usually occur without a trigger and can be easily misdiagnosed. HHT and larger size of afferent arteries are major risk factors of these complications. CTA is a useful tool for diagnosis and therapeutic guidance for ruptured PAVMs. Embolotherapy is an effective therapy for this life-threatening complication.

Pulmonary arterial venous malformations as primary manifestation of gestational trophoblastic neoplasia

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A unique initial presentation of GTN as pulmonary arteriovenous malformations.

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Metastatic GTN presenting as multiple visceral AVMs in the brain, liver, and lungs.

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Management of metastatic GTN with brain metastases with induction chemotherapy.

Approach to Pulmonary Arteriovenous Malformations: A Comprehensive Update

Pulmonary arteriovenous malformations (PAVMs) are abnormal direct vascular communications between pulmonary arteries and veins which create high-flow right-to-left shunts. They are most frequently congenital, usually in the setting of hereditary hemorrhagic telangiectasia (HHT). PAVMs may be asymptomatic or present with a wide variety of clinical manifestations such as dyspnea, hypoxemia, or chest pain. Even when asymptomatic, presence of PAVMs increases patients' risk of serious, potentially preventable complications including stroke or brain abscess. Transcatheter embolotherapy is considered the gold standard for treatment of PAVMs. Though previous guidelines have been published regarding the management of PAVMs, several aspects of PAVM screening and management remain debated among the experts, suggesting the need for thorough reexamination of the current literature. The authors of this review present an updated approach to the diagnostic workup and management of PAVMs, with an emphasis on areas of controversy, based on the latest literature and our institutional experience.