Intra-stent aortic wall aneurysm formation after Be-graft covered stent implant.

Aortic wall injuries may occur after interventional treatment of aortic coarctation (CoA), especially after balloon angioplasty. We reported on a patient who presented with an intra-stent aneurysm formation after direct stenting of a native near atretic aortic CoA by using a BeGraft Aortic stent. This evidence supports the need to maintain a strict follow-up protocol. A computed tomography scan is mandatory, after covered stent implantation as well, especially in high-risk cases and even in the absence of any immediate apparent complication.

Novel application of the Diabolo technique to restrict pulmonary blood flow in a single ventricle patient with a right ventricle to pulmonary artery conduit.

Balancing pulmonary and systemic circulations in single ventricle patients with a conduit after Stage 1 palliation is challenging. A transcatheter intervention for excessive pulmonary blood flow would provide benefit. We report a case of a critically ill single ventricle patient with symptoms of excessive pulmonary blood flow after Stage 1 despite maximal medical therapy. The patient underwent percutaneous intraluminal downsizing of the right ventricle to pulmonary artery conduit using a novel application of the Diabolo-covered stent technique, with subsequent clinical improvement. A second catheterization was performed during the interstage period with successful dilation of the stent to achieve appropriate saturations. The Diabolo technique can be successfully employed in this population to restrict pulmonary blood flow and has the advantage of being adjusted during placement and in subsequent interventions.

Novel Uses of the SwiftNinja Steerable Microcatheter for Pediatric Cardiovascular Interventions.

In the present era, the intricacy of procedures undertaken by a pediatric interventional cardiologist has increased, primarily attributed to dealing with smaller, younger patients with more complex anatomies. To adapt to these smaller and more complex patients, we must adapt our interventions and our equipment to perform these procedures. This article outlines various innovative applications of the SwiftNinja steerable microcatheter within the pediatric cardiac catheterization laboratory.

Transfemoral Perimembranous Ventricular Septal Defect Device Closure in Infants Weighing ≤ 10 kg.

Transcatheter closure of Perimembranous VSDs (PMVSD) remains challenging particularly in infants. The aim of this study is to evaluate the efficacy and safety of transfemoral PMVSD device closure in infants weighing ≤ 10 kg in a single centre. Retrospective review of departmental databases and medical charts to define patient cohort and collect demographic, procedural and follow-up data. Between July 2014 and March 2021, 16 patients underwent attempted transfemoral PMVSD device closure (12 retrograde) at a median age of 11 months (interquartile range [IQR] 9-15.5) and a median weight of 8.3 kg (IQR 7.2-9.5). All patients were either symptomatic, had progressive left heart dilation or had VSD associated valve regurgitation. Median defect size on pre-procedural transoesophageal echocardiography was 6.8 mm (IQR 6-8.5). Median device waist size was 6 mm (IQR 4.5-8). Successful device placement was achieved in 14 patients (88%). One patient developed moderate aortic and tricuspid valve regurgitation upon retrograde and antegrade device deployment, respectively, and subsequently underwent surgical closure. The second patient developed progressive aortic regurgitation (AR) 2 days post procedure, and also underwent surgical removal with no residual AR. There was no cases of device embolization and no femoral arterial compromise. On median follow-up of 40.5 months (IQR 25-64), none of the patients developed complete heart block. Three patients (18.75%) had small residual shunts at latest follow-up which have not required any further intervention. Device closure of PMVSD's in children weighing ≤ 10 kg is feasible and safe with good procedural success rates. Use of both the antegrade and retrograde approaches may be necessary depending on anatomical variances.

Shortening of Palmaz Genesis XD stents by longitudinal compression in pediatric patients with pulmonary vein stenosis: Bench-testing and case series.

The Palmaz Genesis XD stents (Cordis®, Cardinal Health, Dublin, OH) are an ideal option for stenting vessels in pediatric patients due to their ability to be re-dilated to large diameters to accompany children's somatic growth. Unfortunately, their length limits their utility for pulmonary vein stenting in small children, due to the risk of protrusion into the left atrium or into distal pulmonary vein branches. We describe a stent shortening technique by longitudinally compressing them prior to deployment, which may enhance their applicability in pediatric pulmonary vein stenosis.

Prospective multicenter study of the breakable babystent for treatment of aortic coarctation in newborns and infants.

To assess the efficacy and safety of a breakable BabyStent to treat complex aortic coarctation (CoA) in early childhood. Although recommended in several guidelines, there is no approved aortic stent for young infants, because of the dilemma between two mandatory requirements: expandable up to adult size on the one hand, and small enough to fit through a baby's femoral artery on the other. Prospective interventional, multi-center clinical trial with the breakable Osypka BabyStent® (OBS). The OBS is a low-profile, 15-mm long cobalt-chromium stent, pre-mounted on a 6 mm balloon and inserted via a 4 Fr sheath. After implantation, its diameter is adjustable from 6 to 12 mm by balloon dilation. Further dilation opens predefined joints enabling unrestricted growth. Nineteen patients (9 male), median age 112 days (range: 7-539), median body weight 5.6 kg (range: 2.4-8.4) were deemed high risk and underwent stent implantation. Of those, 74% suffered from re-CoA following surgery, 53% had additional cardiac and 21% noncardiac malformations. Our primary combined endpoint was fulfilled: All stents were implanted in the desired region, and a >50% intrastenotic diameter-extension was achieved in 15 patients (78.9%, 80% confidence interval [62.2; 90.5], 95% confidence interval [54.4; 93.9]). Secondary endpoint confirmed that the OBS fits the baby's femoral vessel diameter. All children survived the procedure and 12-month follow-up. This stent enables percutaneous stenting of complex aortic coarctation to treat high-risk newborns and infants.

Anomalous coronary artery in Tetralogy of Fallot-Feasibility of right ventricular outflow tract stenting as initial palliation.

This study addresses the outcome of right ventricle outflow tract (RVOT) stenting in Tetralogy of Fallot (ToF) with anomalous coronaries crossing the RVOT. RVOT stenting in ToF patients has emerged as an alternative to Blalock Taussig shunting. This is a single center study of patients who underwent RVOT stenting for symptomatic ToF at Birmingham Children's Hospital between 2005 and 2020. A total of 122 patients underwent RVOT stenting as initial palliation over a 15-year period, 10 patients had anomalous coronaries crossing the RVOT (study group) and 112 not (comparative group). Median age of the study group was 72.5 days (interquartile range [IQR]: 28-103) with a weight of 4.7 kg (IQR: 3.5-4.9). No significant differences were found between the two groups regarding the patients' weights and ages, procedure and screening times, or hospital stay. Four had valve sparing stenting. Oxygen saturations increased from a median of 75.5% (IQR: 70-82) to 94.5% (IQR: 90-95), p < 0.002. Postprocedure median hospital stay was 3 days (IQR: 2-6). Six patients underwent interstage catheterization reintervention and one needed early surgical palliation due to stent suboptimal position. Complete repair could be delayed for a median of 11.1 months (IQR: 5.6-19.2). At surgical repair, the patients had a median age of 12.3 months (IQR: 7.5-25.6) and weight of 7.7 kg (IQR: 6.8-10.8). There were no deaths. RVOT stenting in ToF with anomalous coronaries is safe and effective. Dilatable stents should be used when two-stage delayed conduit repair is the default approach.

Interpreting Quality Improvement When Introducing New Technology: A Collaborative Experience in ASD Device Closures.

The objective of this study was to evaluate the impact of the regular introduction of new technologies into interventional cardiac catheterization procedures, in this case new atrial septal defect (ASD) closure devices, while conducting a multi-center collaborative initiative to reduce radiation usage during all procedures. Data were collected prospectively by 8 C3PO institutions between January 1, 2014 and December 31, 2017 for ASD device closure procedures in the cardiac catheterization lab during a quality improvement (QI) initiative aimed at reducing patient radiation exposure. Radiation exposure was measured in dose area product per body weight (µGy*m2/kg). Use of proposed practice change strategies at the beginning and end of the QI intervention period was assessed. Radiation exposure was summarized by institution and by initial type of device used for closure. This study included 602 ASD device closures. Without changes in patient characteristics, total fluoroscopy duration, or number of digital acquisitions, median radiation exposure decreased from 37 DAP/kg to 14 DAP/kg from 2014 to 2017. While all individual centers decreased overall median DAP/kg, the use of novel devices for ASD closure correlated with a temporary period of worsening institutional radiation exposure and increased fluoroscopy time. The introduction of new ASD closure devices resulted in increased radiation exposure during a QI project designed to reduce radiation exposure. Therefore, outcome assessment must be contextualized in QI projects, hospital evaluation, and public reporting, to acknowledge the expected variation during innovation and introduction of novel therapies.

Preliminary testing and evaluation of the renata minima stent, an infant stent capable of achieving adult dimensions.

OBJECTIVES: This study sought to obtain in vivo data on a new stent and delivery system specifically designed for implantation in infants with the ability to be enlarged to adult dimensions. BACKGROUND: There are no endovascular stents designed for or approved for use in infants, nor is there a stent capable of being implanted at infant vessel diameters and achieving adult size while maintaining structural integrity. The Minima stent was designed to address these needs. METHODS: This study was performed in 6 piglets who underwent implantation of 22 Minima stents into the following locations: aorta (n = 11), branch pulmonary arteries (n = 6), and central veins (n = 5). RESULTS: Successful deployment occurred in 21/22 attempts. Two instances of post-deployment migration occurred. Stents were re-expanded at 1, 2, 3 and 5 months after implant. All stents regardless of location could be re-dilated to the intended diameter to keep pace with somatic growth (implant diameter 6.9 +/- 1.2 mm; final diameter 16.1 mm +/- 1.4 mm). Histopathology at 1 and 5 months demonstrated widely patent vessel lumens with stent apposition to vessel wall, early mild inflammatory response surrounding stent struts, typical vascular damage and healing response to acute dilation and a progressive smooth neointimal growth covering stent struts over time. CONCLUSIONS: In this in vivo study of the Minima stent, there was high implant success, predictable re-dilatability to adult diameters and favorable histopathology. Further study is warranted.

Managing confounding and effect modification in pediatric/congenital interventional cardiology research.

Measuring the effect of a treatment on outcomes is an important goal for research in pediatric/congenital interventional cardiology. The breadth of anatomic and physiologic variations, patient ages, and genetic syndromes and noncardiac comorbid conditions all represent sources of potential confounding and effect modification that are major obstacles to this goal. If not accounted for, these factors can obscure the "true" treatment effect and lead to spurious conclusions about the relative efficacy and/or safety of therapies. In this review, we discuss the importance of confounding and effect modification in pediatric/congenital interventional cardiology research. We define these terms and discuss strategies (both in study design and data analysis) to mitigate error introduced by confounding and effect modification. The importance of confounding by indication in pediatric/congenital cardiology is discussed along with specific methods to address it.

Ductal stent endocarditis resulting in a large aortic pseudoaneurysm.

An infant with ductal dependent pulmonary blood flow who underwent neonatal ductal stenting and, 4 months later, developed ductal stent endocarditis due to Streptococcus gallolyticus subsp. pasteurianus was described. The infection was associated with a moderate aortic pseudoaneurysm and the patient was treated with antibiotics as well as surgical aortic pseudoaneurysm repair. This novel and unusual complication of ductal stent placement warrants reporting.

Apical muscular ventricular septal defect closure via hybrid approach using a right ventricular stay suture.

Transcatheter closure of large apical muscular ventricular septal defects (VSDs) can be performed via transfemoral or hybrid approach. A very large apical muscular VSD was closed via a hybrid approach. A strategy for deployment of a right ventricular stay suture was utilized to minimize the risk of device embolization without the use of bypass and without externalization of a portion of the device.

Expanding percutaneous treatment of mitral valve diseases: Transcatheter closure of mitral valve leaflet perforation.

Mitral valve perforation is a rare cause of mitral regurgitation. We present a case of a 16-year-old patient with mitral valve regurgitation after redo-cardiac surgery for recurrent subaortic stenosis. Transthoracic echocardiography revealed a mitral regurgitation with an eccentric jet causing a significant regurgitation documented by the presence of a convergence flow over the hole. This finding was corroborating by transesophageal echocardiography locating the perforation from the region of A2 scallop. Three-dimensional transesophageal echocardiography confirmed these findings and played a key role guiding the procedure. Typical approach is usually a cardiac surgical procedure based on repair the perforation, but the mitral orifice was successfully closed percutaneously using an Amplatzer Duct Occluder II (ADO II; Abbott Vascular, IL).

Procedural Predictors and Outcomes of Percutaneous Secundum Atrial Septal Defect Closure in Children Aged <6 Years.

BACKGROUND: Percutaneous atrial septal defect (ASD) closure is the treatment of choice for patients with a suitable ASD anatomy; however, the procedural characteristics and outcomes in children aged <6 years are unclear. The feasibility and safety of percutaneous ASD closure in children aged <6 years was evaluated and the predictors of procedural failure and challenging cases were identified.Methods and Results:Patients from a single center between 2006 and 2018 (n=407) were retrospectively evaluated. There were 265 (65.1%) female patients. The median age at the time of the procedure and ASD size were 3.4 (0.9-5.9) years and 13.3 (3.8-27.0) mm, respectively. Medical records and echocardiographic images were analyzed. A challenging case was indicated by the use of non-conventional techniques. The procedure was completed in 399 patients (98.0%). Post-procedural acute complications occurred in 5 patients, including 1 with device embolization. Two patients underwent surgical device removal. During the follow up (30.3 [3.6-140.8] months), aggravated mitral regurgitation occurred in 5 patients. A multivariate logistic regression revealed large-sized ASD as a predictor of procedural failure (odds ratio=1.828, 95% confidence interval: 1.139-2.934, P=0.012) and challenging cases (odds ratio=1.371, 95% confidence interval: 1.180-1.593, P<0.001). CONCLUSIONS: Percutaneous ASD closure is feasible and safe in children aged <6 years; however, patients with large-sized ASD are at high risk of procedural failure and becoming a challenging case.

Transcarotid Approach to Ventricular Septal Defect Closure in Small Infants.

Perimembranous ventricular septal defect closure in small infants has traditionally been a surgically treated defect, although alternative hybrid strategies are emerging. We aim to describe a novel approach to retrograde device closure of clinically relevant perimembranous ventricular septal defects in small infants via carotid cutdown. A retrospective review of all patients managed with attempted carotid cutdown for device closure of a perimembranous ventricular septal defect was recorded at a single tertiary cardiac centre. We summarized data on successful device deployment, conversion to open repair, complications, and length of stay. Eighteen infants with median (IQR) age of 7 months (5-9 months) and weight of 7.1 kg (6.5-7.8 kg) with clinically relevant PMVSD underwent attempted retrograde closure via carotid cutdown. Median (IQR) defect size was 8 mm (7-9 mm). Successful device deployment without significant aortic or tricuspid valve interference occurred in 15 (83%) patients. Three patients were converted to open repair, one following damage to the tricuspid valve apparatus. Median (IQR) hospital stay was 1 day (1-3 days). There were no complications related to carotid cutdown. Retrograde device closure of hemodynamically significant PMVSD is feasible and effective in small infants. Decision to convert to surgical repair should be made early if suboptimal device placement occurs. Carotid evaluation should be performed to rule out any access-related complications.

Novel Minimal Radiation Approach for Percutaneous Pulmonary Valve Implantation.

The aim of the study is to evaluate the impact of multimodality imaging technology during percutaneous pulmonary valve implantation (PPVI). Among percutaneous procedures, PPVI traditionally has one of the highest patient radiation exposures. Different protocol modifications have been implemented to address this problem (i.e., improvements in guidance systems, delivery systems, valve design, post-implantation evaluation). Although the effectiveness of individual modifications has been proven, the effect of an approach which combines these changes has not been reported. We performed a retrospective chart review of 76 patients who underwent PPVI between January 2018 and December 2019. Patients were classified in "Traditional protocol," using routine biplane angiography and/or 3D rotational angiography (3DRA); and "Multimodality protocol" that included the use of VesselNavigator for guidance, selective 3DRA for coronary evaluation, Long DrySeal Sheath for valve delivery, and Intracardiac Echocardiography for valve evaluation after implantation. Radiation metrics, procedural time, and clinical outcomes were compared between groups. When the traditional protocol group was compared with the multimodality protocol group, a significant reduction was described for total fluoroscopy time (31.6 min vs. 26.2 min), dose of contrast per kilogram (1.8 mL/Kg vs. 0.9 mL/Kg), DAP/kg (26.6 µGy·m2/kg vs. 19.9 µGy·m2/kg), and Air Kerma (194 mGy vs. 99.9 mGy). A reduction for procedure time was noted (140 min vs. 116.5 min), but this was not statistically significant. There was no difference in clinical outcomes or the presence of complications between groups. The combination of novel technology in PPVI caused a significant reduction in radiation metrics without increasing the complication rate in our population.

Surgically placed radiopaque markers: Proof-of-concept of a novel technique to facilitate percutaneous interventions in neonates and infants.

OBJECTIVES: Aim of this study was to evaluate feasibility and benefit of self-designed, radiopaque markers as a novel technique in neonates and infants with shunt- or duct-dependent lesions. BACKGROUND: Surgically placed radiopaque markers have the potential to facilitate postoperative percutaneous interventions. METHODS: All consecutive children with surgically placed radiopaque markers involving systemic-to-pulmonary artery connections or arterial ducts in the context of hybrid palliation and subsequent cardiac catheterization between January 2013 and March 2019 were included in this analysis. Our primary endpoint was our concept's feasibility, which we defined as a combination of surgical feasibility and the percutaneous intervention's success. Secondary endpoint was the rate of complications resulting from the surgical procedure or during catheterization. RESULTS: Radiopaque markers that reveal the proximal entry of a surgical shunt or the arterial duct proved to be a feasible and beneficial approach in 25 postoperative catheterizations. The markers' high accuracy enabled easy probing and proper stent positioning in 13 neonates with a median age and weight of 121 days (range 9-356) and 4.7 kg (1.6-9.4) at the intervention. No procedural complications or unanticipated events associated with the radiopaque marker occurred. The markers were never lost, never migrated, and caused no local obstructive lesion. Surgical removal was straightforward in all patients. CONCLUSIONS: Radiopaque markers are a promising and refined technique to substantially facilitate target vessel access and enabling the accurate positioning of stents during postoperative percutaneous procedures.

Procedural, pregnancy, and short-term outcomes after fetal aortic valvuloplasty.

OBJECTIVES: We aimed to evaluate the effect of technical aspects of fetal aortic valvuloplasty (FAV) on procedural risks and pregnancy outcomes. BACKGROUND: FAV is performed in cases of severe mid-gestation aortic stenosis with the goal of preventing hypoplastic left heart syndrome (HLHS). METHODS: The International Fetal Cardiac Intervention Registry was queried for fetuses who underwent FAV from 2002 to 2018, excluding one high-volume center. RESULTS: The 108 fetuses had an attempted cardiac puncture (mean gestational age [GA] 26.1 ± 3.3 weeks). 83.3% of attempted interventions were technically successful (increased forward flow/new aortic insufficiency). The interventional cannula was larger than 19 g in 70.4%. More than one cardiac puncture was performed in 25.0%. Intraprocedural complications occurred in 48.1%, including bradycardia (34.1%), pericardial (22.2%) or pleural effusion (2.7%) requiring drainage, and balloon rupture (5.6%). Death within 48 hr occurred in 16.7% of fetuses. Of the 81 patients born alive, 59 were discharged home, 34 of whom had biventricular circulation. More than one cardiac puncture was associated with higher complication rates (p < .001). Larger cannula size was associated with higher pericardial effusion rates (p = .044). On multivariate analysis, technical success (odds ratio [OR] = 10.9, 95% confidence interval [CI] = 2.2-53.5, p = .003) and later GA at intervention (OR = 1.5, 95% CI = 1.2-1.9, p = .002) were associated with increased odds of live birth. CONCLUSIONS: FAV is an often successful but high-risk procedure. Multiple cardiac punctures are associated with increased complication and fetal mortality rates. Later GA at intervention and technical success were independently associated with increased odds of live birth. However, performing the procedure later in gestation may miss the window to prevent progression to HLHS.

Percutaneous Impella RP use for refractory right heart failure in adolescents and young adults-A multicenter U.S. experience.

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.

Transcatheter treatment of acquired coronary sinus ostium atresia in a child with complex congenital heart disease.

Congenital coronary sinus ostium atresia is a rare condition that is typically considered benign, as long as there is adequate drainage via another route. However, in children with single ventricle congenital heart disease, adequate drainage may not be assured after complex surgical interventions, putting them at risk for myocardial injury. We present a patient with complex single ventricle congenital heart disease who developed acquired coronary sinus ostium atresia after surgical intervention that was treated by a transcatheter approach to prevent the sequelae of coronary sinus hypertension.