Cardiorespiratory Instability after Percutaneous Patent Ductus Arteriosus Closure: A Multicenter Cohort Study.

OBJECTIVE: To evaluate postprocedural clinical characteristics of preterm infants undergoing transcatheter patent ductus arteriosus (PDA) closure, including oxygenation/ventilation failure and cardiovascular compromise. STUDY DESIGN: Multicenter retrospective cohort study of preterm infants who were ≤2 kg at the time of percutaneous PDA closure between August 2018 and July 2021. Indices of cardiorespiratory stability were collected pre-closure, immediately post-closure, and subsequently averaged every 4 hours for the first 24 hours post-procedure. The primary outcome was incidence of post-transcatheter cardiorespiratory syndrome: composite of hemodynamic instability (defined by systemic hypotension, systemic hypertension, or use of new inotropes/vasopressors in the first 24 hours after catheterization) and at least one of the following: (i) ventilation failure or (ii) oxygenation failure. RESULTS: A total of 197 patients were included with a median [IQR] age and weight at catheterization of 34 [25, 43] days and 1090 [900, 1367] grams, respectively. The primary composite outcome of post-transcatheter cardiorespiratory syndrome was reported in 46 (23.3%). CONCLUSION: Post-transcatheter cardiorespiratory syndrome is characterized primarily by systemic hypertension and oxygenation failure, with a very low incidence of hypotension and need for inotropes.

Strategies and techniques for percutaneous Veno-Arterial ECMO cannulation and decannulation in children.

OBJECTIVES: To describe the techniques used for percutaneous veno-arterial extracorporeal membrane oxygenation (VA-ECMO) cannulation and decannulation in children with the pediatric interventional cardiologist (PIC) as the primary operator, and present outcomes of this initial clinical experience. BACKGROUND: Percutaneous VA-ECMO during cardiopulmonary resuscitation (CPR) has been successfully performed in adults, but currently, not much data exists on children. METHODS: This is a single-center study including VA-ECMO cannulations performed by the PIC between 2019 and 2021. Efficacy was defined as the successful initiation of VA-ECMO without surgical cutdown. Safety was defined as the absence of additional procedures related to cannulation. RESULTS: Twenty-three percutaneous VA-ECMO cannulations were performed by PIC on 20 children with 100% success. Fourteen (61%) were performed during ongoing CPR, and nine for cardiogenic shock. The Median age was 15 (0.15-18) years, and the median weight was 65 (3.3-180) kg. All arterial cannulations were via the femoral artery except in one, 8-week-old infant who was cannulated in the carotid artery. A distal perfusion cannula was placed in the ipsilateral limb in 17 (78%). The median time from initiating cannulation to ECMO flow was 35 (13-112) minutes. Two patients required arterial graft placement at the time of decannulation and one needed below-knee amputation. ECMO support was maintained for a median of 4 (0.3-38) days. Thirty-day survival was 74%. CONCLUSION: Percutaneous VA-ECMO cannulations can be effectively performed, even during CPR with the Pediatric Interventional Cardiologist being the primary operator. This is an initial clinical experience. Future outcome studies compared with standard surgical cannulations are necessary to advocate routine percutaneous VA-ECMO in children.

Safety and Short-Term Outcomes for Infants < 2.5 kg Undergoing PDA Device Closure: A C3PO Registry Study.

To evaluate short-term procedural outcomes and safety for infants < 2.5 kg who underwent catheterization with intended patent ductus arteriosus (PDA) device closure in a multi-center registry, as performance of this procedure becomes widespread. A multi-center retrospective review was performed using data from the Congenital Cardiac Catheterization Project on Outcomes (C3PO) registry. Data were collected for all intended cases of PDA closure in infants < 2.5 kg from April 2019 to December 2020 at 13 participating sites. Successful device closure was defined as device placement at the conclusion of the catheterization. Procedural outcomes and adverse events (AE) were described, and associations between patient characteristics, procedural outcomes and AEs were analyzed. During the study period, 300 cases were performed with a median weight of 1.0 kg (range 0.7-2.4). Successful device closure was achieved in 98.7% of cases with a 1.7% incidence of level 4/5 AEs, including one periprocedural mortality. Neither failed device placement nor adverse events were significantly associated with patient age, weight or institutional volume. Higher incidence of adverse events associated with patients who had non-cardiac problems (p = 0.017) and cases with multiple devices attempted (p = 0.064). Transcatheter PDA closure in small infants can be performed with excellent short-term outcomes and safety across institutions with variable case volume.

Use of the Medtronic Microvascular Plug 7Q for transcatheter closure of large patent ductus arteriosus in infants weighing less than 2.5 kg.

BACKGROUND: The sole Food and Drug Administration-approved device for transcatheter closure of the patent arterial duct in premature infants is indicated for patent ductus arteriosus (PDAs) ≤ 4 mm in diameter. We report a two-center experience with transcatheter closure of large PDAs (>4 mm) in infants weighing <2.5 kg using the Microvascular Plug 7Q (MVP-7Q) device. METHODS: This is a retrospective review of departmental databases and medical charts to define patient cohort and report demographic, procedural, and follow-up data. RESULTS: Twenty-two patients (12 male) with a median gestational age and birthweight of 25.5 weeks (interquartile range [IQR] = 24-28) and 800 g (572-1075), respectively, underwent attempted PDA occlusion with the MVP-7Q using a transvenous approach. The median age and weight at the time of PDA occlusion was 32 days (IQR = 24-28) and 1100 g (IQR = 960-1700), respectively. The median PDA length was 12 mm (IQR = 11-12.65). The median PDA diameters at the aortic and pulmonary ends were 5.1 (IQR = 4.9-5.5) and 4.8 mm (IQR = 4.6-5.3), respectively. Successful device occlusion was achieved in 20 patients (91%). There were two failed attempts: One due to inappropriate sizing, and the other secondary to left pulmonary artery stenosis. There were no procedural complications and no residual shunting on follow-up. CONCLUSIONS: The MVP-7Q is safe and effective for transcatheter closure of large (>4 mm) PDAs in infants <2.5 kg. The lack of retention disks may help with avoiding impingement on surrounding vessels.

Percutaneous Closure of Patent Ductus Arteriosus in Infants 1.5 kg or Less: A Meta-Analysis.

OBJECTIVE: To investigate technical success and safety of percutaneous patent ductus arteriosus closure in infants ≤1.5 kg. STUDY DESIGN: A systematic review and meta-analysis was performed. Data sources included Scopus, Web of Science, Embase, CINAHL, Cochrane, and PubMed from inception to April 2020. Publications were included if they had a clear definition of the intervention as percutaneous patent ductus arteriosus closure in infants ≤1.5 kg. Data extraction was independently performed by multiple observers. Primary outcome was technical success and secondary outcomes were adverse events (AEs). Subgroup analysis was performed in infants ≤6.0 kg. Data were pooled by using a random-effects model. RESULTS: We included 28 studies, including 373 infants ≤1.5 kg and 69 studies enrolling 1794 infants ≤6.0 kg. In patients ≤1.5 kg, technical success was 96% (95% CI, 93%-98%; P = .16; I2 = 23%). The overall incidence of AE was 27% (95% CI, 17%-38%; P < .001; I2 = 70%) and major AEs was 8% (95% CI, 5%-10%; P = .63; I2 = 0%). There were 5 deaths related to the procedure (2%; 95% CI, 1%-4%; P = .99; I2 = 0%); 4 of these deaths occurred in infants <0.8 kg. The probability of technical failure was inversely related to age at the time of the procedure (OR, 0.9; 95% CI, 0.830-0.974; P = .009). Weight at intervention has decreased over time and procedural success has increased. CONCLUSIONS: Percutaneous patent ductus arteriosus closure is feasible in infants ≤1.5 kg with few major AEs. The procedural success rate is high, despite performing the intervention in smaller patients. PROSPERO REGISTRATION: CRD42020145230.

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.

Hot topics in interventional cardiology: Proceedings from the society for cardiovascular angiography and interventions (SCAI) 2021 think tank.

The Society for Cardiovascular Angiography and Interventions (SCAI) Think Tank is a collaborative venture that brings together interventional cardiologists, administrative partners, and select members of the cardiovascular industry community annually for high-level field-wide discussions. The 2021 Think Tank was organized into four parallel sessions reflective of the field of interventional cardiology: (a) coronary intervention, (b) endovascular medicine, (c) structural heart disease, and (d) congenital heart disease. Each session was moderated by a senior content expert and co-moderated by a member of SCAI's Emerging Leader Mentorship program. This document presents the proceedings to the wider cardiovascular community in order to enhance participation in this discussion, create additional dialog from a broader base, and thereby aid SCAI, the industry community and external stakeholders in developing specific action items to move these areas forward.

Consensus Guidelines for the Prevention and Management of Periprocedural Complications of Transcatheter Patent Ductus Arteriosus Closure with the Amplatzer Piccolo Occluder in Extremely Low Birth Weight Infants.

Transcatheter closure of patent ductus arteriosus (PDA) in premature infants is a feasible, safe, and an effective alternative to surgical ligation and may be performed with an implant success rate of 97%. Major procedural complications related to transcatheter PDA closure in extremely low birth weight (ELBW) infants are relatively infrequent (< 3%) ,but may be associated with a fatality if not optimally managed. Operators performing transcatheter PDA closures should be knowledgeable about these potential complications and management options. Prompt recognition and treatment are often necessary to avoid serious consequences. With strict guidelines on operator training, proctoring requirements, and technical refinements, transcatheter PDA closure in ELBW infants can be performed safely with low complication rates. This article summarizes the consensus guidelines put forward by a panel of physicians for the prevention and management of periprocedural complications of transcatheter PDA closure with the Amplatzer Piccolo Occluder in ELBW infants.

Amplatzer Piccolo Occluder clinical trial for percutaneous closure of the patent ductus arteriosus in patients ≥700 grams.

OBJECTIVES: Characterize the safety and effectiveness of the Amplatzer Piccolo Occluder for patent ductus arteriosus (PDA) closure. BACKGROUND: The presence of a hemodynamically significant PDA has been associated with an increased risk of morbidity and mortality in children born premature. METHODS: This was a single arm, prospective, multicenter, non-randomized study to evaluate the Amplatzer Piccolo Occluder to treat PDA in patients ≥700 g. From June 2017 to February 2019, 200 patients were enrolled at nine centers, with 100 patients weighing ≤2 kg. Primary effectiveness endpoint was the rate of PDA closure at 6-month follow-up. Primary safety endpoint was the rate of major complications through 6 months. Secondary endpoint was rate of significant pulmonary or aortic obstruction through 6 months' follow-up. RESULTS: The implant success rate was 95.5% (191/200) overall and 99% in patients ≤2 kg (99/100). The primary effectiveness endpoint was achieved in 99.4% of implanted patients. Four patients experienced a primary safety endpoint event (2 transfusions, 1 hemolysis, and 1 aortic obstruction). There were no branch pulmonary artery obstructions. Five patients, all ≤2 kg, were noted to have worsening of tricuspid regurgitation (TR) after the procedure. None of the TR incidences manifested clinically. The Amplatzer Piccolo Occluder received FDA approval in January 2019 and became the first device approved for PDA closure in patients ≥700 g. CONCLUSIONS: This study supports the safety and effectiveness of the Amplatzer Piccolo Occluder, particularly in patients between 700 g and 2 kg where there is currently a significant unmet need in the United States. ClinicalTrials.gov identifier: NCT03055858.

Accessing Femoral Arteries Less than 3 mm in Diameter is Associated with Increased Incidence of Loss of Pulse Following Cardiac Catheterization in Infants.

To evaluate whether avoidance of a risk factor associated with loss of pulse (LOP) following femoral artery (FA) catheterization in infants identified from previous study, was associated with decreased incidence of LOP during a prospective evaluation. Since initiation of routine ultrasound guided femoral arterial access (UGFAA) for infants undergoing catheterization in Jan 2003-Dec 2011 (Period-1), our incidence of LOP had stayed steady. Prospective evaluation between Jan 2012-Dec 2014 (Period-2), identified FA-diameter < 3 mm as risk factor for LOP. Between Jan 2015-Dec 2018 (Period-3), an initiative to avoid UGFAA for FA-diameter < 3 mm was implemented to determine whether that led to a decreased incidence of LOP. FA-diameter was measured prior to USGFAA and ratio of outer diameter of arterial sheath to luminal diameter of cannulated artery (OD/AD ratio) was calculated during Periods-2 and 3. The incidence and risk factors for LOP were assessed during the three periods. FA-access rates dropped significantly during Period-3 (56.7% vs. 93.8% and 90.4% during Periods-1 and 2, respectively, p < 0.001). Incidence of LOP in Period-3 decreased to 2.7% compared to 12.5% (Period-1) and 17.4% (Period-2) (p < 0.001). By multivariate analysis, FA size < 3 mm and an OD/AD ratio > 40% were the only significant independent predictors for LOP (OR 6.48, 95% CI 2.3-11.42, p < 0.001 and OR 4.16, 95% CI 1.79-8.65, p < 0.01, respectively). Access of femoral artery < 3 mm and OD/AD ratio > 50% are associated with increased incidence of LOP. Avoidance of these factors may help decrease complications in infants undergoing cardiac catheterizations.

Construction of Femoral Vessel Nomograms for Planning Cardiac Interventional Procedures in Children 0-4 Years Old.

The objectives of this study were to construct femoral artery (FA) and femoral vein (FV) nomograms in children aged 0-4 years and to construct probability curves for the occurrence of arterial access complications based on the size of the FA. The FV and FA are commonly accessed during cardiac catheterizations in children with congenital heart diseases (CHD). However, nomograms for vessel dimensions based on child's age or size are not available. This knowledge may be helpful for interventional planning. A prospective study was performed on 400 children (age 0-4 years) with CHD undergoing cardiac catheterizations over a 3-year period. Ultrasound evaluation of the right and left FA and FV was performed under anesthesia prior to vascular access. Regression modeling was applied to derive nomograms based on quantile polynomial regression, which yielded good fit to the data judged by R-squared. GAMLSS transformation method was used to formulate smoothed percentiles. A separate prospective evaluation of FA to determine the size below which loss of pulse (LOP) are likely to occur was performed. Nomograms for FA and FV diameter and cross-sectional area against age and body surface area and probability curves for FA LOP were constructed. It is now possible to examine ultrasound-based normal sizes of femoral vein and artery in children 0-4 years of age. Femoral vessel nomograms and LOP probability curves may help with interventional planning. Future studies with larger sample size, including children of other ages may be useful.

Role of Transcatheter patent ductus arteriosus closure in extremely low birth weight infants.

BACKGROUND: Patent ductus arteriosus (PDA) is common in extremely low birth weight (ELBW) infants. The objectives of this study were to describe our early clinical experience of transcatheter PDA closure (TCPC) in ELBW infants, compare outcomes with surgical ligation of PDA (SLP), and identify risk factors for prolonged respiratory support. METHODS: A retrospective review was performed comparing infants born <27 weeks, weighing <1 kg at birth and < 2 kg during TCPC with 2:1 propensity-score matched group of infants that underwent SLP. Change in respiratory severity scores (RSS) immediately post-procedure and the time taken for return to pre-procedure RSS for TCPC versus SLP was compared. Factors contributing to prolonged elevation of RSS were identified. RESULTS: Eighty ELBW infants (median procedure weight: 1060 [range 640-2000] grams) that underwent successful TCPC were compared with 40 infants that underwent SLP (procedure weight 650-1760 g). There was greater increase in RSS following SLP compared to TCPC (76% vs. 18%; P < 0.01). It took longer for RSS to return to pre-procedural scores post-SLP compared to post-TCPC (28 vs. 8.4 hr; P < 0.01). Elevated pulmonary artery pressure (PAP) and TCPC at >8 weeks of age were associated with prolonged (>30-days) elevation of RSS ≥ 1 (OR = 5.4, 95%CI: 2.2-9.4, P < 0.01 and OR = 2.86, 95%CI: 1.5-4.2, P = 0.05 respectively). Overall complication rate for TCPC was 3.7%. CONCLUSIONS: TCPC is feasible in infants as small as 640-2000 g and can be performed safely in the majority. TCPC may offer faster weaning of respiratory support compared to SLP when performed earlier in life, and before the onset of elevated PAP.

Utility of the Medtronic microvascular plug™ as a transcatheter implantable and explantable pulmonary artery flow restrictor in a swine model.

BACKGROUND: A surgical pulmonary artery band (PAB) is used to control excessive pulmonary blood flow for certain congenital heart diseases. Previous attempts have been made to develop a transcatheter, implantable pulmonary flow restrictor (PFR) without great success. We modified a microvascular plug (MVP) to be used as a PFR. The objectives of this study were to demonstrate feasibility of transcatheter implantation and retrieval of the modified MVP as a PFR, and compare PA growth while using the PFR versus PAB. METHODS AND RESULTS: The PFR was implanted in eight newborn piglets in bilateral branch pulmonary arteries (PAs). Immediately post-PFR implantation, the right ventricular systolic pressure increased from a median of 20-51 mmHg. Transcatheter retrieval of PFR was 100% successful at 3, 6, and 9 weeks and 50% at 12-weeks post-implant. A left PAB was placed via thoracotomy in four other newborn piglets. Debanding was performed 6-weeks later via balloon angioplasty. On follow-up, the proximal left PA diameters in the PFR and the PAB groups were similar (median 8 vs. 7.1 mm; p = 0.11); albeit the surgical band sites required repeat balloon angioplasty secondary to recurrent stenosis. By histopathology, there was grade II vessel injury in two pigs immediately post-retrieval of PFR that healed by 12 weeks. CONCLUSIONS: Transcatheter implantation and retrieval of the MVP as a PFR is feasible. PA growth is comparable to surgical PAB, which is likely to require reinterventions. The use of the MVP as a PFR in humans has to be trialed before recommending its routine use.

Variability in radiation dose and image quality: A comparison across fluoroscopy-system vendors, generations of equipment and institutions.

OBJECTIVES: To evaluate differences in radiation dose and image quality across institutions, fluoroscope vendors and generations of fluoroscopes for pediatric cardiac catheterization. BACKGROUND: Increased recognition of the potentially harmful effects of ionizing radiation has spurred technological advances in fluoroscopes, as well as increased focus on optimizing fluoroscope performance. There is currently little understanding of variability in the dose-image quality relationship across institutions, fluoroscope vendor and/or generation of equipment. METHODS: We evaluated latest generation fluoroscopes from Phillips, Siemens, GE, and Toshiba, and an older generation Phillips fluoroscope (release date 2003) at three different institutions. Radiation dose was measured using an anthropomorphic dose-assessment phantom with effective dose in mSv estimated from Monte Carlo simulations. Image quality phantom images were scored on a 12-point scale by three blinded reviewers. RESULTS: Fluoroscope effective doses ranged from 0.04 to 0.14 mSv/1,000 pulses for fluoroscopy with associated composite image quality scores ranging from 8.0 ± 0.6 to 10.4 ± 1.3. For cineangiography, effective doses ranged from 0.17 to 0.57 mSv/1,000 frames with image quality scores ranging from 10.1 ± 0.3 to 11.1 ± 0.3. There was modest correlation between effective dose and image quality (r = 0.67, P = 0.006). The older generation fluoroscope delivered consistently higher doses than the newer generation systems (2.3- to 3.5-fold higher for fluoroscopy; 1.1- to 3.4-fold higher for cineangiography) without appreciable differences in image quality. CONCLUSION: Technological advances have markedly improved fluoroscope performance. Comparing latest generation systems across vendors and institutions, we found variability in the dose-IQ relationship and speculate that this reflects both equipment and institutional optimization practices.

Femoral vein homograft as Sano shunt results in improved pulmonary artery growth after Norwood operation.

OBJECTIVE: To evaluate differences in interstage growth of pulmonary arteries between use of polytetrafluoroethylene and femoral vein homograft as Sano shunt during stage-I Norwood palliation. METHODS: A retrospective review of all patients who survived to the second stage following Norwood-Sano operation at two institutions was performed. Either polytetrafluoroethylene or the valved segment of femoral vein homograft was used for construction of the Sano shunt. The size of pulmonary arteries was compared at pre-Glenn catheterisation. RESULTS: A total of 48 neonates with the diagnosis of hypoplastic left heart syndrome or its variants comprised the study population. Femoral vein homograft of 5-6 mm diameter was used in 14 and polytetrafluoroethylene graft of 5 mm was used in 34 patients. The two groups were comparable in terms of preoperative demographics and age at time of pre-Glenn catheterisation (3.9±0.7 versus 3.4±0.8 months, p=0.06). Patients who received femoral vein homograft demonstrated a significantly higher pre-Glenn Nakata index [264 (130-460) versus 165 (108-234) mm2/m2, p=0.004]. The individual branch pulmonary arteries were significantly larger in the femoral vein group (right, 7.8±3.6 versus 5.0±1.2, p=0.014; left, 7.2±2.1 versus 5.6±1.9, p=0.02). There were no differences in cardiac index, Qp:Qs, ventricular end-diastolic pressure or systemic oxygen saturations. CONCLUSIONS: Utilisation of a valved segment of femoral vein homograft as right ventricle to pulmonary artery conduit during Norwood-Sano operation confers better interstage growth of the pulmonary arteries. Further studies are needed to evaluate the impact of femoral vein homograft on single ventricle function.

Abstract 12670: Variability in Radiation Dose and Image Quality: A Comparison Across Fluoroscopy-system Vendors and Generations of Equipment.

INTRODUCTION: Increased recognition of the potentially harmful effects of ionizing radiation has spurred technological advances to reduce exposure during fluoroscopy. However there is currently little understanding of the dose-image quality (IQ) relationship between fluoroscopy vendors and across generations of equipment used for imaging during pediatric catheterization. METHODS: We evaluated latest generation fluoroscopy systems from Phillips, Siemens, GE and Toshiba, and an older generation Phillips system (2004 release). Fluoroscopy and cineangiography were performed on a tissue simulation anthropomorphic phantom using a standardized imaging approach. Phantom surface exposures were used for Monte Carlo simulations to calculate radiation effective dose, accounting for differences in beam parameters. We also imaged a fluoroscopy IQ phantom to assess contrast-detail and line-per-inch visualization. IQ images were scored by 3 blinded reviewers with scores averaged to produce a composite rating (scale 0-18). To assess the impact of imaging approach we then simulated a neonatal cardiac catheterization incorporating "typical" imaging protocols provided by institutions using the various systems. RESULTS: Effective doses and IQ scores are summarized in the table. Effective doses varied by >400% with the older generation system consistently delivering markedly higher doses. The associated figure summarizes dose and IQ for a simulated neonatal cardiac catheterization which accounts for measured doses as well as the reported institutional imaging parameters summarized in the figure legend. CONCLUSION: These data demonstrate substantial technological improvements in fluoroscopy equipment and may be useful to justify institutional "upgrades". Comparing latest generation systems across vendors and institutions, we found variability in the dose-IQ relationship that reflects both equipment and imaging approach.

Initial clinical experience with the Medtronic Micro Vascular Plug™ in transcatheter occlusion of PDAs in extremely premature infants.

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.

Use of 3-D digital subtraction rotational angiography during cardiac catheterization of infants and adults with congenital heart diseases.

OBJECTIVE: To compare image quality, radiation and contrast doses required to obtain 3D-Digital subtraction rotational angiography (3D-DSRA) with 3D-Digital rotational angiography (3D-DRA) in infants (children ≤ 2 years of age) and adults with congenital heart diseases (ACHD). BACKGROUND: 3D-DRA can be performed with radiation doses comparable to bi-plane cine-angiography. However, 3D-DRA in infants requires a large contrast volume. The resolution of 3D-DRA performed in ACHD patients is limited by their soft tissue density. We hypothesized that the use of 3D-DSRA could help alleviate these concerns. METHODS: Radiation (DAP) and contrast doses required to obtain 3D-DSRA was compared with 3D-DRA in 15 age-, size-, and intervention-matched infants and 15 ACHD patients. The diagnostic quality and utility of these two modalities were scored by 4 qualified independent observers. RESULTS: Both in infants and adults, the median contrast volume for 3D-DSRA was lower than 3D-DRA (0.98 vs. 1.81 mL/kg; P < 0.001 and 0.92 vs. 1.4 mL/kg; P < 0.001, respectively) with an increased DAP (median: 188 vs. 128 cGy cm2 ; P = 0.068 and 659 vs. 427 cGy cm2 ; P = 0.045, respectively). The diagnostic quality and utility scores for rotational-angiography, and 3D-reconstruction were superior for 3D-DSRA (score = 94 vs. 80%, P = 0.03 and 90 vs.79%, P = 0.01, respectively) and equivalent for multi-planar-reformation and 3D-roadmapping in ACHD patients compared with 3D-DRA. All scores for both modalities were equivalent for infants. CONCLUSIONS: 3D-DSRA can be acquired using lower contrast volume with a mildly higher radiation dose than 3D-DRA in infants and ACHD patients. The diagnostic quality and utility scores for 3D-DSRA were higher in ACHD patients and equivalent for infants compared with 3D-DRA.

Acute and mid-term outcomes of stent implantation for recurrent coarctation of the aorta between the Norwood operation and fontan completion: A multi-center Pediatric Interventional Cardiology Early Career Society Investigation.

OBJECTIVES: We sought to evaluate outcomes of stent implantation (SI) for recurrent coarctation of the aorta (RC) following the Norwood operation. BACKGROUND: RC is common following the Norwood operation. Balloon angioplasty (BA) is standard treatment but may result in unsatisfactory relief of RC. SI may improve RC, but outcome data are limited. METHODS: We performed a multi-center retrospective study of patients who underwent SI for RC between the Norwood operation and Fontan completion. Outcomes were examined, including procedural success, serious adverse events (SAE), and freedom from re-intervention. A core laboratory was utilized to review angiograms. Coarctation Index (CI) was calculated before and after SI. Paired t-test and Wilcoxon signed-rank test were used to compare pre- and post-SI variables. RESULTS: Thirty-three patients at 8 centers underwent SI for RC at a median age of 5 months (IQR 4.1, 13.3) and weight of 5.9 kg (5.2, 8.6). Aortic arch gradient improved from 20 (15, 24) to 0 (0, 2) mmHg following SI (P < 0.0001). The median CI improved from 0.54 (0.43, 0.62) to 0.97 (0.89, 1.06) following SI (P < 0.0001). There were no procedural deaths but SAEs occurred in 12 (36%) patients. During a median follow-up duration of 29.7 months (6.8, 48.0), freedom from death or heart transplant was 82%, and from re-intervention was 45%, with median time to re-intervention of 20.1 months (11.4, 40.3). CONCLUSIONS: SI for treatment of RC in patients after the Norwood operation provides excellent acute relief of obstruction. Intraprocedural hemodynamic instability is common and re-intervention is frequent at mid-term follow-up.

Clinical evaluation of a radio-protective cream for the hands of the pediatric interventional cardiologist.

OBJECTIVES: The aim of this study was to evaluate the effectiveness of UltraBLOX™ radiation attenuating hand cream during lengthy cardiac catheterization procedures in children. BACKGROUND: The hands of interventional cardiologists receive high doses of radiation due to their proximity to the X-ray beam. Radiation attenuating gloves have about a 26% attenuation rate, but reduce dexterity and tactile sensation. The UltraBLOX™ cream is a new FDA-approved X-ray attenuating cream that can be applied to the operator's hands for radio-protection. METHODS: Two nanoDot™ dosimeters were secured side by side on the dorsum of the operator's (n = 2) left hand close to the wrist. One dosimeter and the rest of the hand were covered with 0.2 mm layer of the cream. The other dosimeter was unshielded. Procedures were performed using 110 kVp fluoroscopy at 15 pulses/sec. The measurements were categorized into four groups dependent on the duration of the procedure. The patients in all four groups were well matched for age and size. RESULTS: Procedural and cumulative hand radiation doses were higher with longer procedural duration. The overall % attenuation by the cream was 39.7% (28.6-51.5) and was unaffected by the length of the procedure (median: 40.9% at 30 min and 41.4% at 180 min; P = 0.66) or the dose of radiation. The kappa statistic for interobserver agreement for good tactile sensitivity was 0.82. CONCLUSIONS: UltraBLOX™ cream provides a new option for radio-protection for the hands of interventional cardiologists without impairing tactile sensitivity. There was no decrease in attenuation up to 180 min. © 2016 Wiley Periodicals, Inc.