Pulmonary hypertension exacerbated by hereditary hemorrhagic telangiectasia combined with pulmonary arteriovenous fistula and pregnancy status: A case report.

Background: Hereditary hemorrhagic telangiectasia (HHT) is an uncommon autosomal dominant condition. The combination of pregnancy and HHT can exacerbate pulmonary hypertension (PH) and, in severe cases, lead to fatality. Case presentation: The case we presented is a 28-year-old multiparous woman. She developed chest tightness and dyspnea in the second trimester of pregnancy, which was not taken seriously at that time, and the symptoms worsened postpartum. Echocardiography showed elevated pulmonary artery pressure (PAP) and the computerized tomographic pulmonary angiogram revealed a significant pulmonary arteriovenous malformation. The patient's condition continued to deteriorate despite treatment to reduce pulmonary hypertension. We reviewed and updated the history of omission, recurrent epistaxis during pregnancy, and similar symptoms running in her family. Combined with the whole exon genetic testing report revealing the ACVRL1 gene mutation at chr12:52308295, the diagnosis of HHT was established. Four months later, a transcatheter closure of the pulmonary arteriovenous fistula was performed, with satisfying outcomes presenting a decrease of more than 15 mmHg in the pulmonary artery pressure. As of right now, the patient's status is stable during the outpatient follow-up. Conclusions: HHT is a rare condition that typically occurs alongside abnormal communication between pulmonary veins and arteries, leading to a high-flow state in the pulmonary circulation. A pulmonary hypertension crisis can also be triggered by the patient's pregnancy, which further increases blood volume. By reducinhttps://www.ecdc.europa.eu/sites/default/files/documents/Methods-for-the%20detection-and-characterisation-of-SARS-CoV-2-variants-first-update-WHO-20-Dec-2021.pdfg pulmonary vascular flow, catheter closure of the pulmonary arteriovenous fistula decreases pulmonary arterial pressure.

Increased Risk for Infections and Allergic Disease in Hereditary Hemorrhagic Telangiectasia.

Background/Objectives: Hereditary hemorrhagic telangiectasia (HHT) is a rare disorder characterized by dilated blood vessels. Different immunological changes have been described in these patients. In this study, the predisposition of patients with HHT to infections and allergic diseases was assessed. Methods: Patients with HHT completed an online survey in English or German. Their data were compared to non-affected partners or friends. Results: A total of 430 out of 588 respondents with HHT answered our questions about infections and allergies. Patients with HHT suffered significantly more often from various types of allergies than their partners, especially type I allergies (n = 226/276, 82%), and had a higher risk for sinusitis, urinary tract infections, pulmonary infections, and abscesses. A total of 38% of the patients took antibiotics prior to dental or surgical procedures (n = 57/152), and, in 10% of these patients, pulmonary arteriovenous malformations (PAVMs) were not detected. On the other hand, 51% of patients with PAVM did not report a prophylactic antibiotic intake (n = 40/79). The patients who needed iron supplementations suffered more often from sepsis (OR: 9.00, 95%CI: 0.92-88.16). Conclusions: Compared to their non-affected controls, patients with HHT showed an increased risk for infections in different organs and allergic diseases. There is a need for campaigns raising greater awareness recommending prophylactic antibiotic intake in patients with PAVM.

Vascular Plugs Improve Pulmonary Arteriovenous Malformation Occlusion over Coil Embolization Alone: A Proof-of-Concept Study using Dual Energy Computed Tomography.

PURPOSE: To evaluate efficacy of pulmonary arteriovenous malformation (PAVM) embolization using dual-energy computed tomography (DECT) and spectral curve analysis by characterizing contrast enhancement and vascular perfusion as a surrogate of the degree of vascular occlusion after embolotherapy. METHODS: Nine consecutive adult patients underwent embolization for 21 PAVMs (size range 0.4-2.0cm; 15/21 simple angioarchitecture) and subsequent post-embolization chest DECT angiography. Twelve PAVMS were treated with vascular plugs ± coils, whereas nine PAVMs were treated with coils-only. Virtual spectral curves (VSC) were generated using dual-energy image post-processing in order to measure embolization effectiveness. RESULTS: Complete occlusion of target PAVM was achieved in all cases on digital subtraction angiography at the end of the embolization procedure. With a median follow-up of 12.7 months, the vascular plug group demonstrated significantly less vascular opacification compared to the coils-only group, as measured by opacification between upstream feeding artery and and different downstream vasculature locations (Δslope1: median 79.1 versus 28.6, p=0.0030; Δslope2: 76.4 versus 28.6, p=0.0197; Δslope3: 78.9 versus 28.6, p=0.0041). Persistence occurred in three PAVMs based on size criteria, which demonstrated higher vascular vascular opacification by DECT (Δslope1: 72 versus 28.6, p=0.253; Δslope2: 65.1 versus 32.7, p=0.326; Δslope3: 72.9 versus 53.5, p=0.733), although statistical significance was not reached. CONCLUSION: Similar to emerging literature, DECT showed improved occlusion in PAVMs treated with vascular plugs compared to coils alone.

ACR Appropriateness Criteria® Pulmonary Arteriovenous Malformation (PAVM): 2023 Update.

Pulmonary arteriovenous malformations (PAVMs) occur in 30% to 50% of patients with hereditary hemorrhagic telangiectasia. Clinical presentations vary from asymptomatic disease to complications resulting from the right to left shunting of blood through the PAVM such as paradoxical stroke, brain abscesses, hypoxemia, and cardiac failure. Radiology plays an important role both in the diagnosis and treatment of PAVM. Based on different clinical scenarios, the appropriate imaging study has been reviewed and is presented in this document. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Selective Angiographic Evaluation in Patients with Simple-Type Pulmonary Arteriovenous Malformations Treated with Vascular Plug.

PURPOSE: To evaluate the angiographic recanalization rate of patients who underwent embolization juxta-proximal to the sac with AMPLATZER Vascular Plug type IV (AVP IV) for a simple pulmonary arteriovenous malformation (PAVM). MATERIAL AND METHODS: Ten patients (7 females and 3 males; median age, 47 years [range 28-83 years]) with 19 simple-type PAVMs who underwent embolization using an AVP IV between May 2015 and November 2021 were included in this retrospective study. The median feeding artery diameter on computed tomography was 4.0 mm (range 3-5.9 mm), and the median ratio of AVP IV size to feeding artery diameter on computed tomography was 1.5 (range 1.3-2.1). Technical success was defined by AVP IV placement at the junction between the pulmonary artery and the sac, or the pulmonary artery within 1 cm from the junction and beyond the last normal branch. The primary endpoint was the PAVM recanalization rate in selective or segmental pulmonary angiography performed 1 year post-embolization. RESULTS: The technical success rate of embolization juxta-proximal to the sac for simple-type PAVMs was 100%. None of the 19 lesions showed recanalization in pulmonary angiography performed 1 year after embolization. One patient experienced hemoptysis and pneumonia. CONCLUSION: Embolization of simple-type PAVMs' feeding vessel using AVP IV is safe and effective, with a high technical success rate and no recanalization on pulmonary angiography performed at 1 year post-embolization.

Unveiling the complexity: coexistence of rheumatic heart disease and pulmonary arteriovenous malformation-a unique case report.

Background: The coexistence of rheumatic heart disease (RHD) and pulmonary arteriovenous malformation (PAVM) is a rare clinical scenario that poses diagnostic and therapeutic challenges. This case report explores the clinical presentation, diagnostic journey, and multidisciplinary management of a patient presenting with both conditions. Case summary: A 47-year-old female with a history of RHD presented with symptoms of dyspnoea on exertion and cyanosis, suggestive of both cardiac involvement and pulmonary involvement. Subsequent investigations involving imaging, echocardiography, and invasive pulmonary angiography revealed the coexistence of RHD and multiple PAVM in the patient's left lower lobe of the lung. The patient underwent a tailored treatment plan, initially involving percutaneous mitral balloon valvuloplasty for RHD, followed by a staged procedure of transcatheter PAVM closure with Amplatzer™ Vascular Plug II performed 1 month later. Her saturation normalized following the intervention. The patient's progress was monitored closely, with adjustments made to the treatment plan based on evolving clinical scenarios. The patient remained well in short-term follow-up. Discussion: This case highlights the complexity of managing patients having two diverse conditions RHD and PAVM coexisting together, thus emphasizing the importance of a multidisciplinary approach. The unique intersection of cardiac and pulmonary pathologies necessitates careful consideration of diagnostic nuances and tailored treatment strategies. Lessons learned from this case offer valuable insights for clinicians encountering similar scenarios and underscore the significance of individualized, patient-centred care in optimizing outcomes for those with dual pathologies.

Angiographic tool to detect pulmonary arteriovenous malformations in single ventricle physiology.

OBJECTIVE: Individuals with single ventricle physiology who are palliated with superior cavopulmonary anastomosis (Glenn surgery) may develop pulmonary arteriovenous malformations. The traditional tools for pulmonary arteriovenous malformation diagnosis are often of limited diagnostic utility in this patient population. We sought to measure the pulmonary capillary transit time to determine its value as a tool to identify pulmonary arteriovenous malformations in patients with single ventricle physiology. METHODS: We defined the angiographic pulmonary capillary transit time as the number of cardiac cycles required for transit of contrast from the distal pulmonary arteries to the pulmonary veins. Patients were retrospectively recruited from a single quaternary North American paediatric centre, and angiographic and clinical data were reviewed. Pulmonary capillary transit time was calculated in 20 control patients and compared to 20 single ventricle patients at the pre-Glenn, Glenn, and Fontan surgical stages (which were compared with a linear-mixed model). Correlation (Pearson) between pulmonary capillary transit time and haemodynamic and injection parameters was assessed using angiograms from 84 Glenn patients. Five independent observers calculated pulmonary capillary transit time to measure reproducibility (intraclass correlation coefficient). RESULTS: Mean pulmonary capillary transit time was 3.3 cardiac cycles in the control population, and 3.5, 2.4, and 3.5 in the pre-Glenn, Glenn, and Fontan stages, respectively. Pulmonary capillary transit time in the Glenn population did not correlate with injection conditions. Intraclass correlation coefficient was 0.87. CONCLUSIONS: Pulmonary angiography can be used to calculate the pulmonary capillary transit time, which is reproducible between observers. Pulmonary capillary transit time accelerates in the Glenn stage, correlating with absence of direct hepatopulmonary venous flow.

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.

Successful embolization of a clinically significant pulmonary arteriovenous malformation.

The authors present the clinical case of a 59-year-old female patient with a history of peripheral desaturation, which was detected in the perioperative period 4 years earlier. She reported exertional dyspnea, quantified as grade 2 on the Modified Medical Research Council (mMRC) Dyspnea Scale (walks slower than people of the same age because of dyspnea or has to stop for breath when walking at her own pace), and morning cough with mucoid sputum and denied platypnea, epistaxis, telangiectasias and hemoptysis. A computed chest tomography scan revealed a contrast-enhanced lesion on the right upper lobe with an afferent and two efferent vessels compatible with pulmonary arteriovenous malformation. The transesophageal echocardiogram revealed an important right-left shunt compatible with arteriovenous fistula in the pulmonary circulation. An angiography confirmed the diagnosis and a selective embolization of the afferent artery was performed with resolution of symptoms.

[Ischemic stroke due to paradoxical embolism through pulmonary arteriovenous malformation in a young patient]. / ACV isquémico debido a embolia paradojal a través de malformación arteriovenosa pulmonar en paciente joven.

Paradoxical embolism due to an isolated pulmonary arteriovenous malformation (PAVM) is a rare cause of ischemic stroke. PAVMs are abnormal high-flow connections between pulmonary arteries and veins, diverting deoxygenated blood into the systemic circulation and they represent a less common source of paradoxical embolisms, especially in young individuals. Endovascular embolization is the preferred treatment for clinically significant PAVMs. We present the case of a 34-year-old woman with a left thalamic ischemic stroke. Severe contrast passage was detected in cerebral arteries through transcranial Doppler. Intracardiac ultrasound did not reveal a patent foramen ovale, prompting further investigation with pulmonary CT angiography, confirming the presence of PAVM. The patient underwent successful endovascular treatment. It is essential to consider PAVM in the etiological diagnosis of ischemic stroke, especially in young patients with signs of abnormal right-to-left communication. Periodic follow-up imaging is recommended to assess potential recurrence or changes in PAVM, emphasizing the importance of appropriate management of these malformations.

La embolia paradojal debido a una malformación arteriovenosa pulmonar (MAVP) aislada es una causa infrecuente de accidente cerebrovascular (ACV) isquémico. Las MAVP son conductos anómalos de alta circulación entre arterias y venas pulmonares, desviando sangre desoxigenada hacia la circulación sistémica y representan una fuente menos común de embolias paradojales, especialmente en personas jóvenes. La embolización endovascular es el tratamiento preferido para MAVP clínicamente significativas. Presentamos el caso de una mujer de 34 años con ACV isquémico talámico izquierdo. Se detectó pasaje de burbujas "en cortina" en arterias cerebrales mediante Doppler transcraneal. En ecografía intracardíaca no se encontró foramen oval permeable, motivo por el cual se avanzó con realización de angiotomografía pulmonar, la cual confirmó la presencia de MAVP. La paciente recibió tratamiento endovascular exitoso. Es esencial considerar la MAVP en el diagnóstico etiológico del ACV isquémico, especialmente en pacientes jóvenes con signos de comunicación anormal de derecha a izquierda. Se recomienda un seguimiento periódico mediante imágenes para evaluar la posible recurrencia o cambios en la MAVP, resaltando la importancia del manejo adecuado de estas malformaciones.

Life-threatening hemothorax due to rupture of pulmonary arteriovenous malformation during pregnancy.

Pulmonary arteriovenous malformation (PAVM) can worsen in pregnant women due to pregnancy-related physiological changes. If a PAVM ruptures, it can become life-threatening. A 24-year-old female patient at 22 weeks of gestation presented to the hospital with chest pain and dyspnea. A simple chest radiograph revealed that the right lung was almost completely collapsed due to massive pleural effusion, and the heart was displaced to the opposite side. Closed thoracostomy was performed and 2 l of blood was drained. Chest CT revealed the presence of a PAVM in the right upper lung. Emergency surgery was performed to resect the PAVM through thoracoscopic pulmonary wedge resection. The patient experienced disseminated intravascular coagulation and acute renal insufficiency after the surgery, but eventually recovered and was discharged without any complications on the sixth postoperative day.

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.

Angiographic Tool to Detect Pulmonary Arteriovenous Malformations in Single Ventricle Physiology.

Background: Individuals with single ventricle physiology who are palliated with superior cavopulmonary anastomosis (Glenn surgery) may develop pulmonary arteriovenous malformations (PAVMs). The traditional tools for PAVM diagnosis are often of limited diagnostic utility in this patient population. We sought to measure the pulmonary capillary transit time (PCTT) to determine its value as a tool to identify PAVMs in patients with single ventricle physiology. Methods: We defined the angiographic PCTT as the number of cardiac cycles required for transit of contrast from the distal pulmonary arteries to the pulmonary veins. Patients were retrospectively recruited from a single quaternary North American pediatric center, and angiographic and clinical data was reviewed. PCTT was calculated in 20 control patients and compared to 20 single ventricle patients at the pre-Glenn, Glenn, and Fontan surgical stages (which were compared with a linear-mixed model). Correlation (Pearson) between PCTT and hemodynamic and injection parameters was assessed using 84 Glenn angiograms. Five independent observers calculated PCTT to measure reproducibility (intra-class correlation coefficient). Results: Mean PCTT was 3.3 cardiac cycles in the control population, and 3.5, 2.4, and 3.5 in the pre-Glenn, Glenn, and Fontan stages, respectively. PCTT in the Glenn population did not correlate with injection conditions. Intraclass correlation coefficient was 0.87. Conclusions: Pulmonary angiography can be used to calculate the pulmonary capillary transit time, which is reproducible between observers. PCTT accelerates in the Glenn stage, correlating with absence of direct hepatopulmonary venous flow.

Use of Polyurethane-Covered Stents for Exclusion of Pulmonary Arteriovenous Malformations.

PURPOSE: To evaluate the safety, technical success and short-term effectiveness of polyurethane-covered stent (PK Papyrus, BioTronik, Berlin) in the treatment of pulmonary arteriovenous malformations (PAVMs) that are not amenable to embolotherapy. MATERIALS AND METHODS: In this IRB-approved, retrospective study, data from patients who received polyurethane-covered stents for exclusion of PAVMs were analyzed. The study included 5 patients (all women) with a median age of 40 years (range 25-60). Patients presented with hypoxemia, TIAs, and/or epistaxis; 4 were confirmed to have HHT. All had multiple PAVMs diagnosed on chest CT and underwent embolization with other devices in addition to the polyurethane-covered stent. The indication for stent placement in all cases was a short and/or tortuous feeding artery. Safety was assessed by immediate or short-term complications, e.g., migration, stent thrombosis, and fracture. Technical success was defined as the ability to accurately place the stent at the intended location. Effectiveness was defined as successful exclusion of PAVM with no perfusion across the AVM. RESULTS: Technical success of stent placement was 100%. AVM exclusion rate was 80% after single stent deployment; in the case of incomplete exclusion, success was achieved using an overlapping stent to completely cover a second feeding artery. During the median follow-up period of 5 months (range 2-10), all stents remained patent, and AVMs were excluded without other complications. CONCLUSION: Exclusion of PAVMs with polyurethane-covered stents is technically feasible, safe, and shows short-term effectiveness for PAVMs with a short/tortuous feeding artery when traditional embolization techniques are not possible.

Pulmonary arteriovenous malformations in patients with previous brain abscess: a cross-sectional population-based study.

BACKGROUND AND PURPOSE: Pulmonary arteriovenous malformations (PAVMs) may cause recurrent brain abscess. The primary aim was to determine the prevalence of PAVM amongst survivors of brain abscess. The proportion with cardiac right-to-left shunts was also assessed post hoc. METHODS: This was a cross-sectional population-based study of adult (≥18 years) survivors of cryptogenic bacterial brain abscess in Denmark from 2007 through 2016. Patients were invited for bubble-echocardiography to detect vascular right-to-left shunting and, if abnormal, subsequent computed tomography thorax for diagnosis of PAVM. Data are presented as n/N (%) or median with interquartile range (IQR). RESULTS: Study participation was accepted by 47/157 (30%) eligible patients amongst whom two did not appear for scheduled bubble-echocardiography. The median age of participants was 54 years (IQR 45-62) and 19/57 (33%) were females compared with 59 years (IQR 48-68, p = 0.05) and 41/85 females (48%, p = 0.22) in non-participants. Bubble-echocardiography was suggestive of shunt in 10/45 (22%) participants and PAVM was subsequently confirmed by computed tomography in one patient with grade 1 shunting. The corresponding prevalence of PAVM was 2% (95% confidence interval 0.06-11.8) amongst all examined participants. Another 9/45 (20%) were diagnosed with patent in persistent foramen ovale (n = 8) or atrial septum defect (n = 1), which is comparable with the overall prevalence of 25% amongst adults in the Danish background population. CONCLUSIONS: Undiagnosed PAVM amongst adult survivors of cryptogenic bacterial brain abscess is rare but may be considered in select patients. The prevalence of cardiac right-to-left shunts amongst brain abscess patients corresponds to the prevalence in the general population.

A Congenital Portosystemic Shunt in a Child With Heterotaxy, Situs Inversus, Polysplenia, and Interrupted Inferior Vena Cava With Azygous Continuation.

Congenital portosystemic shunts are rare vascular malformations in which portal venous blood from the intestines and spleen bypasses the liver and diverts directly into the systemic circulation through abnormal vessels. We report a case of a 4-year-old girl with heterotaxy syndrome, polysplenia, and situs inversus presenting with persistent hypoxemia who was found to have pulmonary arteriovenous malformations (PAVMs) and hypoxemia secondary to a congenital portosystemic shunt. Management of this patient's PAVMs involved endovascular occlusion of the portosystemic shunt with subsequent resolution of hypoxemia. PAVMs secondary to extrahepatic portosystemic shunt should be explored as a cause of progressive cyanosis in children with heterotaxy, polysplenia, and interrupted inferior vena cava with azygous continuation.

Case report: video-assisted thoracoscopic surgery for pulmonary arteriovenous malformation using near-infrared fluorescence with indocyanine green.

BACKGROUND: Pulmonary arteriovenous malformation (PAVM) is an abnormal communication between pulmonary vasculatures and has an unclear boundary with surrounding lung tissues. At present, surgeons can only determine its location by preoperative imaging and intraoperative palpation, despite its soft texture. Indocyanine green(ICG), a near-infrared fluorophore, has been demonstrated useful in the accurate identification of vascular tissue. Therefore, we explored its application in PAVM cases. CASE PRESENTATION: We present two PAVM cases using near-infrared fluorescence (NIF) with 25 mg ICG at 5 mg/ml to achieve intraoperative visualization of the lesion in video-assisted thoracoscopic surgery (VATS). Under the NIF mode, ICG systemic injection led to successive signaling of the anomaly and normal tissues in merely 10 s, which helped us distinguish them efficiently and precisely. A peak signal-to-background ratio of 2.2 confirmed the significant fluorescence difference and excluded interference from carbon dust. CONCLUSIONS: We are the first to report the use of such an approach in delineating the margin of vascular malformation with high contrast, and this new finding may help minimize the damage to lung function in PAVM treatment. Further exploration and validation are needed to determine its role.

Pregnancy and delivery after percutaneous embolization with a combination of microvascular plugs and hydrogel-coated coils for unilateral diffuse pulmonary arteriovenous malformations: a case report.

Background: Pulmonary arteriovenous malformations (PAVMs) are abnormal communications between the pulmonary arteries and veins; right-to-left shunts can cause hypoxaemia, emboli to systemic circulation, and brain abscesses. Cyanosis during pregnancy may increase the probability of premature birth or spontaneous abortion and may increase maternal cardiac complications. Case summary: We describe a case of a 24-year-old woman with diffuse multiple PAVMs localized to the left inferior lobe and chronic cyanosis. She had increased exertional fatigue and chronic headaches and was New York Heart Association class II, although her rest sitting peripheral oxygen saturation (SpO2) had remained unchanged at 83% over the past 20 years. She underwent percutaneous embolization with microvascular plugs and hydrogel-coated coils. A microvascular plug was placed as an anchor near the venous sac, followed by hydrogel-coated coil embolization of the proximal pulmonary artery. A total of six sessions of catheter intervention were performed. The embolization was successful, her hypoxaemia was relieved, and she was able to conceive and deliver. Three years have passed since the last session, and SpO2 97% has been maintained. Discussion: In the treatment of complex PAVMs, the combination of microvascular plugs and hydrogel-coated coils resulted in shorter procedure time, lower risk of migration of the embolus to the pulmonary veins, and less recanalization and revascularization. Percutaneous embolization of PAVMs resulted in safe delivery for the mother and child.