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Background: Pediatric pulmonary vein stenosis (PVS) is often progressive and treatment-refractory, requiring multiple interventions. Hybrid pulmonary vein interventions (HPVIs), involving intraoperative balloon angioplasty or stent placement, leverage surgical access and customization to optimize patency while facilitating future transcatheter procedures. We review our experience with HPVI and explore potential applications of this collaborative approach. Methods: Retrospective chart review of all HPVI cases between 2009 to 2023. Results: Ten patients with primary (n = 5) or post-repair (n = 5) PVS underwent HPVI at median age of 12.7 months (range 6.6 months-9.5 years). Concurrent surgical PVS repair was performed in 7/10 cases. Hybrid pulmonary vein intervention was performed on 17 veins, 13 (76%) with prior surgical or transcatheter intervention(s). One patient underwent intraoperative balloon angioplasty of an existing stent. In total, 18 stents (9 bare metal [5-10 mm diameter], 9 drug eluting [3.5-5 mm diameter]) were placed in 16 veins. At first angiography (median 48 days [range 7 days-2.8 years] postoperatively), 8 of 16 (50%) HPVI-stented veins developed in-stent stenosis. Two patients died from progressive PVS early in the study, one prior to planned reintervention. Median time to first pulmonary vein reintervention was 86 days (10 days-2.8 years; 8/10 patients, 13/17 veins). At median survivor follow-up of 2.2 years (2.3 months-13.1 years), 1 of 11 surviving HPVI veins were completely occluded. Conclusions: Hybrid pulmonary vein intervention represents a viable adjunct to existing PVS therapies, with promising flexibility to address limitations of surgical and transcatheter modalities. Reintervention is anticipated, necessitating evaluation of long-term benefits and durability as utilization increases.
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The removal of balloon fragments from the pulmonary artery without damaging the pulmonary and tricuspid valves can be difficult. Four cases during transcatheter pulmonary valve replacement are described in which a novel retrieval system was used to facilitate safe removal. (Level of Difficulty: Advanced.).
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BACKGROUND: The data on the use of Gore Cardioform Septal Occluder (GCA; W. L. Gore and Associates, Inc.) for atrial septal defect (ASD) with deficient rims is limited. METHODS: All patients evaluated by transesophageal echocardiogram (TEE) for ASD occlusion were included. TEE planes at 35°, 0°, and 90° were assessed for anterior-superior (AS) and posterior (P), anterior-inferior (AI) and posterior-superior (PS), as well as superior (S) and inferior (I) rims. ASD size >20 mm, and rims less than 5 mm were defined as large and deficient, respectively. We included patients who had a procedural failure along with the patients in whom the procedure was not attempted after echocardiogram in the unsuccessful group. RESULTS: In 148 patients, the median weight, age, and ASD size were 36 kg (range, 8-60 kg), 11.8 years (range, 1-60 years), and 14.2 ± 8.28 mm, respectively. One or more deficient rims were noted in 112 of 148 (75.7%): 99 (67%) AS, 36 (24%) P, 17 (11%) AI, 30 (20%) PS, 26 (18%) S, and 33 (22%) I. ASD closure was performed in 115 (78%) patients. The procedure was successful in 111 (96.5%) patients with procedural failure in 4 (3.4%) patients. Multiple deficient rims were associated with reduced procedural success (OR 0.36, 95% CI, 0.25-0.56). On multivariate analysis deficient P, PS, and I rims were associated with an unsuccessful group (P = .001, .046, and .005, respectively). Complications included 1 device embolization, 1 vascular injury, and 5 arrhythmias. CONCLUSIONS: Transcatheter closure of ASDs with deficient rims is feasible using GCA. Large ASDs with deficient P, PS, and I rims were associated with unsuccessful closure. Risk stratification and comprehensive evaluation of ASD rims is vital for the use of GCA.
Subject(s)
Heart Septal Defects, Atrial , Septal Occluder Device , Humans , Cardiac Catheterization , Heart Septal Defects, Atrial/diagnosis , Heart Septal Defects, Atrial/surgery , Echocardiography, Transesophageal , Echocardiography , Arrhythmias, Cardiac , Treatment OutcomeSubject(s)
Extracorporeal Membrane Oxygenation , Humans , Infant , Thrombectomy , Ischemia , Lower Extremity , Catheters , Retrospective StudiesABSTRACT
Single ventricle patients eligible for Fontan completion undergo pre-Fontan catheterization for hemodynamic and anatomic assessment prior to surgery. Cardiac magnetic resonance imaging may be used to evaluate pre-Fontan anatomy, physiology, and collateral burden. We describe our center's outcomes in patients undergoing pre-Fontan catheterization combined with cardiac magnetic resonance imaging. A retrospective review of patients undergoing pre-Fontan catheterization from 10/2018 to 04/2022 at Texas Children's Hospital was performed. Patients were divided into 2 groups: combined cardiac magnetic resonance imaging and catheterization (combined group) and those who underwent catheterization only (catheterization only group). There were 37 patients in the combined group and 40 in the catheterization only group. Both groups were similar in age and weight. Patients undergoing combined procedures received less contrast, and experienced less in-lab time, fluoroscopy time and catheterization procedure time. Median radiation exposure was lower in the combined procedure group but was not statistically significant. Intubation and total anesthesia times were higher in the combined procedure group. Patients undergoing a combined procedure were less likely to have collateral occlusion performed than in the catheterization only group. Bypass time, intensive care unit length of stay, and chest tube duration were similar in both groups at the time of Fontan completion. Combined pre-Fontan assessment decreases catheterization procedure and fluoroscopy time associated with cardiac catheterization at the expense of longer anesthetic times, and results in similar Fontan outcomes compared to when cardiac catheterization alone is utilized.
Subject(s)
Heart Septal Defects, Atrial , Humans , Treatment Outcome , Echocardiography , Cardiac CatheterizationABSTRACT
BACKGROUND: Fontan baffle punctures and creation of Fontan fenestration for cardiac catheterisation procedures remain challenging especially due to the heavy calcification of prosthetic material and complex anatomy. OBJECTIVES: We sought to evaluate our experience using radiofrequency current via surgical electrocautery needle for Fontan baffle puncture to facilitate diagnostic, electrophysiology, and interventional procedures. METHODS: A retrospective chart review of all Fontan patients (pts) who underwent Fontan baffle puncture using radiofrequency energy via surgical electrocautery from three centres were performed from January 2011 to July 2021. RESULTS: A total of 19 pts underwent 22 successful Fontan baffle puncture. The median age and weight were 17 (3-36 years) and 55 (14-88) kg, respectively. The procedural indications for Fontan fenestration creation included: diagnostic study (n = 1), atrial septostomy and stenting (n = 1), electrophysiology study and ablation procedures (n = 8), Fontan baffle stenting for Fontan failure including protein-losing enteropathy (n = 7), and occlusion of veno-venous collaterals (n = 2) for cyanosis. The type of Fontan baffles included: extra-cardiac conduits (n = 12), lateral tunnel (n = 5), classic atrio-pulmonary connection (n = 1), and intra-cardiac baffle (n = 1). A Fontan baffle puncture was initially attempted using traditional method in 6 pts and Baylis radiofrequency trans-septal system in 2 pts unsuccessfully. In all pts, Fontan baffle puncture using radiofrequency energy via electrocautery needle was successful. The radiofrequency energy utilised was (10-50 W) and required 1-5 attempts for 2-5 seconds. There were no vascular or neurological complications. CONCLUSIONS: Radiofrequency current delivery using surgical electrocautery facilitates Fontan baffle puncture in patients with complex and calcified Fontan baffles for diagnostic, interventional, and electrophysiology procedures.
Subject(s)
Fontan Procedure , Heart Defects, Congenital , Humans , Heart Defects, Congenital/complications , Retrospective Studies , Heart , Cardiac Catheterization , Electrocoagulation , Treatment OutcomeABSTRACT
BACKGROUND: Anomalous aortic origin of the left coronary artery with intraseptal course is a rare coronary anomaly associated with an increased risk of myocardial ischaemia. The role and techniques for surgical intervention are evolving, with numerous novel surgical techniques for this challenging anatomy reported in the last 5 years. We report our single-centre experience with surgical repair of intraseptal anomalous left coronary artery in the paediatric population, including clinical presentation, evaluation, and short- to mid-term outcomes. METHODS: All patients with coronary anomalies presenting to our institution undergo standardised clinical evaluation. Five patients aged 4 to 17 years underwent surgical intervention for intraseptal anomalous aortic origin of the left coronary artery between 2012 and 2022. Surgical techniques included coronary artery bypass grafting (n = 1), direct reimplantation with limited supra-arterial myotomy via right ventriculotomy (n = 1), and transconal supra-arterial myotomy with right ventricular outflow tract patch reconstruction (n = 3). RESULTS: All patients had evidence of haemodynamically significant coronary compression, and three had evidence of inducible myocardial ischaemia pre-operatively. There were no deaths or major complications. Median follow-up was 6.1 months (range 3.1-33.4 months). Patients who underwent supra-arterial myotomy (with or without reimplantation) had improved coronary flow and perfusion based on stress imaging and catheterisation data. CONCLUSIONS: Surgical approaches to intraseptal anomalous left coronary artery with evidence of myocardial ischaemia continue to evolve, with new techniques demonstrating promising improvement in coronary perfusion. Further studies are warranted to determine long-term outcomes and refine indications for repair.
Subject(s)
Anomalous Left Coronary Artery , Coronary Artery Disease , Coronary Vessel Anomalies , Myocardial Ischemia , Child , Humans , Anomalous Left Coronary Artery/complications , Coronary Vessel Anomalies/diagnosis , Coronary Vessel Anomalies/surgery , Coronary Vessel Anomalies/complications , Myocardial Ischemia/complications , Myocardial Ischemia/surgery , Coronary Artery Disease/complications , Aorta/abnormalities , Coronary Vessels/diagnostic imaging , Coronary Vessels/surgery , Retrospective Studies , Treatment OutcomeABSTRACT
Coronavirus disease 2019 (COVID-19) infection in children has been associated with thrombosis, though few cases of COVID-associated pulmonary embolism (PE) have been described. We performed a retrospective review of the nine cases of COVID-19-associated PE during the B.1617.2 variant surge at Texas Children's Hospital. The patient cohort largely contained unvaccinated obese adolescents. All patients were critically ill with two requiring catheter-directed thrombolysis in addition to anticoagulation. Eight of the nine patients had COVID pneumonia along with PE. This report stresses the importance of maintaining a high index of suspicion for PE in pediatric COVID-19 infection and vaccinating obese adolescent patients.
Subject(s)
COVID-19 , Pediatric Obesity , Pulmonary Embolism , Thrombosis , Adolescent , COVID-19/complications , Child , Humans , Pulmonary Embolism/etiology , SARS-CoV-2 , Thrombosis/drug therapy , Thrombosis/etiologyABSTRACT
BACKGROUND: Coronary artery fistulas (CAFs) presenting in infancy are rare, and data regarding postclosure sequelae and follow-up are limited. METHODS: A retrospective review of all the neonates and infants (<1 year) was conducted from the CAF registry for CAF treatment. The CAF type (proximal or distal), size, treatment method, and follow-up angiography were reviewed to assess outcomes and coronary remodeling. RESULTS: Forty-eight patients were included from 20 centers. Of these, 30 were proximal and 18 had distal CAF; 39 were large, 7 medium, and 2 had small CAF. The median age and weight was 0.16 years (0.01-1) and 4.2 kg (1.7-10.6). Heart failure was noted in 28 of 48 (58%) patients. Transcatheter closure was performed in 24, surgical closure in 18, and 6 were observed medically. Procedural success was 92% and 94 % for transcatheter closure and surgical closure, respectively. Follow-up data were obtained in 34 of 48 (70%) at a median of 2.9 (0.1-18) years. Angiography to assess remodeling was available in 20 of 48 (41%). I. Optimal remodeling (n=10, 7 proximal and 3 distal CAF). II. Suboptimal remodeling (n=7) included (A) symptomatic coronary thrombosis (n=2, distal CAF), (B) asymptomatic coronary thrombosis (n=3, 1 proximal and 2 distal CAF), and (C) partial thrombosis with residual cul-de-sac (n=1, proximal CAF) and vessel irregularity with stenosis (n=1, distal CAF). Finally, (III) persistent coronary artery dilation (n=4). Antiplatelets and anticoagulation were used in 31 and 7 patients post-closure, respectively. Overall, 7 of 10 (70%) with proximal CAF had optimal remodeling, but 5 of 11 (45%) with distal CAF had suboptimal remodeling. Only 1 of 7 patients with suboptimal remodeling were on anticoagulation. CONCLUSIONS: Neonates/infants with hemodynamically significant CAF can be treated by transcatheter or surgical closure with excellent procedural success. Patients with distal CAF are at higher risk for suboptimal remodeling. Postclosure anticoagulation and follow-up coronary anatomic evaluation are warranted.
Subject(s)
Coronary Vessel Anomalies , Vascular Fistula , Coronary Angiography , Coronary Vessel Anomalies/diagnostic imaging , Coronary Vessel Anomalies/therapy , Follow-Up Studies , Humans , Infant , Infant, Newborn , Registries , Retrospective Studies , Treatment OutcomeABSTRACT
OBJECTIVES: To describe a deployment technique of the Gore Cardioform atrial septal defect (ASD) occluder (W.L. Gore and Associates) for large secundum ASDs and ASDs with challenging anatomy. BACKGROUND: The Gore Cardioform ASD occluder has recently been approved for closure of secundum ASDs; however, there are limitations to its delivery system. METHODS: A retrospective study was conducted on the use of a Mullins sheath (Cook Medical) to facilitate Gore Cardioform ASD occluder delivery for secundum ASD closure in the cardiac catheterization laboratory from June, 2017 to December, 2019 at Texas Children's Hospital/Baylor College of Medicine. RESULTS: Out of 98 patients who underwent an attempt at ASD closure using the Gore Cardioform ASD occluder, a Mullins sheath was used in 52 patients (median age, 8 years [interquartile range, 4-13 years] and weight 27.2 kg [interquartile range, 17.9-51.2 kg]), with a successful implant in 46/52 patients (88%). The Mullins sheath was primarily used to deliver large devices (>32 mm) in 38/46 successful implants (83%). There were 2 major adverse events (atrial fibrillation requiring cardioversion). At a median follow-up of 43 days (interquartile range, 1-374 days), no patient had more than a mild residual shunt. The ASD size, maximum sheath size, and device size were larger in patients in whom the Mullins sheath was used as compared with those patients in whom a Mullins sheath was not used. CONCLUSIONS: The Mullins sheath-facilitated delivery of the Gore Cardioform ASD occluder device may be a useful adjunct technique for closure of large secundum ASDs and secundum ASDs with challenging anatomy.
Subject(s)
Atrial Fibrillation , Heart Septal Defects, Atrial , Septal Occluder Device , Cardiac Catheterization , Child , Heart Septal Defects, Atrial/diagnosis , Heart Septal Defects, Atrial/surgery , Humans , Prosthesis Design , Retrospective Studies , Time Factors , Treatment OutcomeSubject(s)
Coronary Thrombosis , Fistula , Myocardial Infarction , Child , Coronary Angiography , Coronary Vessel Anomalies , Coronary Vessels , Humans , Treatment OutcomeABSTRACT
BACKGROUND: Tricuspid valve injury can occur during implantation of a SAPIEN valve in the pulmonary position. We describe our experience using a long Gore DrySeal (GDS) sheath to protect the tricuspid valve during advancement of the Commander delivery system. METHODS: Retrospective single center review of all patients who underwent placement of a SAPIEN valve in the right ventricular outflow tract between January 2016 and April 2020. Patients were divided into two groups: delivery of the valve using standard technique (Group I), and with the use of a GDS (Group II), for comparison. RESULTS: There were 48 patients in total: 25 in Group I and 23 in Group II. In Group II, the first 10 patients had a 29 mm S3 placed through a 26 French (Fr), 65 cm GDS. We then performed additional crimping of the S3 onto the balloon after the balloon catheter was withdrawn to position the valve on the balloon outside the body. Subsequently, seven had a 29 mm S3 placed through a 24 Fr GDS, and four had a 26 mm S3 placed through a 22 Fr GDS including one weighing 16 kg. Two had a 23 mm S3 placed through a 22Fr GDS as the 20Fr GDS was not available in our lab. Severe tricuspid valve injury occurred in 2/25 (8%) of Group I patients and 0/23 of Group II patients. CONCLUSION: Use of a long GDS may protect the tricuspid valve from injury during implantation of the S3 valve in the pulmonary position, and is technically feasible in smaller patients.
Subject(s)
Cardiac Catheterization/instrumentation , Heart Injuries/prevention & control , Heart Valve Prosthesis Implantation/instrumentation , Heart Valve Prosthesis , Hemodynamics , Pulmonary Valve/surgery , Tricuspid Valve Insufficiency/prevention & control , Tricuspid Valve/physiopathology , Adolescent , Adult , Balloon Valvuloplasty , Cardiac Catheterization/adverse effects , Child , Female , Heart Injuries/diagnostic imaging , Heart Injuries/etiology , Heart Injuries/physiopathology , Heart Valve Prosthesis Implantation/adverse effects , Humans , Male , Prosthesis Design , Pulmonary Valve/diagnostic imaging , Pulmonary Valve/physiopathology , Retrospective Studies , Risk Assessment , Risk Factors , Time Factors , Treatment Outcome , Tricuspid Valve/diagnostic imaging , Tricuspid Valve/injuries , Tricuspid Valve Insufficiency/diagnostic imaging , Tricuspid Valve Insufficiency/etiology , Tricuspid Valve Insufficiency/physiopathology , Young AdultABSTRACT
There have been no clinical studies evaluating the use of drug-eluting stents (DES) versus bare metal stents (BMS) for infants who underwent ductus arteriosus (DA) stent placement for ductal-dependent pulmonary blood flow (PBF). We aimed to compare the use of second-generation (fluoropolymer-coated everolimus) DES to BMS in infants who underwent DA stenting for ductal-dependent PBF. A retrospective study of infants who underwent DA stenting for ductal-dependent PBF from January 2004 to March 2018 at a single tertiary care pediatric hospital was performed. Of 94 infants identified, 71 (46 BMS and 25 DES) met inclusion criteria. Baseline characteristics of the DES and BMS cohorts were comparable. The patent lumen to stent diameter on subsequent angiographic evaluation was 81% in DES as compared with 50% in BMS group; pâ¯=â¯0.01. There were 2 deaths early in our experience, both in the BMS group. Unplanned reinterventions were less in the DES group (3, 12% patients) compared with the BMS group (13, 28%), pâ¯=â¯0.03. Pulmonary artery size as assessed using Nakata and pulmonary artery symmetry index was comparable in both the groups. There was no difference in infection rates between the groups. On multivariate analysis, prematurity, BMS, and lower oxygen saturations at discharge were associated with subsequent unplanned reintervention (pâ¯=â¯0.01, 0.03 and 0.03, respectively). In conclusion, our clinical experience suggests that in infants who underwent DA stenting for ductal-dependent PBF, (fluoropolymer-coated everolimus eluting) DES results in less luminal loss and lower unplanned reintervention for cyanosis as compared with BMS implantation.
Subject(s)
Blood Flow Velocity/physiology , Cardiac Surgical Procedures/methods , Drug-Eluting Stents , Ductus Arteriosus, Patent/surgery , Ductus Arteriosus/surgery , Everolimus/pharmacology , Pulmonary Artery/physiopathology , Angiography , Coated Materials, Biocompatible , Ductus Arteriosus/diagnostic imaging , Ductus Arteriosus, Patent/diagnosis , Ductus Arteriosus, Patent/physiopathology , Female , Follow-Up Studies , Humans , Immunosuppressive Agents/pharmacology , Infant, Newborn , Male , Pulmonary Artery/diagnostic imaging , Pulmonary Circulation/physiology , Retrospective Studies , Treatment OutcomeABSTRACT
In the era of neoadjuvant and adjuvant chemotherapy, extrapulmonary involvement by high-grade osteosarcoma (HGOS) is rare. Importantly however, HGOS metastasis in the form of cardiovascular tumor thrombus portends a dismal prognosis. Thus, prompt and accurate identification of tumor thrombus is crucial. We report here two unique cases of recurrent HGOS, presenting as thrombotic events, in order to increase awareness and index of suspicion among practitioners regarding this presentation. Additionally, we review 14 previously reported pediatric cases of cardiovascular metastatic HGOS.
Subject(s)
Bone Neoplasms , Osteosarcoma , Pulmonary Embolism , Thrombosis , Adolescent , Bone Neoplasms/diagnostic imaging , Bone Neoplasms/pathology , Female , Heart Atria/diagnostic imaging , Heart Atria/pathology , Heart Neoplasms/diagnostic imaging , Heart Neoplasms/pathology , Heart Neoplasms/secondary , Humans , Neoplasm Metastasis , Osteosarcoma/diagnostic imaging , Osteosarcoma/drug therapy , Osteosarcoma/pathology , Pulmonary Embolism/diagnostic imaging , Pulmonary Embolism/pathology , Thrombosis/diagnostic imaging , Thrombosis/pathologyABSTRACT
BACKGROUND: Atrial transseptal puncture (TSP) for cardiac catheterization procedures remain challenging in children and adults with complex congenital heart disease (CHD). OBJECTIVES: We sought to evaluate our experience using radiofrequency (RF) current via surgical electrocautery needle for TSP to facilitate diagnostic and interventional procedures. METHODS: Retrospective chart review of all patients (pts) who underwent TSP using RF energy (10-25 W) via surgical electrocautery from three centers from January 2011 to January 2017 were evaluated. Echocardiograms were reviewed to define the atrial septum as normal and complex (thin aneurysmal, thick/fibrotic, synthetic patch material, and extra cardiac conduit). RESULTS: A total of 54 pts underwent 55 successful TSP. Median age was 12.5 years (1 day-54 years) and weight was 52.7 kg (2-162). Indications for TSP included; EP study and ablation procedures in structurally normal hearts (n = 24) and in complex atrial septum/CHD and structural heart disease pts (n = 30): Electrophysiology study and ablation in 4, diagnostic catheterization in 9, and interventional procedures in 17 pts were performed. Atrial TSP was successful in 54/55 (98%). Atrial perforation with tiny-small pericardial effusion not requiring intervention was noted in 2 pts. TSP was unsuccessful in one critically ill neonate with unobstructed TAPVR and restricted atrial septum who experienced cardiac arrest requiring CPR, ECMO, and emergent surgery. CONCLUSIONS: RF current delivery using surgical electrocautery for TSP is a feasible and an effective option in patients with complex CHD for diagnostic, interventional, and electrophysiology procedures.
Subject(s)
Atrial Septum , Cardiac Catheterization/methods , Catheter Ablation/methods , Electrocoagulation/methods , Heart Defects, Congenital/diagnosis , Heart Defects, Congenital/therapy , Adolescent , Adult , Atrial Septum/diagnostic imaging , Atrial Septum/physiopathology , Cardiac Catheterization/adverse effects , Cardiac Catheterization/instrumentation , Catheter Ablation/adverse effects , Catheter Ablation/instrumentation , Child , Child, Preschool , Echocardiography, Doppler, Color , Echocardiography, Transesophageal , Electrocoagulation/adverse effects , Electrocoagulation/instrumentation , Equipment Design , Feasibility Studies , Female , Heart Defects, Congenital/complications , Heart Defects, Congenital/physiopathology , Hemodynamics , Humans , Infant , Infant, Newborn , Male , Michigan , Middle Aged , Needles , Predictive Value of Tests , Punctures , Radiography, Interventional , Retrospective Studies , Texas , Treatment Outcome , Young AdultABSTRACT
OBJECTIVES: To describe the early multi-center, clinical experience with the Medtronic Micro Vascular Plug™ (MVP) in children with congenital heart disease (CHD) undergoing vascular embolization. BACKGROUND: The MVP is a large diameter vascular occlusion device that can be delivered through a microcatheter for embolization of abnormal blood vessels. METHODS: A retrospective review of embolization procedures using the MVP in children with CHD was performed in 3-centers. Occlusion of patent ductus arteriosus using the MVP was not included. RESULTS: Ten children underwent attempted occlusion using the MVP. The most common indication to use the MVP was failed attempted occlusion using other embolic devices. Five, single ventricle patients (median age 3-years, median weight 14.9 kg) underwent occlusion of veno-venous collaterals following bidirectional Glenn operation. Three patients (Median age 8 years) underwent occlusion of coronary artery fistulae (CAF). Two patients (age 7 months and 1 year) underwent occlusion of large aorto-pulmonary collaterals. A 7-day-old child with a large CAF required 2 MVPs and an Amplatzer Vascular Plug (AVP-II) for complete occlusion. Occlusion of all other blood vessels was achieved using a single MVP. One MVP embolized distally in an 8-years-old child with a large CAF. There were no other procedural complications or during follow-up (median 9 months). CONCLUSIONS: The MVP is a new, large-diameter vascular embolization device that can be delivered through a microcatheter. It may play an important role in providing highly effective occlusion of abnormal vessels in children.