Arteriovenous Malformations Research Articles

Diagnosing Monogenic Stroke at Younger Age.

An increasing number of monogenic conditions underlying stroke are being identified. We explored the possibilities of increasing the diagnostic yield of monogenic stroke in a population under 56 years of age. Fifty probands ≤55 years at their first stroke episode were characterized clinically and investigated by whole genome sequencing. Probands had one or more of: (1) one or more first to second degree relatives with stroke under 60 years or same stroke-causing condition/disease; (2) no hypertension, hypercholesterolemia, diabetes, heart disease, or smoking; or (3) either multiple stroke episodes or multiple arterial dissections. Variants with minor allele frequency under 0.01, identified by using our stroke gene panels, were assessed. The stroke subtypes, including large artery atherosclerotic, large artery nonatherosclerotic (tortuosity, dolichoectasia, aneurysm, nonatherosclerotic dissection, or occlusion), cerebral small vessel disease, cardioembolic (arrhythmia, heart defect, or cardiomyopathy), coagulation dysfunctions (venous thrombosis, arterial thrombosis, or bleeding tendency), intracerebral hemorrhage, vascular malformations (cavernoma or arteriovenous malformations), metabolic disorders, or cryptogenic embolic, were used for genotype-phenotype correlation. In a final step, we combined genetic and clinical information to determine if the genetic variant likely was the cause of stroke in the patients. Whole genome sequencing of younger patients with stroke identified 17 clinically matching genetic variants in 15 of 50 (30%) patients, while a stronger clinical correlation with stroke was established in only 6 (12%) of them. Stroke-related genetic variants were identified in 4 of 5 (80%) patients with cardioembolic stroke subtype, 3 of 4 (75%) with intracerebral hemorrhage, 7 of 18 (39%) with cryptogenic embolic stroke, 1 of 6 (17%) with small vessel disease, and 3 of 15 (20%) of patients with nonatherosclerotic large artery stroke, including 1 of 11 (9%) with cervical dissection stroke. Careful clinical interpretation of whole genome data using stroke gene panels can detect monogenic causes of early stroke, allowing individualized follow-up and opening new possibilities for potential treatment.

Percutaneous closure of pulmonary arteriovenous malformation and concomitant patent foramen ovale for cryptogenic stroke.

Percutaneous closure of pulmonary arteriovenous malformation and concomitant patent foramen ovale for cryptogenic stroke.

CDK6-mediated endothelial cell cycle acceleration drives arteriovenous malformations in hereditary hemorrhagic telangiectasia.

Increased endothelial cell proliferation is a hallmark of arteriovenous malformations (AVMs) in hereditary hemorrhagic telangiectasia (HHT). Here, we report a cyclin-dependent kinase 6 (CDK6)-driven mechanism of cell cycle deregulation involved in endothelial cell proliferation and HHT pathology. Specifically, endothelial cells from the livers of HHT mice bypassed the G1/S checkpoint and progressed through the cell cycle at an accelerated pace. Phosphorylated retinoblastoma (pRB1)-a marker of G1/S transition through the restriction point-accumulated in endothelial cells from retinal AVMs of HHT mice and endothelial cells from skin telangiectasia samples from HHT patients. Mechanistically, inhibition of activin receptor-like kinase 1 signaling increased key restriction point mediators, and treatment with the CDK4/6 inhibitors palbociclib or ribociclib blocked increases in pRB1 and retinal AVMs in HHT mice. Palbociclib also improved vascular pathology in the brain and liver, and slowed cell cycle progression in endothelial cells and endothelial cell proliferation. Endothelial cell-specific deletion of CDK6 was sufficient to protect HHT mice from AVM pathology. Thus, clinically approved CDK4/6 inhibitors might have the potential to be repurposed for HHT.

Risk of late radiation necrosis more than 5 years after stereotactic radiosurgery.

Radiation necrosis (RN) is a well-recognized late complication most commonly occurring within 2 years of stereotactic radiosurgery (SRS); however, late RN (LRN), RN occurring or recurring > 5 years after SRS, has been poorly described. This study analyzes the incidence of and risk factors for LRN occurring > 5 years after SRS. This retrospective analysis included patients treated with linear accelerator-based SRS for tumors or arteriovenous malformations with > 5 years of clinical and serial MRI follow-up. LRN was defined as new neurological symptoms with neuroanatomically correlated imaging findings without disease recurrence. Univariate and multivariate analyses for LRN were performed using the Cox proportional hazards model. The authors identified a cumulative 297 lesions in 219 patients treated to a median dose of 17 Gy with a median follow-up of 7.4 years. In total, 290 (97.6%) lesions were treated in a single fraction, and 64 (21.5%) were treated after resection. The LRN occurred in 19 (8.7%) patients and in 23 (7.7%) lesions at a median of 6.1 years (range 5.1-13.9 years) after SRS. Fifteen of the 23 (65.2%) lesions were managed with steroids, bevacizumab, and/or antiepileptic drugs. The remaining 8 (34.8%) were resected; histopathology confirmed necrosis without disease recurrence in each. On multivariate analysis, only > 5-cm3 volume of the brain receiving 12 Gy (brain V12Gy) (HR 6.01, 95% CI 1.77-20.48; p = 0.004) and a history of early, previously resolved RN (HR 9.53, 95% CI 2.00-45.61; p = 0.005) remained significantly associated with LRN. RN risk persists well beyond 5 years after SRS, and recognizing LRN as an entity has important implications in managing these patients. LRN risk was highest in those with a brain V12Gy > 5 cm3 and a history of early RN after SRS, warranting close follow-up in perpetuity for select patients.

Imaging of the Inferior Mesenteric Vasculature.

The inferior mesenteric artery (IMA) and inferior mesenteric vein (IMV) supply and drain blood from the distal colon and rectum, respectively. Routinely imaged at cross-sectional imaging of the abdomen and pelvis, these vessels play a vital role in gastrointestinal tract health but may be neglected due to their diminutive caliber relative to other mesenteric vessels and potential lack of inclusion in routine search patterns. The authors describe and illustrate normal and abnormal appearances of the IMA and IMV and findings that are diagnostic of primary vascular abnormalities or can offer diagnostic clues. After the embryologic features, normal anatomy, and anatomic variants of the IMA and IMV are reviewed, various manifestations of IMA and IMV abnormalities, such as aneurysm and pseudoaneurysm, stenosis, occlusion, dissection, hemorrhage, arteriovenous malformations and fistulas, tumoral invasion, vasculitis, and perivascular lymphatic dilatation, are explored with use of case examples. The role of the IMA and IMV as collateral vasculature, including the clinical scenarios of superior mesenteric arterial occlusion, aortic endoleak, and portosystemic venous shunt, are discussed. Finally, diagnostic clues that the inferior mesenteric vessels and adjacent soft tissues can provide, including mesenteric venous gas, compression or displacement from bowel volvulus or internal hernias, lymphadenopathy, and venous flow artifacts, are highlighted. The authors provide a comprehensive reference for radiologists who evaluate the IMA and IMV on cross-sectional images and shine a spotlight on these neglected but important vessels. ©RSNA, 2024 Supplemental material is available for this article.

Unusual Cause of Hypoxemia during Pregnancy: New Diagnosis of Pulmonary Arteriovenous Malformations.

Unusual Cause of Hypoxemia during Pregnancy: New Diagnosis of Pulmonary Arteriovenous Malformations.

Transarterial embolization of petrosal dural arteriovenous fistula (dAVF): Feasible and successful in the post-Onyx era

Background: Intracranial dural arteriovenous fistula (dAVF) is a rare arteriovenous malformation with potentially severe complications. This study investigates the efficacy and safety of transarterial embolization (TAE) in treating petrous dAVFs through a retrospective analysis and literature review. Case Description: A retrospective analysis of six patients with petrous dAVFs treated with TAE was conducted, accompanied by a systematic literature review to evaluate treatment outcomes. Data collection included patient characteristics, clinical presentation, Borden–Shucart and Cognard classifications, treatment specifics, and overall outcomes. TAE, particularly utilizing Onyx, demonstrated favorable outcomes in our six patients. Regarding literature review results, 102 articles were identified through PubMed Mesh tool search, but only five were included after careful evaluation. In addition, one article was manually added after searching for the remaining articles. Combining our six cases with literature findings, 79.8% (n = 75) of patients undergoing TAE achieved a cure with the technique, though Onyx was reported in only 13.9% (n = 13) of TAE cases. Complications were observed in 11.7% (n = 11) of TAE cases. Conclusion: Our presented cases and literature review suggest that the TAE of dAVFs is feasible and curative for selected cases of petrous dAVFs. However, the complexity of these lesions and the availability of other treatment modalities should be taken into consideration to optimize cure rates and patient outcomes.

Venous aneurysms in unruptured supratentorial brain arteriovenous malformations: a protective factor against hemorrhagic stroke and insights into hemodynamic mechanisms.

This study endeavors to clarify the impact of venous aneurysms (VA) on hemorrhagic risk in brain arteriovenous malformations (AVMs) and uncover potential hemodynamic mechanisms, utilizing quantitative digital subtraction angiography (QDSA) technology and survival dataset. Patients were enrolled in a multicenter prospective collaboration registry between August 2011 and August 2021, and subsequently categorized into the VA and non-VA cohorts. Using propensity score-matched survival analysis, we quantitatively assessed the natural risk of hemorrhagic stroke in these two cohorts. Additionally, a quantitative hemodynamic analysis was conducted to explore the distinctions in hemodynamic characteristics between these two cohorts. Among 3758 consecutive AVMs documented at a single center from the registry, 820 unruptured AVMs who maintained conservation management over 1 month were identified. Following a two-step matching process, 504 cases were retained for survival analysis and 408 cases for hemodynamic analysis. Overall, the presence of VA emerged as a protective factor, associated with a decreased risk of hemorrhagic stroke (HR, 0.21 [95% CI: 0.07-0.62], p = 0.004). Distinct hemodynamic characteristics were observed in AVMs with VA, showing a lower stasis index in two components of AVMs-the nidus (p = 0.014) and the main draining vein (p = 0.018). In this observational prospective cohort study, the presence of VA is associated with a decreased risk of hemorrhagic stroke in AVMs, suggesting an underlying hemodynamic mechanism involving the redistribution of excessive pressure loads within the AVM nidus by the VA. Questions What impact, if any, does VA have on the hemorrhagic risk in brain AVMs? Findings Presence of VA is associated with a decreased hemorrhagic stroke risk through the redistribution of pressure loads. Critical relevance VA in brain AVMs emerges as a protective factor against hemorrhagic stroke. Understanding this association and the underlying hemodynamic mechanisms offers valuable guidance for preventive strategies and informs clinical decision-making, improving overall patient care.

MÚLTIPLOS ABSCESSOS ESPLÊNICOS EM PACIENTE COM CIRROSE HEPÁTICA NO AMAZONAS

A 38-year-old male patient with a diagnosis of liver cirrhosis for 5 years, irregularly treated with lactulose and furosemide, presented with fever, confusion, fatigue, jaundice, and ventilator-dependent pleuritic pain when seeking medical attention. Upon examination, he was lucid but exhibited slowed thinking, a sleep-wake cycle inversion, and flapping. The physical examination revealed edema in the lower limbs, jaundice, and pain in the left subcostal region. Due to the presence of decompensated cirrhosis, monitoring and diagnostic investigation for possible etiologies were initiated. Laboratory tests, ECG, chest X-ray, and echocardiogram were performed. A computed tomography (CT) scan revealed splenomegaly with regular contours and heterogeneous attenuation coefficients, showing hypodense, non-enhancing collections occupying the entire upper half, as well as a left pleural effusion and signs of chronic liver disease and portal hypertension. A transverse incision was made, revealing splenomegaly with the presence of thick fluid collections in the upper pole of the spleen, consistent with a diagnosis of splenic abscess. The patient progressed to hypovolemic shock and underwent reoperation after 72 hours for active bleeding control. Ciprofloxacin and clindamycin were administered for 28 days. The patient improved well after discharge from the ICU, with clinical and laboratory improvement. Follow-up was conducted with amoxicillin 250 mg for two years, and he continues outpatient follow-up with a gastroenterologist. Splenic abscess (SA) usually arises from endocarditis or other forms of hematogenous transmission, such as pneumonias, gastrointestinal perforations, or arteriovenous malformations. Although not always present, risk factors for the development of endocarditis include immunosuppression, diabetes mellitus, trauma, or microorganisms. Diagnosis is based on clinical findings and imaging studies (ultrasound and CT). Treatment depends on the number, size, and location of the abscesses. Antibiotic therapy can drastically reduce mortality associated with this condition, and percutaneous drainage has been successful. However, in some cases, splenectomy is necessary. Splenic abscess is a rare condition, and its early diagnosis requires a high degree of suspicion, and there is still no best approach for treatment.

An Exceptional Case of Traumatic Arteriovenous Malformation in the Chin: Clinical Insights and Implications

An Exceptional Case of Traumatic Arteriovenous Malformation in the Chin: Clinical Insights and Implications

Outcomes and management of Haemoptysis in the Fontan population

Abstract Background Patients with a Fontan circulation for palliation of a univentricular congenital heart defect commonly possess pulmonary vascular abnormalities including arteriovenous malformations (AVM), aortopulmonary and venous-venous collaterals (1). These vessels are prone to haemorrhage which may result in life-threatening haemoptysis (2). This risk is increased with oral anticoagulant medication, given to reduce the risk of thromboembolism in Fontan patients (3). Management of these patients is difficult, and strategies vary across institutions. Purpose We aim to describe our experience with managing adult Fontan patients presenting with haemoptysis in a tertiary centre with a large Fontan cohort. Methods We retrospectively reviewed the records of 410 adult Fontan patients. Individuals admitted to our institution with an episode of haemoptysis were included. Details relating to anticoagulation regimens, interventions and mortality of patients were captured. Results From a cohort of 410 Fontan patients, 35 haemorrhagic events were observed in 11 patients (2.68%). The median age at initial haemoptysis was 24.5 years (range 19 to 43 years). 6 of the 11 patients were female (54.5%). Haemoptysis recurred in 8 of the 11 patients (72.7%). 2 out of 11 had a prior history of haemoptysis in childhood. All patients were administered with oral vitamin K antagonists at presentation. 24 of the 35 events were managed conservatively with IV fluids, anticoagulation reversal and tranexamic acid (66.7%). 11 events required catheter-based interventions, with coil and/or plug embolization of bleeding vessels. Prior to intervention, CT successfully identified potential bleeding sites in 10 of the 11 events (90.9%) but could not visualise all vessels that were subsequently embolized. The most common culprits for haemoptysis were aortopulmonary collaterals, followed by AVMs and venous-venous collaterals. In severe cases, more extensive management was required including transfusions, bronchoscopy, intubation, surgical exploration (1 patient) and pneumonectomy (1 patient). 3 patients died following recurrent severe haemoptysis (27.3%), and 2 patients died of subsequent Fontan failure and sudden cardiac death respectively. Total mortality of the cohort is 5 out of 11 (45.5%) with a median follow up of 10.75 years (range 3 days to 27 years). Conclusions Haemoptysis is a rare but potentially fatal complication in patients who have undergone a Fontan procedure. The variability in presentation of this condition mandates an individualised approach to management with involvement of a multidisciplinary team. There is a high rate of recurrence following haemoptysis and a comprehensive assessment of all potential bleeding sites is necessary. CT is a useful tool to help facilitate this and guide further management. Our policy is to close all potential sources of bleeding as CT and invasive angiography rarely identifies an active point of bleeding.

A Rare Case of Pulmonary Vascular Anomaly: MDCT Pulmonary Angiography in Diagnosis of Arteriovenous Malformation and Post-operative Imaging

Objective. To demonstrate the diagnostic algorithm and tactics of a surgical management of patients with pulmonary arteriovenous malformations.Materials and Methods. Based on a patient`s clinical data analysis, further examination tactic was chosen: in the pre and postoperative periods multispiral computed tomography (MSCT) angiopulmonography (on a Canon Aquillion Prime, Japan) was performed before and after intravenous administration of a iodine-containing contrast agent (Ultravist, 370 mg/ ml) at the rate of 1 ml/kg. Brain magnetic resonance tomography was performed on a Signa Voyager, General Electric, China, 1,5 Tl in the pulse sequences T1, T2, T2 FLAIR, DWI, SWAN in three mutually perpendicular planes with a slice thickness of 1-5 mm to examine the neurological complications. Interventional angiopulmonography was implemented by using General Electric Innova IGS530, France, angiographic system before and after endovascular occluder ("AMPLATZER Vascular PLUG 4", USA) and spirals ("2D-Helical-35" 9 mm in diameter and 2,7 mm long (4 spirals) and "Complex–Helical-18" 11 mm in diameter and 17 mm long, USA) placement. A literature review in Russian and English languages for the last 5 years was searched using CyberLeninka, PubMed Central, Elibrary data bases, by keywords: pulmonary arteriovenous malformation, MSCT angiopulmonography, endovascular treatment. The prospective longitudinal study was conducted in compliance with the principles of ethics in accordance with the Helsinki Declaration, and informed voluntary consent was obtained from the patient.Results. According to clinical and instrumental data, the tactics of combined endovascular treatment of a vascular malformation with subsequent postoperative control was collectively chosen. During the curation, an increase in saturation parameters, general wellbeing improvement, decrease in pulmonary pressure parameters, and diminution in the size of the right heart's parts were achieved.Conclusion. Arteriovenous malformations (AVMs) are rare vascular abnormalities that represent a pathological communication between the arterial and venous bed. The fistulous link leads to an abnormal discharge of blood, bypassing the physiological capillary channel. Radiation and interventional visualization methods play the most important diagnostic, and the latest — therapeutic role in management of patients and are able to establish indications for surgical intervention, prevent the occurrence of life-threating complications: abscesses, paradoxical embolism and heart attacks, progressive respiratory and heart failure.

Analysis of the role of perfusion parameters in predicting rupture of brain arteriovenous malformations: a multi-center study

This study aimed to investigate the potential correlation between the perfusion parameters of brain arteriovenous malformations (bAVMs) as determined by multiphase CT angiography and bAVM rupture. Based on the occurrence of bAVM-related hemorrhage, 480 diagnosed bAVM patients were divided into hemorrhage (n = 220) and non-hemorrhage (n = 260) groups in this retrospective multi-center study spanning 2010 to 2020. On initial rupture CT images, the bAVM nidus and major draining vein were segmented, and time-density curves were extracted to compute perfusion parameters including mean transit time (MTT), time to peak (TTP), blood volume (BV), and blood flow (BF). To examine the potential correlation between these parameters and bAVM rupture, logistic regression was utilized to analyze multifactorial data and compare differences between the two groups. The ruptured group demonstrated a bAVM nidus characterized by an increased BF, a shorter TTP and MTT, and a higher peak density. The veins that were draining exhibited a reduced TTP, MTT, and peak density. A nidus TTP of less than 4s was identified by the multifactorial analysis as a critical risk factor for bAVM rupture. The statistical results highlight the noteworthy correlation between nidus TTP and bAVM rupture, presenting an original framework for assessing the risk of rupture.

Dual-energy CT angiography in detecting underlying causes of intracerebral hemorrhage: an observational cohort study.

CT angiography (CTA) is often used to detect underlying causes of acute intracerebral hemorrhage (ICH). Dual-energy CT (DECT) is able to distinguish materials with similar attenuation but different compositions, such as hemorrhage and contrast. We aimed to evaluate the diagnostic yield of DECT angiography (DECTA), compared to conventional CTA in detecting underlying ICH causes. All non-traumatic ICH patients who underwent DECTA (both arterial as well as delayed venous phase) at our center between January 2014 and February 2020 were analyzed. Conventional CTA acquisitions were reconstructed ('merged') from DECTA data. Structural ICH causes were assessed on both reconstructed conventional CTA and DECTA. The final diagnosis was based on all available diagnostic and clinical findings during one-year follow up. Of 206 included ICH patients, 30 (14.6%) had an underlying cause as final diagnosis. Conventional CTA showed a cause in 24 patients (11.7%), DECTA in 32 (15.5%). Both false positive and false negative findings occurred more frequently on conventional CTA. DECTA detected neoplastic ICH in all seven patients with a definite neoplastic ICH diagnosis, whereas conventional CTA only detected four of these cases. Both developmental venous anomalies (DVA) and cerebral venous sinus thrombosis (CVST) were more frequently seen on DECTA. Arteriovenous malformations and aneurysms were detected equally on both imaging modalities. Performing DECTA at clinical presentation of ICH may be of additional diagnostic value in the early detection of underlying causes, especially neoplasms, CVST and DVAs.

Intramuscular hemangioma capillary type with HRAS mutation: Expanding the molecular genetic spectrum with an emphasis on overlap with arteriovenous malformations and distinct from infantile hemangioma

AimsIntramuscular hemangioma capillary type (IHCT) is a rare entity that refers to fast-flow vascular lesions. This study aims to elucidate the relationships between clinicopathological, radiological, and molecular characteristics in IHCT patients. Methods and resultsWe reviewed all IHCT cases which were treated surgically in our pathology database from 2014 to 2023. Ten cases were analyzed via next-generation sequencing (NGS) and Sanger sequencing. The cohort consisted of 10 patients (6 males, 4 females) with a median age of 18 years (range: 1–37). Disease lesions were located in the trunk (n = 4), upper extremity (n = 2), lower extremity (n = 2), shoulder (n = 1), and neck (n = 1). IHCT is most commonly a progressively increasing painless mass. Histopathologically, all lesions exhibited aggregates, lobules, and anastomosing cords of capillary-type vessels separating or infiltrating the skeletal muscles. Four cases exhibited irregularly dilated vessels with thick walls, such as arteriovenous malformations (AVM) in the lesion's periphery. MRI findings commonly demonstrated a well-delineated, homogeneous mass. Somatic mutations were detected in seven of the ten IHCT cases. Four cases harbored mutations in MAP2K1 (p.Q58_E62del, p.K57_G61del, p.K57 N), two cases harbored mutations in KRAS (p.Q61R and p.L56V, p.G13R), and one case harbored a mutation in HRAS (p.D69_Q70insRWYSAMRD). Mutant allele frequencies detected by sequencing ranged from 9.98% to 15.97%. ConclusionsThe hemodynamic and molecular genetic phenotypes of IHCT closely resemble those observed in AVMs. Newly identified KRAS missense mutations, including cases with coexisting mutation types, and HRAS insertion mutations offer valuable insights into the genetic basis of vascular anomalies. These findings may also present potential targets for the development of novel pharmacotherapeutic interventions.

Pulmonary arteriovenous malformation in children.

Pulmonary arteriovenous malformations (PAVMs) are rare abnormalities observed mainly in children with hereditary haemorrhagic telangiectasia (HHT). A majority of patients are asymptomatic at the time of detection. However, complications such as hypoxemia, stroke, cerebral abscess and massive hemoptysis can arise if larger PAVMs remain untreated. Larger PAVMs are usually managed successfully with embolization, although reperfusion of PAVMs have been reported post procedure. Early screening for PAVMs is recommended in asymptomatic children with HHT or those at risk for HHT. Longer term surveillance is also essential, to enable timely identification and management of PAVMs.

Arterial-Lymphatic-Like Endothelial Cells Appear in Hereditary Hemorrhagic Telangiectasia 2 and Contribute to Vascular Leakage and Arteriovenous Malformations.

Arteriovenous malformations (AVMs) are characteristic of hereditary hemorrhagic telangiectasia. Loss-of-function mutations in the activin receptor-like kinase 1 (Alk1) are linked to hemorrhagic telangiectasia type 2. Endothelial-specific deletion of Alk1, endothelial lineage tracing, transcriptomics of single-cell analysis, and electron microscopy were performed to examine the vascular phenotype and characteristics of ALK1-deficient endothelial cells (ECs) after EC-specific Alk1 deletion. Ischemia assays were used to examine the cell capacity for vascular malformation. Connectivity Map with transcriptomic analysis was applied to identify chemical compounds. Specific methods for arteriovenous malformations, such as micro-computed tomography, with other molecular and cell biological tools were also performed. We performed endothelial-specific deletion of Alk1 in mice and found severe arteriovenous malformations and vascular leakage. The transcriptomics of single-cell analysis revealed a new distinctive cell cluster formed after Alk1 deletion where the cells coexpressed arterial and lymphatic endothelial markers. The analysis projected that these cells potentially originated from arterial ECs after Alk1 deletion. This new population was referred to as arterial-lymphatic-like ECs according to its cellular markers, and its appearance was validated in the pulmonary small arteries after Alk1 deletion. Transplantation of these cells caused vascular malformations. Endothelial lineage tracing confirmed that these new arterial-lymphatic-like ECs were derived from ALK1 depleted ECs, potentially arterial ECs. We discovered that SOX17 (SRY-box transcription factor 17) induction was responsible for the derivation of these arterial-lymphatic-like ECs. We showed that direct binding of MDM2 (mouse double minute 2) was required for Sox17 to execute this activity. Inhibition of MDM2 reduced the arteriovenous malformations in the mouse model. Together, our studies revealed the mechanistic underpinnings of ALK1 signaling in regulating the endothelial phenotype and provided possibilities for new therapeutic strategies in hemorrhagic telangiectasia type 2.

Postpartum Ultrasound: An Indispensable Tool in the Labor Ward.

Postpartum hemorrhage can occur because of different conditions. Apart from placental remnants and uterine atony, less common causes include uterine rupture, placental polyps, arteriovenous malformations, and pseudoaneurysms. Ultrasound plays a key role in the precise definition of the underlying pathology, which is necessary to initiate the appropriate therapy. It also helps to depict intraabdominal hematomas and uterine scar dehiscence, 2 conditions that do not necessarily lead to postpartum hemorrhage but are associated with increased maternal morbidity. This article presents 52 ultrasound images together with clinical and histopathologic images to give an overview of both frequent and rare pathologies in the postpartum period.

Safety and efficacy of newer liquid embolic agents squid and PHIL in endovascular embolization of cerebral arteriovenous malformations and dural arteriovenous fistulas: A systematic review and meta-analysis

Safety and efficacy of newer liquid embolic agents squid and PHIL in endovascular embolization of cerebral arteriovenous malformations and dural arteriovenous fistulas: A systematic review and meta-analysis

A case report of acute myocardial infarction with hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder characterized by epistaxis, gastrointestinal bleeding, iron deficiency anemia, and arteriovenous malformations (AVMs) affecting the lungs, liver, and brain. Owing to its rarity and diagnostic challenges, early identification is often elusive. Underdiagnosis and prolonged diagnostic delays are prevalent. Here, we present the case of a 63-year-old male who presented with chest pain and was diagnosed with an ST-elevation myocardial infarction (STEMI). Subsequently, he underwent placement of a drug-eluting stent in the right coronary artery (RCA). However, recurrent postoperative epistaxis resulted in severe anemia, prompting further investigation leading to the diagnosis of hereditary hemorrhagic telangiectasia through comprehensive medical history and genetic testing. Future studies are warranted to evaluate reperfusion strategies in HHT patients presenting with myocardial infarction.