Pulmonary arteriovenous malformations

Large pulmonary arteriovenous malformation lost to follow-up with 10 years of asymptomatic interval growth: A case report

Pulmonary arteriovenous malformations, previously considered a rare condition, have been increasingly identified in asymptomatic patients over the past 2 decades. Usually congenital and associated with hereditary hemorrhagic telangiectasia, these fistulae result in right-to-left shunting of blood by abnormal communication of pulmonary arteries and veins lacking capillary beds. Clinical findings of right-to-left shunting in the presence of feeding and draining vessels identified on imaging confirm the diagnosis, for which the first-line therapy is embolization. This report highlights the presentation and management of a large asymptomatic PAVM detected incidentally in a patient who was lost to follow-up for 10 years and represented with acute hypoxic respiratory failure secondary to a viral infection with an interval increase of PAVM size.

Efficacy and Safety of Venous Sac Embolization With or Without Feeding Artery Embolization Versus Feeding Artery Embolization Alone in the Management of Pulmonary Arteriovenous Malformations: A Systematic Review and Meta-analysis

PURPOSE

To evaluate by meta-analysis the safety and efficacy of venous sac embolization (VSE) with or without feeding artery embolization versus feeding artery embolization (FAE) alone in the management of pulmonary arteriovenous malformations (PAVMs).

METHODS

This systematic review and meta-analysis was performed and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A systematic literature search was performed in MEDLINE, Embase, and Scopus till August 31, 2021 to identify studies comparing the safety and efficacy of VSE with or without FAE versus FAE alone in PAVMs. The success of treatment was assessed by comparing the number of PAVMs with ≥70% decrease in the size of draining vein/sac between the 2 groups. The pooled odds ratio (OR) and 95% confidence interval (95% CI) were calculated using the random-effects inverse-variance model and were used to compare pooled therapeutic efficacy between the groups.

RESULTS

Three studies were found eligible for the meta-analysis. The included studies had a total of 169 patients (119 females and 50 males). The total number of PAVMs was 298, and hereditary hemorrhagic telangiectasia was present in 119 patients. The success of treatment was higher with VSE as compared to FAE (OR=3.54, 95% CI=1.66-7.56). The minor complications were similar in both groups, and one major complication occurred in the FAE group. More coils were used in the VSE group.

CONCLUSIONS

The present systematic review and meta-analysis has consolidated the evidence that VSE with or without FAE is more efficacious than FAE alone in the management of PAVMs without any increase in the associated risk of sac rupture or coil migration.

CLINICAL IMPACT

Until high-quality data from a prospective, multicentric, randomized controlled trial becomes available, the evidence consolidated by the present systematic review and meta-analysis showing the efficacy of venous sac embolization (with or without feeding artery embolization) over feeding artery embolization alone, can be used for clinical decision-making in the management of pulmonary arterio-venous malformations.

Ultra-low dose chest CT for the diagnosis of pulmonary arteriovenous malformation in patients with hereditary hemorrhagic telangiectasia

PURPOSE

The purpose of this study was to compare ultra-low dose (ULD) and standard low-dose (SLD) chest computed tomography (CT) in terms of radiation exposure, image quality and diagnostic value for diagnosing pulmonary arteriovenous malformation (AVM) in patients with hereditary hemorrhagic telangiectasia (HHT).

MATERIALS AND METHODS

In this prospective board-approved study consecutive patients with HHT referred to a reference center for screening and/or follow-up chest CT examination were prospectively included from December 2020 to January 2022. Patients underwent two consecutive non-contrast chest CTs without dose modulation (i.e., one ULD protocol [80 kVp or 100 kVp, CTDIvol of 0.3 mGy or 0.6 mGy] and one SLD protocol [140 kVp, CTDIvol of 1.3 mGy]). Objective image noises measured at the level of tracheal carina were compared between the two protocols. Overall image quality and diagnostic confidence were scored on a 4-point Likert scale (1 = insufficient to 4 = excellent). Sensitivity, specificity, positive predictive value and negative predictive value of ULD CT for diagnosing pulmonary AVM with a feeding artery of over 2 mm in diameter were calculated along with their 95% confidence intervals (CI) using SLD images as the standard of reference.

RESULTS

A total of 44 consecutive patients with HHT (31 women; mean age, 42 ± 16 [standard deviation (SD)] years; body mass index, 23.2 ± 4.5 [SD] kg/m2) were included. Thirty-four pulmonary AVMs with a feeding artery of over 2 mm in diameter were found with SLD images versus 35 with ULD images. Sensitivity, specificity, predictive positive value, and predictive negative value of ULD CT for the diagnosis of PAVM were 100% (34/34; 95% CI: 90-100), 96% (18/19; 95% CI: 74-100), 97% (34/35; 95% CI: 85-100) and 100% (18/18; 95% CI: 81-100), respectively. A significant difference in diagnostic confidence scores was found between ULD (3.8 ± 0.4 [SD]) and SLD (3.9 ± 0.1 [SD]) CT images (P = 0.03). No differences in overall image quality scores were found between ULD CT examinations (3.9 ± 0.2 [SD]) and SLD (4 ± 0 [SD]) CT examinations (P = 0.77). Effective radiation dose decreased significantly by 78.8% with ULD protocol, with no significant differences in noise values between ULD CT images (16.7 ± 5.0 [SD] HU) and SLD images (17.7 ± 6.6 [SD] HU) (P = 0.07).

CONCLUSION

ULD chest CT provides 100% sensitivity and 96% specificity for the diagnosis of treatable pulmonary AVM with a feeding artery of over 2 mm in diameter, leading to a 78.8% dose-saving compared with a standard low-dose protocol.

Personalised stroke evaluation and management: tailoring individualised patient care for hereditary haemorrhagic telangiectasia

SummaryHereditary haemorrhagic telangiectasia (HHT) has an estimated prevalence of 1 in 5000-8000 individuals globally with pulmonary arteriovenous malformations (PAVMs) affecting approximately 15%-50% of HHT patients. Ischaemic stroke is a known complication of PAVMs that affects ≤30% of patients with PAVMs. Studies have shown that patients with PAVMs have ischaemic stroke a decade earlier than routine stroke. The predominant mechanism of ischaemic stroke in HHT patients is paradoxical embolism due to PAVMs, but most HHT-related PAVMs are asymptomatic. Additionally, HHT is often underdiagnosed in patients and poses a challenge to physicians due to its rarity. We present a case of a patient with ischaemic stroke who was subsequently diagnosed with HHT and found to have a PAVM on further evaluation. This case highlights the importance of using an individualised patient-centred stroke evaluation and screening for PAVMs in patients who had a stroke with possible or suspected HHT and definite HHT.

Psoralen: a narrative review of current and future therapeutic uses

Psoralen is a family of naturally occurring photoactive compounds found in plants that acquire potential cytotoxicity when activated by specific frequencies of electromagnetic waves. Psoralens penetrate the phospholipid cellular membranes and insert themselves between the pyrimidines of deoxyribonucleic acid (DNA). Psoralens are initially biologically inert and acquire photoreactivity when exposed to certain classes of electromagnetic radiation, such as ultraviolet light. Once activated, psoralens form mono- and di-adducts with DNA, leading to marked cell apoptosis. This apoptotic effect is more pronounced in tumor cells due to their high rate of cell division. Moreover, photoactivated psoralen can inhibit tyrosine kinase signaling and influence the immunogenic properties of cells. Thus, the cytotoxicity of photoactivated psoralen holds promising clinical applications from its immunogenic properties to potential anti-cancer treatments. This narrative review aims to provide an overview of the current understanding and research on psoralen and to explore its potential future pharmacotherapeutic benefits in specific diseases.

Don't skip a beat! Critical findings in imaging studies performed in adults with congenital heart disease

With ongoing advances in both medical and surgical management, the population of adults with congenital heart disease (CHD) continues to grow each year and has surpassed the number of pediatric cases. These adult patients will present to adult emergency departments with increasing frequency. Adults with CHD are at increased risk of developing not only cardiovascular complications, such as aortic dissection and thromboemboli, but also abdominopelvic and neurologic processes at younger ages. These individuals are also more likely to develop less urgent but clinically significant complications including end-organ dysfunction, baffle leaks, or bleeding collateral vessels. Ultimately, imaging can play a critical role in determining the triage, diagnosis, and management of adult CHD patients. To accomplish this goal, radiologists must be able to distinguish acute and chronic complications of treated CHD from benign processes, including expected post-surgical changes or imaging artifacts. Radiologists also need to be familiar with the various long-term risks and complications associated with both treated and untreated forms of CHD, particularly those in adults with complex lesions.

Hereditary hemorrhagic telangiectasia: from signaling insights to therapeutic advances

Hereditary hemorrhagic telangiectsia (HHT) is an inherited vascular disorder with highly variable expressivity, affecting up to 1 in 5,000 individuals. This disease is characterized by small arteriovenous malformations (AVMs) in mucocutaneous areas (telangiectases) and larger visceral AVMs in the lungs, liver, and brain. HHT is caused by loss-of-function mutations in the BMP9-10/ENG/ALK1/SMAD4 signaling pathway. This Review presents up-to-date insights on this mutated signaling pathway and its crosstalk with proangiogenic pathways, in particular the VEGF pathway, that has allowed the repurposing of new drugs for HHT treatment. However, despite the substantial benefits of these new treatments in terms of alleviating symptom severity, this not-so-uncommon bleeding disorder still currently lacks any FDA- or European Medicines Agency-approved (EMA-approved) therapies.

Embolization of De Novo Pulmonary Arteriovenous Malformations Using High-Volume Detachable Non-Fibered Coils: Propensity-Matched Comparison to Traditional Coils

Embolization of de novo pulmonary arteriovenous malformations (PAVMs) using high-volume detachable non-fibered (HVDNF) coils was compared to traditional non-HVDNF coils. Persistent-occlusion rates were evaluated. A total of 272 de novo (previously untreated) PAVM treatments were retrospectively stratified into those treated with non-HVDNF coils only (n = 192) and those treated with HVDNF coils with or without other coils (n = 80). Propensity score matching, followed by survival analysis and cost analysis, was performed. The overall persistent-occlusion rate was 86.0% (234/272). Persistent occlusion was achieved in 81.8% of PAVMs using non-HVDNF coils, compared with 96.3% using HVDNF coils (p = 0.0017). The mean follow-up was 30.7 ± 31.9 months versus 14.7 ± 13.4 months, respectively (p < 0.0001). Propensity-matched survival analysis demonstrated PAVMs treated with HVDNF coils recurred significantly less frequently than PAVMs treated with non-HVNDF coils (p = 0.023). The use of HVDNF coils was more expensive than standard coils, however not significantly different for the treatment of complex PAVMs. The use of high-volume detachable non-fibered coils was associated with higher persistent-occlusion rates when compared with non-HVDNF coils. HVDNF coils were more expensive on average; however, cost was similar between groups for the treatment of complex PAVMs.

Oral manifestations and dental considerations of patients with hereditary hemorrhagic telangiectasia: a scoping review

OBJECTIVE

We examined the range, nature, and extent of research conducted regarding the oral and dental implications of hereditary hemorrhagic telangiectasia (HHT) to identify gaps in the research and knowledge of the field.

STUDY DESIGN

We performed a scoping review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews and 2017 Guidance for the Conduct of Joanna Briggs Institute Scoping Reviews. We searched the MEDLINE and Web of Science databases for all full-text articles published in English from December 1946 to October 2022.

RESULTS

We identified 103 articles describing oral and dental considerations of patients with HHT, primarily case reports. Most reported oral telangiectasias of the tongue, lips, and palate. Many reported management of bleeding and the use or recommendation of prophylactic antibiotics before dental procedures.

CONCLUSIONS

Oral telangiectasias are commonly found in patients with hereditary hemorrhagic telangiectasia, and dental professionals may be the first to diagnose it in their patients. Early detection and diagnosis are important to prevent potentially fatal outcomes, and prophylactic antibiotics before procedures may be warranted.

Pulmonary arteriovenous malformation and a concurrent patent ductus arteriosus in a Doberman

A 7-week-old male Doberman presented with tachypnea, dyspnea and a VI/VI, left cranial, continuous heart murmur. Thoracic radiographs revealed severe left-sided cardiomegaly, presence of a rounded soft tissue opacity in the caudodorsal aspect of the thoracic cavity and signs of left-sided congestive heart failure. Clinical signs of heart failure were medically controlled. Echocardiography and computed tomography demonstrated a left-to-right shunting patent ductus arteriosus (PDA) in combination with a right-to-left shunting pulmonary arteriovenous malformation (PAVM) between the right main pulmonary artery and the right caudal pulmonary vein. Arterial blood gasses revealed mild hypoxemia. Transcatheter occlusion of the PDA using an Amplatz Canine Duct Occluder was performed. Four months post-operatively, echocardiography showed normal cardiac size and function with complete PDA closure. Thoracic radiographs revealed absence of the rounded opacity and resolution of cardiomegaly and vascular congestion. The PAVM was no longer visualized on repeated computed tomography and the arterial blood gasses were within normal limits. A PAVM connecting a pulmonary artery to a pulmonary vein has only rarely been reported in dogs. This report describes the presence of a congenital PAVM in combination with a PDA in a dog, which has not been previously reported in veterinary medicine.

Pre-operative embolization of a complex systemic to pulmonary vascular malformation

A 38-year-old male patient presenting with mild exertional dyspnea was noted to have a lingular opacity on chest radiograph. CT of the chest demonstrated an unusual complex inferior lingular vascular malformation with branches arising from the left internal thoracic artery and the left inferior diaphragmatic artery via the celiac artery. There was suspected communication with both pulmonary arterial and venous branches. Following thorough assessment and comprehensive clinical investigation, the patient elected to proceed to definitive surgical management due to potential risk of life-threatening hemoptysis. Interventional radiology performed pre-operative diagnostic angiography and embolization of the systemic feeding arteries. The patient proceeded to have an uncomplicated video-assisted thoracoscopic surgery segmentectomy and was discharged the next day. The patient was asymptomatic at follow-up with complete resolution of the malformation on CT at 6 months. We discuss an uncommon pathology which benefited from multidisciplinary management including successful pre-operative endovascular embolization.

Pulmonary hypertension in hereditary hemorrhagic telangiectasia: A clinical review

Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant hereditary disorder characterized by recurrent spontaneous epistaxis, mucocutaneous telangiectasias, and solid organ arteriovenous malformations (AVMs). Pulmonary hypertension (PH) is an increasingly recognized complication in patients with HHT, most often precipitated by high-output heart failure in the presence of hepatic AVMs as well as pulmonary arterial hypertension in the form of a proliferative vasculopathy. The presence of PH in patients with HHT is associated with significant elevations in rates of morbidity and mortality. Additionally, there is growing recognition of a thromboembolic propensity in this population that increases the risk of chronic thromboembolic PH, posing unique clinical considerations regarding the use of anticoagulation. Patients with HHT are also at risk of PH due to disorders commonly seen in the general population, including left-sided heart and lung disease. The etiology of PH in HHT is multifaceted and complex; the diagnostic approach and treatment strategies must consider the underlying pathophysiology of HHT. This comprehensive review summarizes current knowledge of PH in HHT, detailing the pathogenesis of known etiologies, diagnostic evaluation, and suggested treatment modalities as well as emerging therapies that may be of future interest.

Positive Bubble Study But No Evidence of Interatrial Defect in a Patient with Recurrent Cryptogenic Stroke

Pulmonary arteriovenous malformations (PAVMs) can be asymptomatic or result in a range of complications such as brain abscesses or cryptogenic emboli, which can contribute to morbidity and mortality if not diagnosed and treated in a timely manner. To date, there have been several reports of delayed diagnosis of PAVMs, which have been largely attributed to the misconception that PAVMs are too rare to be of clinical significance. Furthermore, because intracardiac shunting secondary to a patent foramen ovale (PFO) or atrial septal defect (ASD) also results in a positive saline contrast study with echocardiography, PAVM can be easily misdiagnosed as an intracardiac right-toleft shunt. However, there are unique echocardiographic features that differentiate between intracardiac shunting due to a PFO or ASD and extracardiac shunting such as in PAVM. This case details the course of a patient with recurrent cryptogenic strokes that was initially misattributed to a PFO and was only correctly diagnosed with multiple PAVMs after two failed attempts at PFO closure. This case serves as a reminder of an alternative etiology of right-to-left shunt and its presentation on imaging, which echocardiographers must be familiar with.

Evaluation of causal heart diseases in cardioembolic stroke by cardiac computed tomography

Cardioembolic stroke is a potentially devastating condition and tends to have a poor prognosis compared with other ischemic stroke subtypes. Therefore, it is important for proper therapeutic management to identify a cardiac source of embolism in stroke patients. Cardiac computed tomography (CCT) can detect the detailed visualization of various cardiac pathologies in the cardiac chambers, interatrial and interventricular septum, valves, and myocardium with few motion artifacts and few dead angles. Multiphase reconstruction images of the entire cardiac cycle make it possible to demonstrate cardiac structures in a dynamic manner. Consequently, CCT has the ability to provide high-quality information about causal heart disease in cardioembolic stroke. In addition, CCT can simultaneously evaluate obstructive coronary artery disease, which may be helpful in surgical planning in patients who need urgent surgery, such as cardiac tumors or infective endocarditis. This review will introduce the potential clinical applications of CCT in an ischemic stroke population, with a focus on diagnosing cardioembolic sources using CCT.

Neglected intrapulmonary arteriovenous anastomoses: A comparative study of pulmonary right-to-left shunts in patients with patent foramen ovale

Objective

Pulmonary right-to-left shunt (P-RLS) and patent foramen ovale right-to-left shunt (PFO-RLS) often appear in combination, and there are often differences and connections between them. Intrapulmonary arteriovenous anastomoses (IPAVAs), as part of P-RLS, are often overlooked because there are no technologies to detect and identify them. This study aimed to further clarify the incidence and characteristics of P-RLS with the help of contrast transesophageal echocardiography (c-TEE) and contrast transthoracic echocardiography (c-TTE), providing a reference for clinically relevant research and patent foramen ovale (PFO) management disposal decisions.

Methods

We retrospectively investigated 414 subjects who came to our hospital for c-TEE from October 2021 to July 2022, and all subjects completed c-TTE simultaneously. 7 Patients who were newly diagnosed with an atrial septal defect were excluded. Eventually, 407 patients were included in this study. Among them, 157 patients with PFO (58 patients were treated with PFO closure subsequently) and 250 patients without PFO confirmed by c-TEE were finally enrolled. In the process, we observed and analysed the presence of P-RLS.

Results

A total of 407 patients were included in the final analysis and divided into PFO group (N = 157) and non-PFO group (N = 250) according to the results of c-TEE. Whether at rest or after Valsalva maneuver, the incidence of P-RLS was significantly higher under c-TEE than under c-TTE in the two groups (P &lt; 0.001). For both c-TTE and c-TEE, the incidence of P-RLS was slightly higher after Valsalva maneuver than at rest, but the difference was not significant (c-TTE: rest vs. Valsalva maneuver, P = 0.214; c-TEE: rest vs. Valsalva maneuver, P = 0.076). The Valsalva maneuver increased the incidence of P-RLS in the group without PFO, which was more significant in c-TEE (c-TTE: rest vs. Valsalva maneuver, P = 0.591; c-TEE: rest vs. Valsalva maneuver, P = 0.008). In both groups, the P-RLS semiquantitative grading was statistical significance under different states and examinations (P &lt; 0.001).

Conclusion

The vast majority of P-RLS are grade 1–2 and are derived from physiological IPAVAs. Even so, attention should be given to the differentiation between P-RLS and PFO-RLS. c-TEE is an effective method to detect P-RLS; however, the recruitments of c-TEE and Valsalva maneuver to P-RLS should be noted.

Multidisciplinary coordinated care of hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu disease)

Hereditary hemorrhagic telangiectasia (HHT), also known as Osler-Weber-Rendu disease, is a rare disorder with a case prevalence as high as one in 5000, causing arteriovenous malformations in multiple organ systems. HHT is familial with autosomal dominant inheritance, with genetic testing allowing confirmation of the diagnosis in asymptomatic kindreds. Common clinical manifestations are epistaxis and intestinal lesions causing anemia and requiring transfusions. Pulmonary vascular malformations predispose to ischemic stroke and brain abscess and may cause dyspnea and cardiac failure. Brain vascular malformations can cause hemorrhagic stroke and seizures. Rarely, liver arteriovenous malformations can cause hepatic failure. A form of HHT can cause juvenile polyposis syndrome and colon cancer. Specialists in multiple fields may be called to care for one or more aspects of HHT, but few are familiar with evidence-based guidelines for HHT management or see a sufficient number of patients to gain experience with the unique characteristics of the disease. Primary care physicians and specialists are often unaware of the important manifestations of HHT in multiple systems and the thresholds for their screening and appropriate management. To improve familiarity, experience, and coordinated multisystem care for patients with HHT, the Cure HHT Foundation, which advocates for patients and families with this disease, has accredited 29 centers in North America with designated specialists for the evaluation and care of patients with HHT. Team assembly and current screening and management protocols are described as a model for evidence-based, multidisciplinary care in this disease.

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 Hemothorax by Pulmonary Arteriovenous Malformation during Pregnancy

Background:  Pulmonary arteriovenous malformation (PAVM) is a rare vascular malformation that may cause hemothorax, especially during pregnancy. Case Description:  A 25-year-old woman presented sudden-onset left chest pain, dizziness, and dyspnea in the 27th week of gestation. Computed tomography angiography showed left pleural effusion with complete hemithorax opacification and an aneurysmal PAVM. She exhibited hemorrhagic shock and received emergency exploratory video-assisted thoracic surgery. A ruptured PAVM was identified and stopped by wedge resection in the upper lobe of the left lung. The patient's postoperative clinical course was uncomplicated. She subsequently delivered a healthy live baby vaginally at 41 weeks gestation. Conclusion:  PAVM should be considered in pregnant women with hemothorax. Emergency thoracoscopic surgery is the best treatment option.

Application of contrast-enhanced ultrasound in hemothorax of hereditary hemorrhagic telangiectasia: A case report and literature review

Hereditary hemorrhagic telangiectasis (HHT) is an autosomal dominant hereditary disease, which can lead to abnormal angiogenesis. We performed contrast-enhanced ultrasound (CEUS) in a patient with HHT represented with hemothorax. After targeted embolization, the condition of hemothorax improved. In this case, we explore the use of CEUS to locate the responsible vessel of hemothorax, and found that CEUS could be used as a complementary preoperative method of localization with Computed tomography angiography (CTA).

Spontaneous hemothorax in pregnant patient with pulmonary arteriovenous malformation

We present a case of a 34-year-old pregnant patient at 26 weeks' gestation by in vitro fertilization with past medical history of hypertension and infertility who presented to the hospital with abdominal pain. The patient stated her pain was in her left upper quadrant. The morning before arriving to the hospital the patient stated she woke up at 0300 with increasingly severe pain in the same area. A computed tomography angiogram of the chest demonstrated a left-sided pulmonary arteriovenous malformation with adjacent complex left effusion on chest suspicious for a hemothorax. The hemothorax was thought to be brought about by rupture of the arteriovenous malformation with likely intermittent small volume hemorrhages into the pleural space. Thoracic Surgery and Interventional radiology (IR) were each consulted for management of the arteriovenous malformation. Due to the patient's stable hemodynamic status and concern that an invasive procedure might enable a larger rupture and more substantial hemorrhage, the decision was made for embolization of the arteriovenous malformation.

Risk factors for cerebral complications in patients with pulmonary arteriovenous malformations: A multicenter retrospective cohort study

OBJECTIVE

Pulmonary arteriovenous malformation (PAVM) is a rare pulmonary disease. Although most patients with PAVMs are asymptomatic, cerebral complications associated with PAVMs are often fatal. This study aimed to evaluate the risk factors for cerebral complications in patients with PAVMs.

METHODS

We retrospectively reviewed the medical charts of patients with PAVMs between 2003 and 2021 at two tertiary referral hospitals and one secondary hospital.

RESULTS

Fifty-five patients diagnosed with PAVMs were enrolled in this study. Most patients were female (89.1%), and the median age was 53 years. Thirty patients (54.5%) had incidentally detected PAVMs without symptoms. Twenty-four patients (43.7%) with PAVMs were treated with embolotherapy or surgery. Thirteen patients (23.6%) had cerebral complications. There was no significant difference in the development of cerebral complications according to treatment; however, older age (≥ 65 years) was associated with the development of new cerebral complications in untreated patients with PAVMs (odds ratio, 17.09; 95% confidence interval, 1.16-250.31; P = 0.038).

CONCLUSION

Older age (≥ 65 years) was a risk factor for the development of cerebral complications in patients with PAVMs; therefore, treatment should be considered in older patients with PAVMs.

Spontaneous Hemothorax during pregnancy: A case report

Introduction and importance

Spontaneous hemothorax is a rare but life-threatening condition, which is the main cause of respiratory distress during pregnancy and after delivery without any evidence of post-traumatic injury.

Case presentation

A 34-year-old woman, pregnant at 20 weeks, presented in the emergency department complaining of dyspnea accompanied by epigastric pain, with dominance on the left side. Chest X-ray and CT-scan revealed an opacity by displacing heart to the right side. Considering, there was a probability of bleeding from venous arterial malformation. Inappropriate cervical condition two days after the patient appeared thermodynamically stable a cesarean section was performed.

Clinical discussion

Pregnancy leads to increasing the size of AVM by rising cardiac output and hypoxia. Patients who are predisposed to PAVM and intend to be pregnant should be evaluated a priori.

Conclusion

Although the hemothorax is a rare phenomenon during pregnancy, management of fetus following this critical condition requires multidisciplinary assessment.

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A 34-year-old woman, pregnant at 20 weeks, presented in the emergency department complaining of dyspnea

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A chest tube was inserted in the left hemi thorax at the Emergency department.

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Although the hemothorax is a rare phenomenon during pregnancy, management of fetus following this critical condition requires multidisciplinary assessment.

Pulmonary Arteriovenous Malformations: What the Interventional Radiologist Should Know

Pulmonary arteriovenous malformations (PAVMs) are abnormal connections between the pulmonary artery and pulmonary vein bypassing the normal capillary bed causing a right-to-left shunt. The majority (80-90%) of PAVMs are associated with hereditary hemorrhagic telangiectasia (HHT). PAVMs may be asymptomatic or present with symptoms of hypoxia, shortness of breath, migraines, sequelae of paradoxical embolization, or rupture. Transcatheter embolization has become the standard of care. This article will review the clinical presentation, workup, genetics, imaging findings, embolization, complications, and follow-up for patients with PAVMs.

It's Not All in Your Head: Thoracic Manifestations of Neurologic Diseases and Disorders

Myriad conditions may affect both the neurologic system and the thorax, while other diseases primarily affecting the thorax may manifest with neurologic abnormalities. Correlation of signs, symptoms, and imaging findings in the neurological system with those in the thorax can help diagnose certain conditions and/or guide further diagnostic work-up and treatment. We will review and illustrate the imaging appearance of several systemic/neurological diseases with thoracic manifestations as well as discuss conditions in the thorax that can lead to neurologic symptoms.

Management of pulmonary arteriovenous malformations involves additional factors aside from the diameter of feeding arteries: a 3-year case-case retrospective analysis

Background

Pulmonary arteriovenous malformations (PAVMs) are rare but cause various manifestations. Although the diameter of feeding arteries has been linked to treatment decisions, relationships among the characteristics of PAVMs, clinical symptoms, and treatment effect remain unclear. The present study was performed to investigate how collective characteristics of PAVMs relate to clinical symptoms and to provide proper treatment recommendations for patients with PAVMs.

Methods

We retrospectively analysed 838,447 patients’ radiographic data and medical records from January 2018 to December 2020. Patients were included if a PAVM was radiographically detected for the first time in our hospital. Ordered multivariable logistic regression and hierarchical multiple regression were performed to analyse the relationships between characteristics of PAVMs and various clinical symptoms. We investigated the management of PAVMs in four tertiary university hospitals.

Results

Detection rate of PAVMs was 0.025% (207/838,447), and 37.6% of patients (78/207) also had hereditary haemorrhagic telangiectasia. Eight patients were diagnosed with bilateral diffuse PAVMs. Two hundred thirty-six lesions were detected in 199 patients, and the mean diameter of the feeding artery was 4.13 ± 1.92 mm. Most PAVMs were the simple type and located in the peripheral pulmonary area. In total, 34.3% of patients (71/207) were symptom-free; remaining patients showed various manifestations, and respiratory symptoms were most common (dyspnoea on exertion, 47.8%). The diameter of the feeding artery and the type and the number of PAVMs were correlated with hypoxaemia (P < 0.001, P < 0.001, and P = 0.037, respectively). The collective characteristics of PAVMs were not related to the severity of central nervous system symptoms (largest diameter of feeding artery, P = 0.8; largest diameter of sac, P = 0.42; number of PAVMs, P = 0.35; type of PAVMs, P = 0.99). Various symptoms were greatly relieved after treatment. The hospital investigation showed that management of PAVMs was not generally appreciated in clinical practice.

Conclusions

Our study revealed a low detection rate of PAVMs and a low degree of association with hereditary haemorrhagic telangiectasia in the general population. Considering the connection between collective characteristics of PAVMs and various clinical symptoms, clinicians should consider the type and number of PAVMs, the largest diameter of the feeding artery, and clinical symptoms when managing patients with PAVMs.

Silent persistent left superior vena cava right-to-left shunt as a unique cause of recurrent brain abscesses

We present a novel case of recurrent brain abscesses found to be the result of a silent congenital right-to-left extra-cardiac shunt, a persistent left superior vena cava (PLSVC) draining into the left atrium. The patient’s brain abscess was evacuated surgically, treated with antibiotics, and his shunt was subsequently repaired. The case suggests that attention should be paid to evaluation for shunt physiology allowing for bypass of the pulmonary circulation in those with recurrent brain abscesses.

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.

Automated identification of pulmonary arteries and veins depicted in non-contrast chest CT scans

We present a novel integrative computerized solution to automatically identify and differentiate pulmonary arteries and veins depicted on chest computed tomography (CT) without iodinated contrast agents. We first identified the central extrapulmonary arteries and veins using a convolutional neural network (CNN) model. Then, a computational differential geometry method was used to automatically identify the tubular-like structures in the lungs with high densities, which we believe are the intrapulmonary vessels. Beginning with the extrapulmonary arteries and veins, we progressively traced the intrapulmonary vessels by following their skeletons and differentiated them into arteries and veins. Instead of manually labeling the numerous arteries and veins in the lungs for machine learning, this integrative strategy limits the manual effort only to the large extrapulmonary vessels. We used a dataset consisting of 120 chest CT scans acquired on different subjects using various protocols to develop, train, and test the algorithms. Our experiments on an independent test set (n = 15) showed promising performance. The computer algorithm achieved a sensitivity of ∼98% in labeling the pulmonary artery and vein branches when compared with a human expert's results, demonstrating the feasibility of our computerized solution in pulmonary artery/vein labeling.

Intracardiac versus extracardiac shunt in a young man with ischaemic stroke

A 24-year-old man with a history of recent ischaemic stroke was diagnosed with patent foramen ovale (PFO) and referred for closure at our hospital. At admission, besides low peripheral oxygen saturation (88%), physical examination was otherwise normal. We performed intraprocedural transoesophageal echocardiogram that revealed no PFO, although agitated saline injection demonstrated bubbles lately on the left atrium. The atrial septum could not be crossed. We suspected an extracardiac shunt, so pulmonary angiograms were performed that revealed the presence of a left pulmonary arteriovenous malformation (PAVM). A Konar-MF Occluder was used to occlude the PAVM, with a satisfactory result. At 6 months follow-up, the patient had normal peripheral oxygen saturation and a new pulmonary angiogram showed no residual shunt. Intrapulmonary shunts are a rare and under-recognised cause of paradoxical emboli in young patients; physicians should be aware of this diagnosis as percutaneous occlusion is indicated and critical to avoid recurrent ischaemic episodes.

Identification and validation of a novel pathogenic variant in GDF2 (BMP9) responsible for hereditary hemorrhagic telangiectasia and pulmonary arteriovenous malformations

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant multisystemic vascular dysplasia, characterized by arteriovenous malformations (AVMs), mucocutaneous telangiectasia and nosebleeds. HHT is caused by a heterozygous null allele in ACVRL1, ENG, or SMAD4, which encode proteins mediating bone morphogenetic protein (BMP) signaling. Several missense and stop-gain variants identified in GDF2 (encoding BMP9) have been reported to cause a vascular anomaly syndrome similar to HHT, however none of these patients met diagnostic criteria for HHT. HHT families from UK NHS Genomic Medicine Centres were recruited to the Genomics England 100,000 Genomes Project. Whole genome sequencing and tiering protocols identified a novel, heterozygous GDF2 sequence variant in all three affected members of one HHT family who had previously screened negative for ACVRL1, ENG, and SMAD4. All three had nosebleeds and typical HHT telangiectasia, and the proband also had severe pulmonary AVMs from childhood. In vitro studies showed the mutant construct expressed the proprotein but lacked active mature BMP9 dimer, suggesting the mutation disrupts correct cleavage of the protein. Plasma BMP9 levels in the patients were significantly lower than controls. In conclusion, we propose that this heterozygous GDF2 variant is a rare cause of HHT associated with pulmonary AVMs.

A Rare Case of Upper Gastrointestinal Bleeding: Osler-Weber-Rendu Syndrome

Osler-Weber-Rendu disease, also known as hereditary hemorrhagic telangiectasia (HHT), is a rare, autosomal dominant condition that affects approximately 1 in 5000 patients causing abnormal blood vessel formation. HHT patients have mucocutaneous telangiectasias and arteriovenous malformations in various organs. The most prominent symptom of HHT is epistaxis, which, together with gastrointestinal bleeding, may cause iron deficiency anemia. This study is a case report of a 62-year-old patient who was admitted to the Department of Gastroenterology due to acute upper gastrointestinal bleeding and a history of recurrent epistaxis and melena for 4 days, which was confirmed in digital rectal examination. Urgent upper gastrointestinal endoscopy revealed active bleeding from multiple angioectatic spots with bright-looking salmon-colored patches in the antrum and the body suggestive of HHT. The bleeding from two angioectatic spots was stopped by argon plasma coagulation, and four clips were placed to provide good hemostasis. The patient was treated with a proton pomp inhibitor infusion and iron infusion. She was discharged with no signs of GI bleeding, normalized iron levels and a diagnosis of HHT. She was referred to further genetic testing, including evaluation of first-degree relatives. She also had performed unenhanced thin-cut computed tomography (CT) with angiography to exclude the presence of pulmonary arteriovenous malformations (PAVMs). Due to the fact that the patient did not manifest any other HHT-related symptoms and that the instrumental screening discloses no silent AVMs in other organs, the “watch-and-wait strategy” was applied. Although, Osler-Weber-Rendu syndrome is widely described in the medical literature, effective treatment of gastrointestinal telangiectasias is not always available and still lacks standardization to date, which makes the management of gastroenterological involvement still a challenging issue.

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.

Acquired pulmonary arteriovenous malformation associated with bronchiectasis: a case report

Background

Pulmonary arteriovenous malformations are mostly caused by congenitally abnormal shunts between pulmonary arteries and pulmonary veins.

Case presentation

A 74-year-old Japanese woman with a history of bronchiectasis was admitted to our hospital because of dyspnea on exertion. Pulmonary angiography and reconstructed three-dimensional contrast-enhanced computed tomography images showed shunts between pulmonary arteries and pulmonary veins, indicating a diagnosis of pulmonary arteriovenous malformations. Coil embolization of the shunts was successful.

Conclusions

Our findings imply that bronchiectasis can cause pulmonary arteriovenous malformations, and thus patients who present with hypoxemia with bronchiectasis should be carefully evaluated.

Imaging to intervention: a review of what the Interventionalist needs to Know about Hereditary Hemorrhagic Telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is a disorder that affects 1 in 5000-10,000 people worldwide and can result in devastating complications such as cerebral abscess, stroke, massive hemorrhage, and even death. HHT is an autosomal dominant disorder that leads to the formation of abnormal communication between the arteries and veins with a resultant spectrum of vascular anomalies. The disorder affects many organ systems and thus requires a dedicated multidisciplinary approach. Interventional radiologists are vital members of this team providing expertise not only in disease management, but in complex embolotherapy, helping to maintain the health of these patients. This article reviews clinical manifestations, screening guidelines, diagnostic criteria, and endovascular management of HHT.

Pulmonary arteriovenous malformation as a cause of ischaemic stroke in the elderly

Pulmonary arteriovenous malformation (PAVM) is well recognised as a cause of paradoxical brain embolism. The authors report the case of an older woman with a medical history of arterial hypertension who was found unconscious and was discovered to have pulmonary thromboembolism and ischaemic stroke related to a PAVM.

Successful treatment of bilateral multiple pulmonary arteriovenous malformations in a patient with brain abscess and severe hypoxemia using a combination of transcatheter embolotherapy and surgical resection: a case report

Background

A pulmonary arteriovenous malformation is an abnormal dilated blood vessel that makes direct communication between a pulmonary artery and pulmonary vein and can be associated with hypoxemia or neurological complications, including brain abscess and cerebral infarction. Treatment of pulmonary arteriovenous malformation includes surgical resection and transcatheter embolotherapy, however the adaptation of therapies should be considered when a patient is in bad condition.

Case presentation

A 51-year-old man was admitted after developing fever, consciousness disorder, and hypoxemia. Magnetic resonance imaging of the brain showed a brain abscess. Bilateral pulmonary arteriovenous malformations were found by contrast computed tomography. Because of a family history of pulmonary arteriovenous malformation, a history of epistaxis, and the existence of oral mucosa telangiectasia, he was diagnosed with hereditary hemorrhagic telangiectasia and brain abscess caused by intrapulmonary right-to-left shunt. The brain abscess improved with antibiotic treatment; however, the administration of oxygen did not ameliorate his hypoxemia. His hypoxemia was exacerbated by positive pressure ventilation. Considering his systemic and respiratory condition, we considered surgery to involve a high degree of risk. After controlling his brain abscess and pneumonia, transcatheter embolotherapy was performed. This improved his systemic condition, enabling surgical treatment.

Conclusions

This middle-aged patient suffering from brain abscess and severe hypoxemia with multiple pulmonary arteriovenous malformations was successfully treated by a combination of transcatheter embolotherapy and surgery. The adaptation and combination of therapies, as well as the sequence of treatments, should be considered depending on the patient status and lesions.

Cryptogenic Stroke Caused by Pulmonary Arterial Venous Malformation with Massive Right-to-Left Shunt: A Case Report

Background

Pulmonary arterial venous malformation (PAVM) is an abnormal vascular malformation between pulmonary arteries and veins characterized by varying degrees of right-to-left shunts (RLS). Cryptogenic stroke (CS) due to paradoxical embolism (PE) caused by PAVM is relatively rare in the clinic.

Case Presentation

We report the case of a 54-year-old right-handed woman who presented with sudden-onset left-sided limb weakness for 2 h. A physical examination revealed normal vital signs but weakness in her left upper and lower limbs, graded as 1/5 using the Medical Research Council scale. Her National Institutes of Health Stroke Scale (NIHSS) score was 8, and her modified Rankin scale (mRS) was 4. Brain diffusion-weighted imaging showed acute infarction in the right basal ganglia and the radiation crown but brain magnetic resonance angiography found no obvious abnormality. A transcranial Doppler ultrasound with bubble study (TCD-b) found the rain curtain sign of microbubbles in the left middle cerebral artery, reflecting significant RLS. Transesophageal echocardiography (TEE) and transthoracic echocardiography (TTE) were conducted to distinguish between intra- and extracardiac shunts. A pulmonary computerized tomography angiogram (CTA) demonstrated a PAVM. We considered the patient had CS due to PE caused by PAVM. Thrombolytic therapy within the time window was performed. Then, transcatheter device occlusion of the arteriovenous fistula was successfully undertaken, and the patient carried on with rehabilitation training. At a 15-month follow-up, there were no catheter-related complications or recurrent stroke, and her NIHSS and mRS scores were both 0.

Conclusions

PAVM is an important risk factor for PE and CS and should not be ignored as a possible etiology in stroke patients without any other risk factors. CTA of the pulmonary artery is the recommended gold standard for diagnosing and locating a PAVM. Thrombolytic therapy within the time window combined with transcatheter device occlusion of arteriovenous malformation and rehabilitation training may benefit the recovery of patients with CS caused by PE resulting from PAVM.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40120-021-00275-y.

Systemic arteriopulmonary venous fistula (APVF): case presentation of an asymptomatic individual and a review of the literature

Abnormal communications between the systemic and pulmonary venous systems are rare but can present as a opacity on chest radiograph. A solitary vessel communicating as a fistula directly between the systemic arterial circulation and the pulmonary venous system is not widely described. These may have significant implications in the long-term cardiovascular health of an individual acting as a left to right shunt. There is no clear consensus as to the management, but surgical management and endovascular embolisation have been successfully used. We present a case where a systemic arteriaopulmonary fistula originating from the abdominal aorta and connecting to the right inferior pulmonary vein manifested as an incidental finding on a chest radiograph and was further evaluated on cross-sectional imaging in a young patient. Chest radiographs are non-specific and it is important to be aware of the less frequent but important pathologies that can be picked up on plain chest radiographs, which inturn should warrant further investigation. This is presented in conjunction with a review of the available literature along with a discussion regarding the differential diagnosis and management applicable to the general clinician.

Multiple strokes due to pulmonary arteriovenous malformation

We present a case of recurrent strokes in a patient with absent left internal carotid artery (ICA) and pulmonary arteriovenous malformation. Pulmonary arteriovenous malformations (PAVMs) are abnormal communications between pulmonary artery and pulmonary vein, cause extracardiac right to left shunting of blood and are known to significantly increase the risk of stroke primarily due to paradoxical embolization. They are often hereditary and are commonly associated with hereditary hemorrhagic telangiectasias (HHT). Delayed bubbles seen in the left ventricle (after 3 cardiac cycles) on transthoracic echocardiogram with bubble study is often the first clue to the presence of PAVMs. CT scan of the chest can confirm the diagnosis. Percutaneous embolotherapy is the treatment of choice with reduction in stroke risk post embolization.

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.

Applicability of Transthoracic Contrast Echocardiography for the Diagnosis and Treatment of Idiopathic Pulmonary Arteriovenous Malformations

Objective: To explore the preferred test to screen for pulmonary arteriovenous malformations (PAVMs) and to predict the probability of interventional embolization. Methods: We performed a retrospective observational study evaluating patients with idiopathic PAVMs from 2009 to 2019. After clinical evaluation, a total of 105 patients were studied, including 71 patients with positive digital subtraction pulmonary angiography (DSPA) findings and 34 with negative DSPA findings. The following patient data were assessed: blood test, chest radiograph, transthoracic contrast echocardiography (TTCE), and DSPA findings. Results: The majority of patients with idiopathic PAVMs were female (66.2% with positive DSPA findings). We found a good κ-coefficient of 0.77 with strong consistency for inter observer agreement concerning the pulmonary right-to-left shunt (RLS) grade on TTCE, which was superior to conventional chest radiographs. The positive predictive value (PPV) of the radiographic features for PAVMs on DSPA was 0.83 (95% CI 0.64-1.0) and 0.44 for the possibility of embolization (95% CI 0.19-0.70). The PPV of the shunt grade of PAVMs on DSPA was 0.14 (95% CI 0.01-0.29) for grade 1, 0.74 (95% CI 0.60-0.88) for grade 2, and 0.97 (95% CI 0.92-1.0) for grade 3. The PPVs of pulmonary shunt grades 2 and 3 on TTCE for the possibility of embolization for PAVMs were 0.21 (95% CI, 0.05-0.36) and 0.87 (95% CI, 0.79-0.99), respectively. Conclusion: TTCE is the preferred screening test for PAVMs. The pulmonary RLS grade on TTCE not only identifies the likelihood of PAVMs but also predicts the probability for embolization.

Pulmonary arteriovenous malformations presenting with upper back pain in an adult: A case report and literature review

Pulmonary arteriovenous malformations (PAVMs) are the abnormal connections between the pulmonary artery and pulmonary veins branches without intervening in the pulmonary vascular bed. Although the most common cause of PAVMs is hereditary hemorrhagic telangiectasia, the etiology of single PAVMs appears to be idiopathic. Dyspnea, cyanosis, cerebrovascular events, and brain abscess are the common clinical manifestations of these lesions, though they may present with a nonspecific symptom as upper back pain. Computed tomography is the gold standard investigation for diagnosing pulmonary arteriovenous malformations, and demonstrating their size and extent before therapy. Transcatheter embolization is the first-choice treatment for patients without severe complications. Surgical intervention is reserved for the lesions not amenable to embolotherapy.

Haemoptysis: just another case of endocarditis? A case report

Background 

Pulmonary arteriovenous malformations (PAVM) are rare, and most cases are congenital. They require prompt recognition and management particularly in patients presenting with hypoxia and haemoptysis. We describe a unique case of recurrent endocarditis causing pulmonary artery aneurysms (PAAs) and formation of PAVM.

Case summary 

A 60-year-old woman presented with dyspnoea, haemoptysis, and severe hypoxia. Her background was significant for previous pacemaker lead infection, refractory heart failure secondary to severe tricuspid valve distortion by her pacemaker lead, tricuspid and mitral valve replacements complicated by recurrent endocarditis over several years. Two years prior to her current presentation computed tomography (CT) scanning revealed new small PAAs thought possibly to be mycotic in origin. After her current presentation, prompt high-resolution CT scanning of her chest with contrast revealed significant pulmonary haemorrhage and new clusters of PAVM. Urgent pulmonary angiography confirmed PAVM and was successfully treated with coil embolization. Her dyspnoea, pulmonary haemorrhage, and hypoxia resolved.

Discussion 

Acquired causes account for a very small percentage of PAVM and the mechanism of their development is unknown. As she had recurrent right-sided endocarditis and her PAAs developed following this, with new PAVM developing 2 years later; we hypothesize that they were causally related. We believe this is the first case of recurrent left- and right-sided endocarditis leading to formation of PAAs and development of PAVM presenting with significant hypoxia and haemoptysis requiring prompt intervention.

Diagnosis and endovascular management of pulmonary arteriovenous malformations

Pulmonary arteriovenous malformations (PAVM) are abnormal communication of a branch of the pulmonary artery and pulmonary vein circumventing the intervening pulmonary capillaries. This results in a right-to-left (R-L) shunt and its related manifestations, which include hampered gas exchange leading to hypoxaemia, dyspnoea, paradoxical emboli leading to stroke, cerebral abscess, myocardial infarction and pulmonary haemorrhage due to rupture of the PAVM. Endovascular transcatheter embolization of the feeding vessels with coils or occlusion devices is the current standard care of treatment and preferred treatment modality. The articles aim to provide insights into the current trends in diagnosis, the current recommendations, approach and management options for patients with PAVM.