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Background: Transcatheter tricuspid valve-in-valve (ViV) replacement has yielded good hemodynamic outcomes in the treatment of dysfunctional bioprosthetic valves (BPVs). Intentional fracture of certain rigid BPV frames, if feasible, allows a larger implanted valve when compared with implant into an unfractured BPV. There remains limited data on the feasibility of tricuspid valve frame fracture., Aims: Evaluate the feasibility of transcatheter tricuspid ViV replacement with fracture of the underlying BPV ring., Methods: An international multicenter registry of tricuspid ViV replacement with intentional tricuspid valve frame fracture was created. Demographic data along with procedural characteristics, outcomes, and follow-up data were collected. Comparison was made to the pre- and post-ViV replacement with fracture of the tricuspid valve frame conditions., Results: Ten patients from six centers were included with a median age and weight of 29 years and 67.3 kg respectively. Tricuspid valve frame fracture was performed using a median balloon diameter 3 mm (IQR 3-5) larger than the true inner diameter (ID). The final ID was a mean of 1.5 mm (95% CI: 0.35, 2.64: p < 0.05), and median 1.1 mm (0.5, 2.1) larger than the reported true ID of the surgical BPV after ViV replacement. The mean tricuspid inflow gradient by echocardiogram decreased by 6.65 mmHg (95% CI: 4.14, 9.15: p < 0.001). All procedures were without complication, specifically there was no heart block, pericardial effusion, or right coronary disruption., Conclusion: Intentional tricuspid valve frame fracture with tricuspid ViV replacement is feasible and can increase the valve orifice potentially reducing the risk of ViV patient prosthesis mismatch and is not associated with significant complications., (© 2024 The Author(s). Catheterization and Cardiovascular Interventions published by Wiley Periodicals LLC.)

Background: The Alterra adaptive prestent is a novel self-expanding device designed to provide a landing zone for the 29 mm SAPIEN 3 valve to treat pulmonary regurgitation in patients with a right ventricular outflow tract that is too large for a balloon expandable valve alone. The mechanism of fixation for the Alterra prestent is radial force from the self-expanding stent frame, combined with a unique set of flared "tines" that protrude from both ends of the stent., Aims, Methods, and Results: In this report, we describe 6 patients who underwent uncomplicated transcatheter pulmonary valve replacement with an Alterra adaptive prestent and SAPIEN 3 valve and had surveillance chest computed tomography (CT) scans performed 1 day to 21 months after implant. In each patient, the CT scan demonstrated extravascular extension of a portion of the Alterra prestent, without clinical sequelae, but with extension into the ascending aorta in 1 patient and contact with the ascending aorta, left pulmonary vein, or left atrial appendage in 3 others., Conclusions: Surveillance CT imaging shows that the Alterra prestent can perforate the pulmonary artery and/or right ventricle. Although no sequelae were seen in these patients, prestent perforation has the potential to be clinically important. Implanters should be aware of this finding and its potential implications. As experience with the Alterra prestent grows, it will be important to further define the risk factors, incidence, and implications of this phenomenon., (© 2024 Wiley Periodicals LLC.)

Background: Percutaneous pulmonary valve implantation (PPVI) is a non-surgical treatment for right ventricular outflow tract (RVOT) dysfunction. During PPVI, a stented valve, delivered via catheter, replaces the dysfunctional pulmonary valve. Stent oversizing allows valve anchoring within the RVOT, but overexpansion can intrude on the surrounding structures. Potentially dangerous outcomes include aortic valve insufficiency (AVI) from aortic root (AR) distortion and myocardial ischemia from coronary artery (CA) compression. Currently, risks are evaluated via balloon angioplasty/sizing before stent deployment. Patient-specific finite element (FE) analysis frameworks can improve pre-procedural risk assessment, but current methods require hundreds of hours of high-performance computation., Methods: We created a simplified method to simulate the procedure using patient-specific FE models for accurate, efficient pre-procedural PPVI (using balloon expandable valves) risk assessment. The methodology was tested by retrospectively evaluating the clinical outcome of 12 PPVI candidates., Results: Of 12 patients (median age 14.5 years) with dysfunctional RVOT, 7 had native RVOT and 5 had RV-PA conduits. Seven patients had undergone successful RVOT stent/valve placement, three had significant AVI on balloon testing, one had left CA compression, and one had both AVI and left CA compression. A model-calculated change of more than 20% in lumen diameter of the AR or coronary arteries correctly predicted aortic valve sufficiency and/or CA compression in all the patients., Conclusion: Agreement between FE results and clinical outcomes is excellent. Additionally, these models run in 2-6 min on a desktop computer, demonstrating potential use of FE analysis for pre-procedural risk assessment of PPVI in a clinically relevant timeframe., (© 2024 The Authors. Catheterization and Cardiovascular Interventions published by Wiley Periodicals LLC.)

Background: Morbidity with surgical systemic-to-pulmonary artery shunting (SPS) in infants ≤2.5 kg has remained high. Patent ductus arteriosus (PDA) stenting may be a valid alternative. The objective of this study is to evaluate outcomes following PDA stenting in patients ≤2.5 kg from four large tertiary centers., Methods: Retrospective review of all neonates ≤2.5 kg with duct-dependent pulmonary circulation who underwent PDA stenting. Procedural details, pulmonary arterial growth, reinterventions, surgery type, and outcomes were assessed., Results: PDA stents were implanted in 37 of 38 patients attempted (18 female) at a median procedural weight of 2.2 kg (interquartile range [IQR], 2-2.4 kg). Seven patients (18%) had a genetic abnormality and 16 (42%) had associated comorbidities. The median intensive care unit stay was 4 days (IQR, 2-6.75 days), and the median hospital stay was 20 days (IQR, 16-57.25). One patient required a rescue shunt procedure, with three others requiring early SPS (<30 days postprocedure). Twenty patients (54%) required reintervention with either balloon angioplasty, restenting, or both. At 6-month follow-up, right pulmonary artery growth (median z-score -1.16 to 0.01, p = 0.05) was greater than the left pulmonary artery (median z-score -0.9 to -0.64, p = 0.35). Serious adverse effects (SAEs) were seen in 18% (N = 7) of our cohort. One patient developed an SAE during planned reintervention There were no intraprocedural deaths, with one early procedure-related mortality, and three interstage mortalities not directly related to PDA stenting., Conclusions: PDA stenting in infants ≤2.5 kg is feasible and effective, promoting pulmonary artery growth. Reintervention rates are relatively high, though many are planned to allow for optimal growth before a definitive operation., (© 2022 Wiley Periodicals LLC.)

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., (© 2020 Wiley Periodicals LLC.)

Objective: To assess the outcomes of the use of the percutaneous Impella RP device (Abiomed, Danvers, MA) in adolescents and young adults., Background: Results of the Impella RP device have been reported in adults, but a multicenter experience in adolescents and young adults has yet to be reported., Methods: Patients ≤21 years of age who underwent implantation of an Impella RP device for refractory right heart failure from June, 2016 to April, 2018 at nine U.S. Centers were included., Results: A total of 12 adolescents, median age of 18 (14-21) years and median weight 74.4 (49-112.4) kg underwent Impella RP implantation (INTERMACS Profile 1 in nine and Profile 2 in three patients. The central venous pressure decreased from 20 (16-35) to 12 (7-17) mmHg, (p = .001). One patient was concomitantly supported with an intra-aortic balloon pump (IABP) and the rest with a percutaneous/surgically placed left ventricular assist device. There was one adverse event related to the Impella RP device (thrombosis requiring explant). The support duration was 6.5 days (4.8 hr-18.4 days) and survival to hospital discharge was 83%. At a median follow-up of 11 months (5 days-2.5 years), 8 of 12 (67%) patients are alive., Conclusions: In this multicenter experience, the Impella RP device was found to be efficacious and safe when used in adolescents and young adults. Further studies are warranted to identify suitable young/pediatric candidates for Impella RP therapy for right heart failure., (© 2020 Wiley Periodicals, Inc.)

Background: Carotid artery (CA) and axillary artery (AA) access are increasingly used for transcatheter stenting of the patent ductus arteriosus (PDA), although reports are limited., Methods: The Congenital Catheterization Research Collaborative (CCRC) reviewed multicenter data from infants who underwent PDA stenting via the CA or AA approach from 2008 to 2017, and compared outcomes to those of infants undergoing PDA stenting via the femoral artery (FA) approach. Post-procedure ultrasound (US) imaging was reviewed., Results: Forty-nine infants underwent PDA stenting from the CA (n = 43) or AA (n = 6) approach, compared with 55 infants who underwent PDA stenting from the FA approach. The PDA was the sole pulmonary blood flow (PBF) source in 61% of infants in the CA/AA cohort, compared with 33% of the FA cohort (p < .01). Ductal tortuosity for CA/AA cohort was Type I (straight) in 10 (20%), Type II (one turn) in 17 (35%), and Type III (multiple turns) in 22 (45%) infants and reflected a greater degree of tortuosity when compared to the FA cohort (p < .01). In 17 infants with CA/AA approach, the "flip technique" was used, and was associated with shorter procedure times for highly tortuous PDA (Type III) patients. Rates of procedural complications were similar across access sites. Most common complications were access site injury (thrombus or bleeding) and stent malposition. No complications were specifically related to the "flip technique.", Conclusions: Use of CA and AA approach for PDA stenting was found to be more commonly employed in sole source PBF and highly tortuous PDAs. Procedural modifications such as the "flip technique" may lead to shorter procedure times. CA and AA approaches are associated with a similar burden of procedural or late complications. Post-procedural surveillance of the CA and AA is suggested, given the incidence of vascular findings on US., (© 2019 Wiley Periodicals, Inc.)

Objectives: To describe our initial experience with pediatric transcatheter aortic valve replacement., Background: Transcatheter aortic valve replacement (TAVR) has been approved and used to treat calcific aortic stenosis in adult patients. Select pediatric patients with congenital heart disease (CHD) who are poor candidates for conventional surgical aortic valve replacement can benefit from TAVR., Methods: A retrospective review was performed to identify and describe pediatric patients with CHD who underwent transcatheter or hybrid aortic valve replacement using a Melody Valve (Medtronic, Minneapolis, MN), or Sapien S3/XT valve (Edwards Life sciences LLC, Irvine, CA). Patients in whom transcatheter valves were implanted on cardiopulmonary bypass were included. Imaging data, procedural elements, and clinical follow-up data were collected to evaluate acute and short-term results., Results: A total of eight pediatric patients underwent treatment of aortic valvular disease using balloon expandable valves and delivery systems. Two patients had Melody valve implantation and six received a Sapien valve (one XT/five S3). In one patient, a Melody valve was placed surgically, failed, and was replaced with a Sapien valve 2 years later. Two patients were treated using a standard transfemoral route, four had the valve delivered on cardiopulmonary bypass via a median sternotomy, one was placed with a transapical approach, and one via a carotid cut down. Patients were followed for an average 16 months (range 1-208 weeks). There were no early or late deaths in this cohort. There were no embolic events, and all valves worked well in the immediate postoperative period. Both Melody implants developed moderate to severe regurgitation at 2 years and 4 years, respectively, and both required replacement at that time. One Sapien 3 valve developed a paravalvular leak that required reintervention within 6 months of implantation., Conclusions: Transcatheter valves offer a reasonable alternative to traditional surgical aortic valve replacement in certain pediatric patients who are suboptimal surgical candidates. Hybrid approaches and valve delivery on cardiopulmonary bypass has been used in smaller patients. Long-term performance of these valves in young patients has not been studied., (© 2019 Wiley Periodicals, Inc.)

Objectives: To describe a novel technique for mechanical thrombectomy (MT) in young children., Background: Acute thrombosis in children may be a cause of significant morbidity or mortality. MT options in children are limited due to patient and vessel size, prompting consideration of innovative approaches., Methods: Two-center review of children with symptomatic non-cerebral thrombotic vessel occlusion. A novel approach to MT was performed using a deployed but unreleased amplatzer vascular plug (AVP) to "scrape" the target vessel in retrograde fashion, thereby harvesting the thrombus via the access sheath., Results: AVP-MT was performed in four patients at a median age of 2 months (range: 1 day-11 months) and median weight of 5.6 kg (1.8-10.9). In two cases, AVP-MT was performed in isolation in neonates on cervical extracorporeal membrane oxygenation (ECMO) support with cannula-associated obstructive aortic and brachiocephalic thrombus. AVP-MT was also performed as adjunctive therapy in a patient with single ventricle physiology and pulmonary artery thrombosis and in an infant with mitral valve endocarditis and femoral arterial thromboembolism. In all cases, AVP-MT was used to successfully remove thrombus from the target vessel and restore arterial flow, without procedural complications. Recurrent thrombosis occurred in both neonates, due to persistence of the ECMO cannula, with subsequent mortality. The other children were free of recurrent thrombus at 2 and 34 months., Conclusions: Acute relief of symptomatic thrombosis may be achieved using AVP-MT in small children, although thrombosis frequently recurs, and clinical prognosis may remain poor. This strategy should be considered when alternative MT treatment options are not applicable., (© 2019 Wiley Periodicals, Inc.)

Objectives: To define patient and ventricular size parameters to guide Impella device (Abiomed, Inc., Danvers, MA) placement for mechanical circulatory support (MCS) in small pediatric patients (10-30 kg)., Background: There are few options for MCS in children, and there are no data on minimum patient size requirements for placement of the Impella 2.5 device., Methods: This was a multicenter study of echocardiographic and magnetic resonance imaging (MRI) derived dimensions of the left ventricle (LV) length and ascending aorta used to define minimum size parameters that are necessary for the placement of the Impella catheter., Results: Data were collected from 44 cardiac MRIs conducted in healthy pediatric patients and 39 echocardiograms performed in pediatric patients with cardiomyopathy prior to surgical ventricular assist device (VAD) placement. The Impella 2.5 catheter is 7.5 cm from the pigtail to the aortic annulus marker, thus requiring an LV apical length of 7.5 cm to allow the device to function in an unconstrained fashion. In the cohort of patients undergoing consideration for VAD placement, a minimum LV length of 7.5 cm corresponded to a height of 122 cm, weight of 23 kg, and body surface area (BSA) of 0.89 m 2 . In the MRI cohort, this corresponded to a height of 121 cm, weight of 23.9 kg, and BSA of 0.89 m 2 ., Conclusion: MCS with Impella devices is feasible in pediatric patients. This study defines anthropomorphic and anatomic measurements to guide providers in patient selection for MCS using the Impella devices., (© 2019 Wiley Periodicals, Inc.)

Objective: Comparison of outcomes using bare metal (BMS) and drug-eluting (DES) stents in pulmonary vein stenosis (PVS)., Background: PVS is a serious condition with frequent restenosis after surgical and percutaneous interventions. After experiencing encouraging results with DES, we sought to compare outcomes of BMS and DES in native and post-surgical PVS., Methods and Results: A retrospective review of all patients who underwent stent implantation between 08/93 and 11/17 for PVS at Texas Children's Hospital was performed. BMS were used to treat 58 lesions in 37 patients and 105 DES used to treat 105 lesions in 41 patients. Mean age at first stent implant was 2.9 ± 3.5 years in BMS and 16.2 ± 18.8 months in DES group. Of those with follow-up catheterization, mean lumen loss rate from stent implant to first follow-up catheterization was 0.85 ± 1.47 mm/month over 6.4 ± 6.4 months in the BMS group (n = 44 lesions) compared to 0.16 ± 0.31 mm/month over 6.8 ± 7.4 months in the DES group (n = 86 lesions), p < .01. Follow-up for the BMS group was 14 months (6 days-22.3 years), with 13 mortalities, eight lesions were re-stented and six complete occlusions were noted. Follow-up for DES group (including four cross-overs) was 17.5 months (3 days-9 years), with 10 mortalities, seven lesions were re-stented, 11 had complete occlusion, 20 new adjacent lesions in the same vessel underwent stenting and 12 stents were intentionally fractured., Conclusion: DES have significantly lowered lumen loss rate when compared to BMS at medium term follow-up and can be fractured to enable larger diameters. Availability of larger diameter DES would be ideal., (© 2019 Wiley Periodicals, Inc.)

Objectives: We aimed to assess the experience using a percutaneous axillary artery approach for insertion of arterial ductal stents in patients with critical right ventricular outflow tract lesions at two tertiary pediatric cardiology centers., Background: Patent ductus arteriosus stenting is an accepted palliative alternative to BT shunts for neonates with critical right heart lesions. Access to tortuous ductus' may be challenging via the femoral artery, whereas the carotid artery presents a low risk of stroke. Recently, the axillary artery has been utilized for access in these patients., Methods: We performed a retrospective review of neonates who underwent stent placement or angioplasty using percutaneous axillary artery approach at two tertiary care centers from October 2016 to November 2018. Medical records were reviewed to ascertain demographic, clinical, and outcome data., Results: Axillary artery access was performed in 20 patients (16 primary ductal stents and 4 re-interventions) at a median (IQR) procedural weight of 3.4 (3-3.9) kg. Median (IQR) procedural time was 110 (75-150) min. The median (IQR) ICU stay and intubation times were 14 (0-94) hr and 5 (0-40) hr, respectively. There were three access-related vascular complications which were managed conservatively with no long-term effects. Two patients subsequently died due to non-procedure related causes., Conclusions: Ductal stenting via a percutaneous axillary artery approach is a viable option in neonates with critical right ventricular outflow tract lesions. This approach provides an additional access site for PDA stenting which may be utilized in patients with vertical duct morphology., (© 2019 Wiley Periodicals, Inc.)

Objectives: To devise a classification scheme for ductal morphology in patients with ductal dependent pulmonary blood flow (PBF) that can be used to assess outcomes., Background: The impact of ductal morphology on outcomes following patent ductus arteriosus (PDA) stenting is not well defined., Methods: Patients <1 year of age who underwent PDA stenting for ductal dependent PBF at the four centers comprising the Congenital Catheterization Research Collaborative (CCRC) were included. A classification scheme for PDA morphology was devised based on a tortuosity index (TI)-Type I (straight), Type II (one turn), and Type III (multiple turns). A subtype classification was used based upon the ductal origin., Results: One hundred and five patients underwent PDA stenting. TI was Type I in 58, Type II in 24, and Type III in 23 PDAs, respectively. There was a significant association between ductal origin and vascular access site (p < 0.001). Procedure times and need for >1 stent did not differ based on TI. Greater TI was associated with pulmonary artery (PA) jailing (p = 0.003). Twelve (11.4%) patients underwent unplanned reintervention, more commonly with greater TI (p = 0.022) and PA jailing (p < 0.001). At the time of subsequent surgical repair/palliative staging, PA arterioplasty was performed in 32 patients, more commonly when a PA was jailed (p = 0.048). PA jailing did not affect PA size at follow up., Conclusions: The proposed qualitative and quantitative PDA morphology classification scheme may be helpful in anticipating outcomes in patients with ductal dependent PBF undergoing PDA stenting., (© 2019 Wiley Periodicals, Inc.)

Background: Use of small diameter stents in young children and jailing of side branches pose significant challenges to future re-interventions. We sought to assess the capacity to induce longitudinal fractures in undersized stents to increase vessel diameter, and side cell fractures to enlarge stenotic jailed branches., Methods: Retrospective review of patients who underwent attempted intentional stent fractures (ISF) from 01/06-02/17., Results: Twenty-two patients, median age 4.4 (1.1-47.8) years, weighing 14.3 (6.9-102) kg underwent attempted ISF in 32 vessels. Initial stent implant occurred at a median age of 1.0 (0.1-34.1) years, at the following sites: pulmonary arteries (11), pulmonary veins (14), systemic veins (6), and aorta (1). Initial diameters of the stents were 3.5-12 mm. Thirteen vessels had overlapping stents. Using high-pressure balloons, longitudinal ISF was achieved in 23 and side cell ISF in eight vessels. One longitudinal ISF attempt was unsuccessful. Three lesions were immediately re-stented after longitudinal ISF, and three lesions treated with angioplasty (1) or stenting (2) after side cell ISF. Only one complication occurred (pseudoaneurysm in a pulmonary artery after longitudinal ISF requiring placement of a covered stent). At a median follow up of 2.0 years (2 days - 10.8 years), eight patients had 16 additional interventions for restenosis at site of ISF., Conclusions: ISF can be induced safely in a variety of vascular beds using high-pressure balloons both longitudinally or through side cells. Longitudinal ISF only rarely requires immediate placement of a new stent; however, late restenosis may occur, requiring re-stenting., (© 2018 Wiley Periodicals, Inc.)

Background: Interventional catheterization procedures may be needed for patients with severe renal failure who are dependent on dialysis. To avoid the risk of fluid overload and electrolyte derangement during complex procedures in this oliguric/anuric patient population, we performed intra-procedural dialysis, either continuous renal replacement therapy (CRRT) or continous cycling peritoneal dialysis (CCPD)., Methods: We performed a retrospective review of a cohort of pediatric patients, ages 0-18 years, with dialysis-dependent renal failure who received CRRT or CCPD during catheterization procedures from January 2013 to March 2016., Results: Eight patients underwent a total of nine interventional catheterization procedures while receiving intra-procedural dialysis. Median age was 4.5 years (range 8 months to 17 years) and weight, 11.6 kg (11.2-62.6 kg). Six patients had end-stage renal disease (ESRD) and two patients had acute kidney injury (AKI), one due to hepatorenal syndrome and one due to multifactorial causes associated with congenital heart disease. The most common reason for catheterization was occlusive venous thrombosis requiring recanalization. CRRT was used during five cases and CCPD during four cases. Median procedure time was 337 min (95-651 min) and median contrast dose 4.2 mL kg -1 (1.2-8.2 mL kg -1 ). Euvolemia was maintained based on pre- and post-catheterizations weights, and no significant electrolyte abnormalities occurred based on lab monitoring during and post-procedure., Conclusions: Intra-procedural dialysis using CRRT or CCPD enables even small pediatric patients with severe renal failure to undergo long and complex interventional catheterizations by reducing the risk of fluid overload and electrolyte abnormalities. Collaboration between nephrology, cardiology, and dialysis teams is necessary for successful management of this challenging patient population., (© 2017 Wiley Periodicals, Inc.)

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., (© 2017 Wiley Periodicals, Inc.)

Objectives: To describe the early multicenter, clinical experience with the Medtronic Micro Vascular Plug™ (MVP) for the occlusion of patent ductus arteriosus (PDA) in premature infants., Background: The MVP is a large diameter plug that can be delivered through a microcatheter for occlusion of abnormal blood vessels., Methods: A Retrospective review of PDA embolization procedures performed in two centers using the MVP was performed., Results: Fifteen premature infants underwent attempted PDA occlusion using the MVP. The gestational age and birth weight were 25.6 ± 2.5 weeks and 735 ± 251 g, respectively. The median weight and age at the time of the procedure were 1,210 g (700-3,500 g) and 4.5 weeks (2-12 weeks), respectively. Median procedure and fluoroscopy times were 45 and 6.5 min, respectively. The median radiation and contrast doses were 19.7 mGy and 2.4 mL/kg, respectively. Antegrade occlusion was successfully achieved in 13 patients <2 kg with only femoral venous access aided by echo guidance. The two patients >2 kg had arterial access and attempted retrograde occlusion; one of which was unsuccessful due to the PDA being short and wide. Complete closure was observed in 13 of 14 successful procedures (93%), with one patient having a small residual shunt that was not seen on follow-up. There were no complications related to the procedure or noted during follow-up (Median 11 months)., Conclusions: The MVP is a new, large-diameter vascular embolization device that may be useful for the occlusion of PDA in extremely small, premature infants. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Background: Vascular thromboses are a significant cause of morbidity and mortality in children. Data in children regarding catheter-based rheolytic and aspiration thrombectomy systems are limited. We sought to review the safety and efficacy of catheter-based rheolytic and aspiration thrombectomy systems in children., Methods: Data of all children having undergone thrombectomy using specialized rheolytic or aspiration systems were reviewed., Results: Thrombectomy was performed in 50 vessels in 21 patients, median age 1.9 months (8 days-18 yrs), median weight 4.3 (1.1-67.9) kg. Thrombectomy was performed using AngioJet in 16, Helix Clot Buster in 5, Fetch catheter in 8, Pronto catheter in 1, and a combination of other systems in 20 vessels (with AngioJet in 16). Thrombectomy was successful in 47/50 (94%) vessels in 18/21 (86%) patients with additional balloon/stent therapy or tPA administration performed in 16/18 (89%) of these patients. There were 2 (9.5%) major complications (both with AngioJet) consisting of asystole when thrombectomy was performed using activation times of >5 sec. At a median follow-up of 10 months (2 weeks-7 years), all 47 successfully treated vessels are patent, with 8/18 (44%) patients requiring reintervention with angioplasty/stent placement or repeat thrombectomy., Conclusions: Catheter-based thrombectomy systems are an important adjunctive tool in the treatment of children with thrombotic vessel occlusions. Significant hemodynamic compromise seen when using AngioJet may be minimized by using activation times of ≤5 sec. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Objectives: To describe the effectiveness of the Helex Septal Occluder (HSO) to close multiple atrial septal defects (mASDs). Background : Limited information is available describing closure of mASDs with the HSO., Methods: A total of 28 patients who underwent closure of mASDs with the HSO were identified by retrospective review of our catheterization database between 2001 and 2012. Procedural details and follow up information were collected., Results: Median age was 19.2 years, median weight 48 kg, with 10 (36%) patients weighing <25 kg. Indication for closure was RV enlargement (RVE) in all patients and additionally neurologic events occurred in 3/28 (11%). Median stop-flow diameter for the largest ASD was 14 (4-23) mm. One HSO was implanted in 21/28 (75%), 2 in 6/28 (21%), and 3 in 1/28 (4%). One embolization and one transient arrhythmia occurred with no sequelae. Immediate residual shunt was absent in 5/28 (18%), trivial in 15/28 (54%), small in 6/28 (21%), and moderate in 2/28 (7%). Of the 25 patients with ≥6 months follow-up (median 53 months), residual shunt was absent in 13/25 (52%), trivial in 5/25 (20%), and small in 7/25 (28%). RVE resolved in all but one patient with no other associated lesions and ≥6 months of follow-up. No patient with prior neurological event had recurrence at last follow-up., Conclusions: We conclude that closure of mASDs with ≥1 HSO is effective with a low complication rate. The ability of HSO devices to overlap or sandwich each other may facilitate safe implantation of multiple devices in smaller patients., (© 2013 Wiley Periodicals, Inc.)

Objectives: To identify complications and measures that can be undertaken to prevent complications from transhepatic central venous access., Background: Utility and safety data from a large experience of patients undergoing transhepatic venous access are lacking., Methods: The records of patients who underwent transhepatic venous access between June 2000 and October 2012 at The Center for Pediatric and Congenital Heart Disease at The Cleveland Clinic were reviewed., Results: One hundred twenty-four transhepatic procedures were performed in 81 patients. The median weight of the patients was 6.3 (2.2-94) kg at a median age of 7 months (2 weeks to 35 years). Diagnostic catheterizations were performed in 75, interventions in 39, and central venous line placement in 91 procedures. The median maximum sheath size inserted was 8 (4-14) French. There were 10 (8%) major adverse events in 8 procedures-bleeding related (n = 6 with 1 death as a result) or complete heart block with instability or requiring intervention (n = 4). Heart block persisted after the catheterization in three patients (2 days, 2 weeks, 1 month). Minor adverse events (transient heart block) occurred in 5 (4 %) procedures. Weight, age, and French size of sheath (P = 0.46, 0.84, and 0.18) were not associated with complications. In addition, time to gain access was not different between non-complicated and complicated cases (median 19.5 versus 15.1 min, P = 0.72). Diagnostic and interventional procedures were not associated with more complications compared with procedures involving central venous line placement alone (P = 0.5)., Conclusions: Transhepatic access is an extremely useful modality of access to the heart and vascular structures in some patients with complex heart disease. Prevention of complications should focus on minimizing bleeding risks and heart block., (© 2013 Wiley Periodicals, Inc.)

Objectives: Review mid-term follow-up of percutaneous intervention for post ablation total pulmonary vein occlusion (PVO)., Background: Feasibility of percutaneous intervention for PVO has been described, but information remains limited., Methods: Patients with total PVO were retrospectively identified from our catheterization database. Medical records, catheterization reports, and outpatient follow-up were reviewed., Results: Between April 2005 and February 2012, 16 patients were identified with a total of 18 PVOs. Symptoms included hemoptysis in 6/16 (46%), cough in 8/16 (50%), chest pain in 8/16 (50%), dyspnea in 13/16 (81%) with mean NYHA Class of 2.6 ± 0.6. Recanalization was accomplished in 14/18 (78%) veins: 11 treated with balloon dilation and 3 with stents. Median follow-up for 13/14 veins was 13 (0-39) months (one patient with one PVO is awaiting follow-up). Reocclusion occurred in 7/13 (54%) at mean follow-up of 3.6 ± 1.6 months (6/10 post-balloon dilation and 1/3 post-stenting). Despite reocclusion, the reference vessel diameter increased from 4.8 ± 2.4 to 8.5 ± 4.2 mm (P < 0.001) between the first and second catheterization. Re-recanalization and stent placement was accomplished in 5/6 (83%), with one reocclusion not attempted. At latest follow-up 9/13 (69%) recanalized vessels remained patent and percent flow to affected lung quadrant increased from 7.4 ± 3.4% pre-intervention to 14.3 ± 4.2% (P = 0.004). Mean NYHA Class improved to 1.4 ± 0.4 (P < 0.001)., Conclusions: Recanalization of total PVO can be accomplished with reasonable mid-term patency, improved symptoms, and lung perfusion. Reocclusion is common, but vessel growth is often observed allowing placement of a reasonably sized stent at a second intervention. Staged intervention is often necessary to maintain patency., (Copyright © 2013 Wiley Periodicals, Inc.)

After the Norwood procedure for palliation of hypoplastic left heart syndrome, there is still significant interstage and late mortality with often unclear etiology. An important, but possibly under-recognized complication of the Norwood operation is the potential for coronary insufficiency from pre-coronary stenosis due to kinking or scarring at the anastomosis between the native and neo-aorta. We report a case of a clinically thriving 10-month old infant status post bidirectional Glenn who had acute ischemic changes on electrocardiogram (ECG) during induction of anesthesia for elective bilateral herniorrhaphy. A discrete narrowing in the native aorta to neo-aorta anastomosis was identified. A stent was placed emergently to restore adequate coronary blood flow after failure of simple angioplasty to adequately improve the stenosis., (Copyright © 2011 Wiley Periodicals, Inc.)

Background: Pediatric physicians regularly face the problem of uncertain procedural anticoagulation in children, especially in neonates. We sought to evaluate the safety, plasma concentration (pharmacokinetics, PK), pharmacodynamics (PD), and dosing guidelines of bivalirudin when used as a procedural anticoagulant in pediatric percutaneous intravascular procedures., Methods and Results: Pediatric subjects undergoing percutaneous intravascular procedures for congenital heart disease were enrolled and received the current weight-based dose used in percutaneous coronary interventions (0.75 mg/kg bolus, 1.75 mg/kg/hr infusion). Blood samples for PK/PD analyses were drawn, and safety was evaluated by monitoring bleeding and thrombosis events. A total of 110 patients (11 neonates, 33 infants, 32 young children, and 34 older children) were enrolled; 106 patients received the protocol dose. The PK/PD response of bivalirudin was predictable and behaved in a manner similar to that in adults. Weight-normalized bivalirudin clearance rates were more rapid in neonates and decreased with increasing age. Bivalirudin concentrations were slightly lower in neonates, with a trend to an increase with age. Activating clotting time response was consistent with adult studies and prolonged in all age groups, and there was reasonable correlation between activating clotting time and bivalirudin plasma concentrations across all age groups. There were few major bleeding (2 of 110, 1.8%) or thrombotic events (9 of 110, 8.2%) reported., Conclusions: PK/PD response of bivalirudin in the pediatric population is predictable and behaves in a manner similar to that in adults. Using adult dosing, bivalirudin safely provided the expected anticoagulant effect in the pediatric population undergoing intravascular procedures for congenital heart disease., (Copyright © 2010 Wiley-Liss, Inc.)

One or more breaks in the wire frame of the HELEX Septal Occluder (W.L. Gore and Associates, Flaggstaff, Arizona) were identified in 5% of patients in the multicenter pivotal trial leading to FDA approval. Fractures of the perimeter frame have not previously been associated with any apparent deleterious clinical effects. We report a case in which the broken ends of wire at a frame fracture were located in a position that resulted in perforation of the anterior mitral valve leaflet. There was significant mitral regurgitation and the device was removed surgically. The possible etiologies and prevention of wire frame fractures are also discussed., (Copyright 2009 Wiley-Liss, Inc.)