Marked lateral ST-segment elevation with inferior ST-segment depression in an asymptomatic 12 year-old girl: A normal variant?

Significant ST-segment changes raise concern for myocardial ischemia, cardiomyopathy or myocardial inflammation and therefore, warrant an extensive and often invasive cardiovascular evaluation. We report a 12 year-old asymptomatic African-American girl with marked ST-segment elevation in leads I and aVL and ST-segment depression in inferior leads II, III and aVF. Extensive cardiovascular evaluation did not reveal any abnormality suggesting that these findings, which have previously not been reported, are likely benign, at least in this young girl.

Serial Versus Direct Dilation of Small Diameter Stents Results in a More Predictable and Complete Intentional Transcatheter Stent Fracture: A PICES Bench Testing Study.

Balloon-expandable stents, implanted in infants and children with congenital heart disease (CHD), often require redilation to match somatic growth. Small diameter stents may eventually require longitudinal surgical transection to prevent iatrogenic vascular stenosis. Intentional transcatheter stent fracture (TSF) is an emerging alternative approach to stent transection, but little is known about the optimal stent substrate and best protocol to improve the likelihood of successful TSF. Bench testing was performed with a stent dilation protocol. After recording baseline characteristics, stents were serially or directly dilated using ultra-high-pressure balloons (UHPB) until fracture occurred or further stent dilation was not possible. Stent characteristics recorded were as follows: cell design, metallurgy, mechanism, and uniformity of fracture. Stents tested included bare-metal coronary stents, premounted small diameter stents, and ePTFE-covered small diameter premounted stents. Ninety-four stents representing 9 distinct models were maximally dilated, with 80 (85%) demonstrating evidence of fracture. Comprehensive fracture details were recorded in 64 stents: linear and complete in 34/64 stents (53.1%), linear and incomplete in 9/64 stents (14.1%), transverse/complex and complete in 6/64 stents (9.4%), and transverse/complex and incomplete in 15/64 stents (23.4%). Stent fracture was not accomplished in some stent models secondary to significant shortening, i.e., "napkin-ring" formation. Serial dilation resulted in evidence of fracture in 62/67 (92.5%) stents compared with 18/27 (66.7%) stents in the direct dilation group (p = 0.003). Intentional TSF is feasible in an ex vivo model. Serial dilation more reliably expanded the stent and allowed for ultimate stent fracture, whereas direct large diameter dilation of stents was more likely to generate a "napkin-ring" configuration, which may be more resistant to fracture. In vivo animal and human testing is necessary to better understand the response to attempted TSF for newly developed stents as well as those currently in use.

Transcatheter closure of patent ductus arteriosus using the AMPLATZER™ duct occluder II (ADO II).

OBJECTIVES: The study purpose is to evaluate the safety and efficacy of the ADO II device for closure of patent ductus arteriosus (PDA) in children. BACKGROUND: Transcatheter treatment of PDA has been evolving for 40+ years and is the treatment of choice. The AMPLATZER™ Duct Occluder (ADO) device was developed for larger diameter ducts and is not ideal in all PDAs. ADO II was developed for small to moderate-sized ducts. METHODS: This is a single-arm, multicenter study evaluating safety and efficacy of the ADO II device. Patients <18 years were screened for a PDA ≤5.5 mm in diameter and 3-12 mm in length. Right and left heart catheterization was performed, and hemodynamic data were obtained at the time of implant. The diameter of the left pulmonary artery (LPA) and descending aorta, and the presence of any pre-existing pressure gradients across the LPA or aortic arch were assessed at baseline and 6 months post-implant. RESULTS: A total of 192 patients were enrolled. The median implant time was 74 min. Median fluoroscopy time was 12 min. A retrograde (aortic) approach was used in 33% of procedures and demonstrated a statistically significant reduction in fluoroscopy time (P value = 0.0018) compared to an antegrade approach. The device was successfully implanted in 93% of patients, with complete closure in 98% of successful implantations. CONCLUSIONS: In this prospective study, the ADO II was safe and effective for closure of small to moderate PDAs. Implantation is simple and the ability for retrograde aortic delivery reduces procedure-related radiation exposure. © 2017 Wiley Periodicals, Inc.

Expansion Characteristics of Stents Used in Congenital Heart Disease: Serial Dilation Offers Improved Expansion Potential Compared to Direct Dilation: Results from a Pediatric Interventional Cardiology Early Career Society (PICES) Investigation.

OBJECTIVE: Intravascular stents are now routinely used to treat young patients with vascular stenoses. Future stent redilations are often necessary to account for somatic growth. The purpose of this study was to compile a database of characteristics for stents commonly used in the treatment of congenital heart disease patients, and compare serial dilation to direct dilation to the maximal diameter. DESIGN: A standardized bench testing protocol was established and utilized in the assessment of all stents. Ultra high pressure balloons were used to serially dilate each stent by set increments until the stent reached at least 24 mm in diameter, developed a napkin-ring configuration, or fractured. Length and diameter of each stent were measured at baseline and following each stage of dilation. Maximal stent diameters, foreshortening properties, and ability to fracture were reported. Stents were then tested for direct dilation from the primary diameter to the maximal diameter, and the same data was obtained. RESULTS: A total of 127 stents were bench-tested, 80 of which were serially dilated and 47 directly dilated. Most premounted stents could be serially dilated to approximately twice their stated nominal diameter. All tested unmounted stents could be serially dilated to ≥20 mm. Foreshortening occurred at larger diameters, but varied significantly among different stent types. Serial dilation offered more consistent results with significantly less foreshortening and more symmetric expansion when compared with direct dilation. Most premounted stents could be fractured when serially dilated. CONCLUSIONS: All tested vascular stents can be dilated beyond their nominal implantation diameter. Serial dilation offers a much more reliable response with uniform expansion, less foreshortening, greater maximal diameter, and improved intentional fracture potential, as compared to direct dilation from the nominal to maximal diameter. In vivo studies are necessary to corroborate these findings in the congenital heart disease population.

Stent placement for palliation of cor triatriatum dexter in a dog with suspected patent foramen ovale.

An 11 month old spayed, female dog presented with exercise intolerance and cyanosis upon exertion. Echocardiography revealed an imperforate cor triatriatum dexter with mild tricuspid valve dysplasia, an underfilled right ventricle and significant right to left shunting across a presumptive patent foramen ovale. Balloon dilation of the abnormal atrial membrane was initially successful in creating a communication between the right atrial chambers, but stenosis of the original perforation and persistent clinical signs prompted a second intervention. A balloon expandable biliary stent was placed across the abnormal partition, improving caudal venous return to the right ventricle and reducing the right to left shunt. Three months after stent placement, resting oxygen saturation had normalized. Six months after stent placement, exercise tolerance had improved and exertional cyanosis had resolved. Long term follow up will be necessary to assess for remodeling of the right ventricle with improved venous return. Stent placement can be considered as a palliative treatment option for cor triatriatum dexter, especially for stenosis post-balloon dilation.

CRISP: Catheterization RISk score for Pediatrics: A Report from the Congenital Cardiac Interventional Study Consortium (CCISC).

OBJECTIVES: We sought to develop a scoring system that predicts the risk of serious adverse events (SAE's) for individual pediatric patients undergoing cardiac catheterization procedures. BACKGROUND: Systematic assessment of risk of SAE in pediatric catheterization can be challenging in view of a wide variation in procedure and patient complexity as well as rapidly evolving technology. METHODS: A 10 component scoring system was originally developed based on expert consensus and review of the existing literature. Data from an international multi-institutional catheterization registry (CCISC) between 2008 and 2013 were used to validate this scoring system. In addition we used multivariate methods to further refine the original risk score to improve its predictive power of SAE's. RESULTS: Univariate analysis confirmed the strong correlation of each of the 10 components of the original risk score with SAE attributed to a pediatric cardiac catheterization (P < 0.001 for all variables). Multivariate analysis resulted in a modified risk score (CRISP) that corresponds to an increase in value of area under a receiver operating characteristic curve (AUC) from 0.715 to 0.741. CONCLUSION: The CRISP score predicts risk of occurrence of an SAE for individual patients undergoing pediatric cardiac catheterization procedures.

Standardizing radiation dose reporting in the pediatric cardiac catheterization laboratory-a multicenter study by the CCISC (Congenital Cardiovascular Interventional Study Consortium).

OBJECTIVES: We examine normalized air Kerma area product (PKA ) by body weight (PKA /BW) as a reference value of radiation dose and benchmark PKA /BW in pediatric laboratories using a multicenter registry database. BACKGROUND: Reduction of radiation dose is an important quality improvement task in pediatric cardiac catheterization laboratories. Physicians need to agree on a standard method of reporting radiation dose that would allow comparisons to be made between operators and institutions. METHODS: This was a multicenter observational study of radiation dose in pediatric laboratories. Patient demographic, procedural and radiation data including fluoroscopic time and PKA (µGy m(2) ) were analyzed. PKA /BW was obtained by indexing PKA to body weight. RESULTS: A total of 8,267 pediatric catheterization procedures (age <18 years) were included from 16 institutions. The procedures consisted of diagnostic (n = 2,827), transplant right ventricular (RV) biopsy (n = 1,172), and interventional catheterizations (n = 4268). PKA correlated with body weight better than with age and best correlated with weight-fluoroscopic time product. PKA /BW showed consistent values across pediatric ages. Interventional catheterizations had the highest PKA /BW (50th, 75th, and 90th percentiles: 72, 151, and 281 µGy m(2) /kg), followed by diagnostic (59, 105, and 175 µGy m(2) /kg) and transplant RV biopsy (27, 79, and 114 µGy m(2) /kg). CONCLUSION: PKA /BW appeared to be the most reliable standard to report radiation dose across all procedure types and patient age. We recommend PKA /BW to be used as the standard unit in documenting radiation usage in pediatric laboratories and can be used to evaluate strategies to lower radiation dosage in pediatric patients undergoing cardiac catheterizations. © 2014 Wiley Periodicals, Inc.

Frequency of superior vena cava obstruction in pediatric heart transplant recipients and its relation to previous superior cavopulmonary anastomosis.

The risk factors for superior vena cava (SVC) obstruction after pediatric orthotopic heart transplantation (OHT) have not been identified. This study tested the hypothesis that pretransplant superior cavopulmonary anastomosis (CPA) predisposes patients to SVC obstruction. A retrospective review of the Pediatric Cardiac Care Consortium registry from 1982 through 2007 was performed. Previous CPA, other cardiac surgeries, gender, age at transplantation, and weight at transplantation were assessed for the risk of developing SVC obstruction. Death, subsequent OHT, or reoperation involving the SVC were treated as competing risks. Of the 894 pediatric OHT patients identified, 3.1% (n = 28) developed SVC obstruction during median follow-up of 1.0 year (range: 0 to 19.5 years). Among patients who developed SVC obstruction, 32% (n = 9) had pretransplant CPA. SVC surgery before OHT was associated with posttransplant development of SVC obstruction (p <0.001) after adjustment for gender, age, and weight at OHT and year of OHT. Patients with previous CPA had increased risk for SVC obstruction compared with patients with no history of previous cardiac surgery (hazard ratio 10.6, 95% confidence interval: 3.5 to 31.7) and to patients with history of non-CPA cardiac surgery (hazard ratio 4.7, 95% confidence interval: 1.8 to 12.5). In conclusion, previous CPA is a significant risk factor for the development of post-heart transplant SVC obstruction.

Pericardial effusion after pediatric hematopoietic cell transplant.

PE can occur following HCT. However, the incidence, etiology, risk factors, and treatment remain unclear. We performed a retrospective study evaluating 355 pediatric recipients of HCT treated at a single institution between January 2005 and August 2010. No cases of PE were identified in the autologous HCT (auto-HCT) recipients (0/43), while 19% (57/296) of allogeneic HCT (allo-HCT) developed PE. Among the 57 PE patients, 40 (70%) were males; the median age at transplantation was 6.6 yr (0.1-17.3 yr). Thirty-six patients (63%) had significant PE with 23 patients (40%) treated by pericardiocentesis, and 19 (33%) experiencing recurrent PE. OS rates for patients who developed PE were 84% at 100 days and 65% at three yr after HCT. Risk factors associated with PE on multivariate analysis included myeloablative conditioning (p = 0.01), delayed neutrophil engraftment (p < 0.01), and CMV + serostatus of the recipient (p = 0.03). Recipients with non-malignant diseases were significantly less likely to die after development of PE (p = 0.02 and 0.004 when comparing with standard and high-risk diseases, respectively). In summary, PE is a common and significant complication of pediatric allo-HCT. Prospective studies are needed to better determine the etiology and optimal method of PE treatment after HCT.

Experimental evaluation of a new articulated Amplatzer ductal occluder device without fabric.

OBJECTIVES: To describe a new percutaneous PDA device. BACKGROUND: The ADO II was developed by AGA Medical for closure of small-moderate sized PDAs via a small delivery catheter from an antegrade or retrograde catheter approach. The objective of this study was to evaluate the technical feasibility, safety, and efficacy of the ADO II in a canine PDA model. METHODS: The ADO-II consists of multi-layer nitinol wire braid with symmetric retention disks and an articulating connecting center waist, without sewn-in polyester, that can be delivered though a 4-5F catheter. A PDA was surgically created in nine dogs. Transcatheter occlusion of the PDA was performed using the ADO II. Angiographic and hemodynamic data were obtained at 7, 30, 60, and 90 days post-procedure. The devices were then harvested for pathology. RESULTS: Devices were placed transarterially (n = 8) and transvenously (n = 1). All PDAs were occluded and there were no significant pressure gradients (P > 0.05) at the immediate and 90 post-implant evaluations. Pathology found endothelial coverage on all aortic and pulmonary disks, except at the tip of the microscrew. There were no procedural complications. One canine was euthanized 4 hr after device implant because of a clinical deterioration. The staff veterinarian and pathologist concluded that the animal's illness was not device related. CONCLUSIONS: The Amplatzer ADO II devices can be safely deployed in animal models of PDAs, with complete resolution of the PDA shunt. The lower profile and symmetry of the ADO II allows for venous or arterial approach and smaller delivery catheter size. The ADO-II is expected to be a preferred alternative for closure of small-moderate PDAs.

Ductal stent and cavo-atrial sac occlusion in an adult with profound cyanosis after palliated cyanotic congenital heart disease.

We report a unique combination of PDA stent placement and occlusion of a persistent cavo-atrial connection in an adult with complex cyanotic congenital heart disease. The unusual anatomy and physiology with prior palliative surgery were amenable to catheterization intervention and have resulted in marked clinical improvement.

Pulmonary venous wedge pressure provides an accurate assessment of pulmonary artery pressure in children with a bidirectional Glenn shunt.

PURPOSE: In circulations with pulsatile pulmonary artery flow the pulmonary venous wedge pressure (PVWp) has been validated as a good estimate of pulmonary artery pressure (PAp), when PAp is low. The purpose of this study was to validate PVWp estimates of PAp in the less-pulsatile pulmonary circulation of children after bidirectional Glenn shunts. METHODS: A retrospective study was performed of 22 simultaneous measurements of PVWp and PAp made during 20 catheterizations in 19 children who had undergone bidirectional Glenn procedures. The PAp was measured directly from the branch PA ipsilateral to the side of the PVWp, or in the SVC. Pulmonary resistance (Rp) was calculated with both PAp and PVWp, to assess the impact of PAp estimates on Rp determinations. RESULTS: Patients ranged in age from 5 months to 10.7 years. There were a variety of univentricular cardiac malformations in the study group. Two children had antegrade pulmonary blood flow in addition to a bidirectional Glenn shunt. The mean PAp ranged from 4 to 14 mmHg, while mean PVWp ranged from 3 to 15 mmHg. Mean PVWp never differed from mean PAp by more than 3 mmHg. There was a significant linear relation between mean PAp and PVWp: PAp = 0.86 (PVWp) + 2.0 (R2 = 0.89; P < 0.0001). PVWp provided a good approximation of PAp regardless of the presence (n = 2) or absence (n = 19) of antegrade pulmonary flow. There was a good linear correlation between the Rp calculated by both methods (RpPAp = 0.9 (RpVWp) + 0.5; R2 = 0.74; P < 0.0001). CONCLUSION: The mean PVWp provides a close approximation of mean PAp in children with a bidirectional Glenn shunt and provides valuable hemodynamic information in cases where direct PAp measurements are unavailable.