Finite element modeling with patient-specific geometry to assess clinical risks of percutaneous pulmonary valve implantation.

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.

Enhancing Congenital Cardiac Postprocedural Care: A QR Code-Enabled Medical Bracelet Pilot Study.

The study aimed to evaluate the feasibility of using QR code-enabled medical bracelets for congenital heart disease (CHD) patients after hospital discharge to ensure quick communication of vital information to other medical personnel in emergency situations. A prospective study was conducted where QR code-enabled medical bracelets were given to families of postoperative pediatric cardiac patients. The QR code linked to a secure medical information sheet detailing the patient's cardiac history. Post-study surveys were completed by providers and families to assess their experiences with the bracelet. Of the 20 participants enrolled, 65% used the QR bracelet when seeking medical care. 55% found the bracelet useful, and 70% rated their experience as either "positive" or "very positive". Additionally, 80% recommended the bracelet for other patients undergoing cardiac procedures. The use of QR code bracelets for postoperative CHD patients has shown high levels of satisfaction from families and providers, potentially reducing medical errors and treatment delays.

Assessing the State of Training in Congenital Interventional Cardiology: A Global Survey of Program Directors.

This study aimed to evaluate the current state of congenital interventional cardiology training worldwide, with a focus on case volumes, competency assessment, and the need for ongoing mentorship during early career stages. A survey was conducted among program directors (PDs) of congenital interventional training programs across the globe. The survey gathered data on training pathways, case volumes, types of procedures performed, trainee competency assessment, and the role of ongoing mentorship. Of the 79 PDs who completed the survey, it was observed that training pathways and case volumes varied significantly, particularly between the United States and other countries. Most PDs reported an annual laboratory case volume of >500 congenital cardiac cases, with most cases being interventional. While trainees demonstrated competency in simple procedures (diagnostic cases, simple ASD closure), complex interventions (such as patent ductus arteriosus closure in premature infants) require ongoing mentorship for graduates. PDs recommended a minimum case volume of 400 total cases for trainees, including 250 interventional cases. In addition to case volumes, assessing trainee competency was deemed important, with clinical reasoning, judgment, skillset, teamwork, and complication management being key areas of evaluation. The study highlights the variability in congenital interventional cardiology training and the need for ongoing mentorship during the early career years. External mentorship programs, facilitated by national and international societies, are proposed to provide critical support for early career interventionalists thus enhancing patient care for congenital heart disease. Ultimately, the findings of this survey may serve as a framework for future training standards and guidelines in this specialized field.

Invasive haemodynamics predict outcomes in paediatric pulmonary artery hypertension.

BACKGROUND: Invasive haemodynamics are often performed for initiating and guiding pulmonary artery hypertension therapy. Little is known about the predictive value of invasive haemodynamic indices for long-term outcomes in children with pulmonary artery hypertension. We aimed to evaluate invasive haemodynamic data to help predict outcomes in paediatric pulmonary artery hypertension. METHODS: Patients with pulmonary artery hypertension who underwent cardiac catheterisation (2006-2019) at a single centre were included. Invasive haemodynamic data from the first cardiac catheterisation and clinical outcomes were reviewed. The combined adverse outcome was defined as pericardial effusion (due to right ventricle failure), creation of a shunt for pulmonary artery hypertension (atrial septal defect or reverse Pott's shunt), lung transplant, or death. RESULTS: Among 46 patients with a median [interquartile range (IQR)] age of 13.2 [4.1-44.7] months, 76% had CHD. Median mean pulmonary artery pressure was 37 [28-52] mmHg and indexed pulmonary vascular resistance was 6.2 [3.6-10] Woods units × m2. Median pulmonary artery pulsatility index was 4.0 [3.0-4.7] and right ventricular stroke work index was 915 [715-1734] mmHg mL/m2. After a median follow-up of 2.4 years, nine patients had a combined adverse outcome (two had a pericardial effusion, one underwent atrial level shunt, one underwent reverse Pott's shunt, and six died). Patients with an adverse outcome had higher systolic and mean pulmonary artery pressures, higher diastolic and transpulmonary pressure gradients, higher indexed pulmonary vascular resistance, higher pulmonary artery elastance, and higher right ventricular stroke work index (p < 0.05 each). CONCLUSION: Invasive haemodynamics (especially mean pulmonary artery pressure and diastolic pressure gradient) obtained at first cardiac catheterisation in children with pulmonary artery hypertension predicts outcomes.

Qualifying a novel clinical trial endpoint (iBOX) predictive of long-term kidney transplant outcomes.

New immunosuppressive therapies that improve long-term graft survival are needed in kidney transplant. Critical Path Institute's Transplant Therapeutics Consortium received a qualification opinion for the iBOX Scoring System as a novel secondary efficacy endpoint for kidney transplant clinical trials through European Medicines Agency's qualification of novel methodologies for drug development. This is the first qualified endpoint for any transplant indication and is now available for use in kidney transplant clinical trials. Although the current efficacy failure endpoint has typically shown the noninferiority of therapeutic regimens, the iBOX Scoring System can be used to demonstrate the superiority of a new immunosuppressive therapy compared to the standard of care from 6 months to 24 months posttransplant in pivotal or exploratory drug therapeutic studies.

Qualifying a Novel Clinical Trial Endpoint (iBOX) Predictive of Long-Term Kidney Transplant Outcomes.

New immunosuppressive therapies that improve long-term graft survival are needed in kidney transplant. Critical Path Institute's Transplant Therapeutics Consortium received a qualification opinion for the iBOX Scoring System as a novel secondary efficacy endpoint for kidney transplant clinical trials through European Medicines Agency's qualification of novel methodologies for drug development. This is the first qualified endpoint for any transplant indication and is now available for use in kidney transplant clinical trials. Although the current efficacy failure endpoint has typically shown the noninferiority of therapeutic regimens, the iBOX Scoring System can be used to demonstrate the superiority of a new immunosuppressive therapy compared to the standard of care from 6 months to 24 months posttransplant in pivotal or exploratory drug therapeutic studies.

Catheter ablation of atrioventricular nodal reentrant tachycardia, when AVNRT presented as a fetus or infant.

BACKGROUND: Atrioventricular nodal reentrant tachycardia (AVNRT) does not commonly present during infancy. Although relative safety of catheter ablation of AVNRT has been demonstrated in pediatrics, this procedure is rarely indicated in children <15 kg. METHODS: Retrospective review of seven cases of AVNRT that presented in children younger than 1 year of age and required catheter ablation for definitive management. Electrophysiology (EP) study was planned with two or three catheters. Area of ablation determined by voltage mapping, propagation sinus wave collision and slow pathway potential location. Ablation performed with cryothermal energy. No fluoroscopy was used. RESULTS: Presentation ranged from 36 weeks of gestation to 11 months of age. Two presented in fetal life and two in the neonatal period. The median age of ablation was 20 months (range 17-31 months). The median weight at ablation was 11.4 kg (range 8.9-14.9 kg). Median follow-up time was 16 months. All had typical AVNRT. The median tachycardia cycle length was 216 ms. 100% successful rate using cryoablation. No complications. No recurrence of tachycardia during the follow-up period. CONCLUSION: Slow AV nodal pathway cryoablation may be safely performed, with good short and medium-term outcomes in patients under 15 kg.

Bilateral sixth nerve palsy with subdural hematoma: a unique presentation of B12 deficiency.

Vitamin B12 is inextricably associated with the development and maintenance of neuronal functions. It is classically associated with subacute combined degeneration and peripheral neuropathy; however, cranial neuropathy is uncommon. We observed the rarest neurological manifestation of B12 deficiency. A 12 months infant had history of lethargy, irritability, anorexia, paleness, vomiting, and neurodevelopmental delay for 2 months. He also developed inattention and altered sleep pattern. His mother noticed bilateral inward rotation of both eyes. On examination, the infant had bilateral lateral rectus palsy. The infant was found to have anemia (7.7g/dL) and severe B12 deficiency (74pg/mL). On MRI, there was cerebral atrophy, subdural hematoma (SDH) and wide cisternal spaces and sulci. On supplementation with cobalamin, he improved clinically though mild restriction of lateral gaze on the left side persists. Follow up MRI showed significant improvement in cerebral atrophy with resolution of SDH. To date, such clinical presentation of B12 deficiency has never been reported. The authors suggest B12 supplementation for at risk population esp at antenatal stage and lactating mothers in national programs. The treatment of this condition should be initiated early to prevent long term sequelae.

Transcatheter Closure of a Coronary Artery Fistula in a Neonate with Tetralogy of Fallot.

Coronary artery-to-pulmonary artery fistulae are a not uncommon finding in patients with Tetralogy of Fallot (TOF) and collateral-dependent pulmonary blood flow. Management for these fistulae is often primary surgical ligation or unifocalization at the time of complete repair, dependent on the presence of dual blood flow to the involved areas. We present the case of a 32-week premature boy weighing 1.79 kg with TOF, confluent branch pulmonary arteries, major aortopulmonary collaterals, and right coronary artery to main pulmonary artery fistula. The patient demonstrated evidence of coronary steal into the pulmonary vasculature with an elevation in the troponin level without hemodynamic instability, and subsequently underwent successful transcatheter occlusion of the fistula via right common carotid access using a Medtronic 3Q microvascular plug. This case demonstrates the realistic potential for early coronary steal in this physiology and possibility of transcatheter therapy even in a small neonate.

Over-expansion of right ventricle to pulmonary artery conduits during transcatheter pulmonary valve placement.

OBJECTIVES: To determine the safety and feasibility of over-expansion of right ventricle to pulmonary artery conduits during transcatheter pulmonary valve placement. BACKGROUND: Transcatheter pulmonary valve placement is an alternative to surgical pulmonary valve replacement. Traditionally, it was thought to be unsafe to expand a conduit to >110% of its original size. METHODS: This retrospective cohort study from two centers includes patients with right ventricle to pulmonary artery conduits with attempted transcatheter pulmonary valve placement from 2010 to 2017. Demographic, procedural, echocardiographic and follow-up data, and complications were evaluated in control and overdilation (to >110% original conduit size) groups. RESULTS: One hundred and seventy-two patients (51 overdilation and 121 control) had attempted transcatheter pulmonary valve placement (98% successful). The overdilation group was younger (11.2 versus 16.7 years, p < 0.001) with smaller conduits (15 versus 22 mm, p < 0.001); however, the final valve size was not significantly different (19.7 versus 20.2 mm, p = 0.2). Baseline peak echocardiographic gradient was no different (51.8 versus 55.6 mmHg, p = 0.3). Procedural complications were more frequent in overdilation (18%) than control (7%) groups (most successfully addressed during the procedure). One patient from each group required urgent surgical intervention, with no procedural mortality. Follow-up echocardiographic peak gradients were similar (24.1 versus 26 mmHg, p = 0.5). CONCLUSIONS: Over-expansion of right ventricle to pulmonary artery conduits during transcatheter pulmonary valve placement can be performed successfully. Procedural complications are more frequent with conduit overdilation, but there was no difference in the rate of life-threatening complications. There was no difference in valve function at most recent follow-up, and no difference in rate of reintervention. The long-term outcomes of transcatheter pulmonary valve placement with conduit over-expansion requires further study.

Stenting of ductus venosus as a palliation for portal hypertension because of neonatal cirrhosis.

Portal hypertension because of liver cirrhosis is a significant cause of morbidity and mortality. Treatment options in these patients include liver transplant, symptomatic treatment of oesophageal varices via endoscopic treatment and symptomatic management of ascites. Portosystemic shunt creation can be challenging in newborns and infants. We present a newborn with Trisomy 21, severe portal hypertension secondary to neonatal cirrhosis, oesophageal varices and upper GI bleeding, severe ascites refractory to medical management who underwent ductus venosus stenting as a palliative procedure. He demonstrated remarkable clinical improvement with no subsequent upper GI bleed and resolution of ascites till his last follow-up at 12 months of age. To the best of our knowledge, stenting of the patent ductus venosus to create a portosystemic shunt to relieve portal hypertension has not been reported in English literature.

Comparison of Patent Ductus Arteriosus Stent and Blalock-Taussig Shunt as Palliation for Neonates with Sole Source Ductal-Dependent Pulmonary Blood Flow: Results from the Congenital Catheterization Research Collaborative.

Patent ductus arteriosus (PDA) stenting is an accepted method for securing pulmonary blood flow in cyanotic neonates. In neonates with pulmonary atresia and single source ductal-dependent pulmonary blood flow (SSPBF), PDA stenting remains controversial. We sought to evaluate outcomes in neonates with SSPBF, comparing PDA stenting and surgical Blalock-Taussig shunt (BTS). Neonates with SSPBF who underwent PDA stenting or BTS at the four centers of the Congenital Catheterization Research Collaborative from January 2008 to December 2015 were retrospectively reviewed. Reintervention on the BTS or PDA stent prior to planned surgical repair served as the primary endpoint. Additional analyses of peri-procedural complications, interventions, and pulmonary artery growth were performed. A propensity score was utilized to adjust for differences in factors. Thirty-five patients with PDA stents and 156 patients with BTS were included. The cohorts had similar baseline characteristics, procedural complications, and mortality. Interstage reintervention rates were higher in the PDA stent cohort (48.6% vs. 15.4%, p < 0.001).

Long-term outcomes after repair for anomalous right coronary artery from the pulmonary artery.

Anomalous right coronary artery from pulmonary artery (ARCAPA) is a rare congenital heart disease that can lead to abnormal coronary perfusion and a need for surgical repair. Here, we report the outcomes of patients who underwent ARCAPA surgery within the Pediatric Cardiac Care Consortium (PCCC), a North American registry of interventions for paediatric heart diseases. We queried the PCCC for patients undergoing surgical repair for ARCAPA at <18 years of age between 1982 and 2003. Outcomes were obtained from the PCCC and after linkage with the National Death Index (NDI) and the Organ Procurement and Transplantation Network (OPTN) through 2019. Twenty-four patients (males: 15) were identified having surgery for ARCAPA at a median age of 5.8 (IQR 2.7-10.3) years. Of them, 23 cases were considered "simple" (without major intracardiac disease) and one "complex" (co-existing with tetralogy of Fallot). Five patients presented with symptoms [chest pain (1), dyspnoea on exertion (2) or history of syncope (2)]; while the remaining 19 patients were referred for evaluation of either murmur or co-existing CHD. There was no in-hospital mortality after the surgical repair. Fourteen patients had sufficient identifiers for NDI/OPTN linkage; among them, only one death occurred from unrelated non-cardiac causes within a median period of 19.4 years of follow-up (IQR: 18-24.6). Outcomes were excellent after reimplantation up to 25 years later and further longitudinal monitoring is important to understand the interaction of pre-existing coronary pathology with the effects of ageing.

Racial and ethnic disparities in coronary, vascular, structural, and congenital heart disease.

Cardiovascular disease (CVD) remains the leading cause of death in the United States. However, percutaneous interventional cardiovascular therapies are often underutilized in Blacks, Hispanics, and women and may contribute to excess morbidity and mortality in these vulnerable populations. The Society for Cardiovascular Angiography and Interventions (SCAI) is committed to reducing racial, ethnic, and sex-based treatment disparities in interventional cardiology patients. Accordingly, each of the SCAI Clinical Interest Councils (coronary, peripheral, structural, and congenital heart disease [CHD]) participated in the development of this whitepaper addressing disparities in diagnosis, treatment, and outcomes in underserved populations. The councils were charged with summarizing the available data on prevalence, treatment, and outcomes and elucidating potential reasons for any disparities. Given the huge changes in racial and ethnic composition by age in the United States (Figure 1), it was difficult to determine disparities in rates of diagnosis and we expected to find some racial differences in prevalence of disease. For example, since the average age of patients undergoing transcatheter aortic valve replacement (TAVR) is 80 years, one may expect 80% of TAVR patients to be non-Hispanic White. Conversely, only 50% of congenital heart interventions would be expected to be performed in non-Hispanic Whites. Finally, we identified opportunities for SCAI to advance clinical care and equity for our patients, regardless of sex, ethnicity, or race.

Pulmonary valve replacement via left anterior minithoracotomy: Lessons learned and early experience.

OBJECTIVE: Median sternotomy has been the standard for pulmonary valve replacement (PVR) in patients with free pulmonary regurgitation (PR) and right ventricular enlargement. With the introduction of transcatheter therapy, the search for an alternate to sternotomy is mandated. We present our early experience with a limited anterior left thoracotomy approach. METHODS: We used a left anterior mini-thoracotomy in six male patients (15 ± 1.94 years of age) who developed progressive right ventricular enlargement due to chronic PR. RESULTS: Primary diagnoses were tetralogy of Fallot in five patients and pulmonary atresia with an intact septum in another. Four patients had previous median sternotomy with transannular patch repair. The mean right ventricular end-diastolic volume index was 189 ± 27.13 ml/m2 . The procedure was feasible in all patients. All patients had satisfactory adult size pulmonary bioprosthesis (25 or 27 mm valve), with a mean peak gradient of 18 ± 2.40 mmHg across the prosthesis at discharge. All patients were extubated intraoperatively at the end of the procedure and required no intraoperative transfusions. There were no early or late mortalities. Early morbidities included left hemidiaphragm paralysis in one patient, and re-sternotomy for prosthetic valve endocarditis in one. One patient required late reoperation for a common femoral artery pseudoaneurysm. CONCLUSIONS: Minimally invasive access for PVR is feasible in both primary and repeat settings, through a limited anterior left minithoracotomy in the absence of intracardiac shunts and the need for other concomitant cardiac procedures. Longer-term studies with a larger number of patients are needed to compare the efficacy of this approach to standard sternotomy.

Anatomic Approach and Outcomes in Children Undergoing Percutaneous Pericardiocentesis.

Pericardiocentesis is traditionally performed using a subxiphoid approach. Hepatomegaly or loculated and noncircumferential effusions warrant nonstandard approaches to drain effusions; echocardiographic guidance has made these less traditional, non-subxiphoid approaches feasible. The study is aimed at comparing clinical outcomes of the subxiphoid and non-subxiphoid approaches to percutaneous pericardiocentesis in a pediatric population. This is a retrospective chart review of all children undergoing percutaneous pericardiocentesis from August 2008 to December 2019 at a single-center. A total of 104 patients underwent echocardiography-guided pericardiocentesis during the timeframe. Additionally, fluoroscopy was also used in 80 patients. Hematopoietic stem cell transplantation was the most common underlying diagnosis (n = 53, 50.9%). A non-subxiphoid approach was used in 58.6% (n = 61) of patients. The fifth and sixth intercostal spaces were the most commonly used (n = 17 each). The non-subxiphoid group tended to be older (95.9 vs. 21.7 months, p = 0.006) and weighed more (23.6 vs. 11.2 kgs, p = 0.013) as compared to the subxiphoid group. Non-subxiphoid approach was associated with shorter procedure times (21 vs. 37 min, p = 0.005). No major complications were seen. Five minor complications occurred and were equally distributed in the two groups. Complications were more likely in younger patients (p = 0.047). The technique and anatomic approach to pericardiocentesis, and the location or size of effusion did not influence the risk of complications. Echocardiography-guided percutaneous pericardiocentesis in children was associated with low complication rates in this single-center pediatric experience. The use of a non-traditional, non-subxiphoid approach was associated with shorter procedure times and did not significantly affect complication rates.

Impact of Treatment Strategy on Outcomes in Isolated Pulmonary Artery of Ductal Origin.

Isolated pulmonary artery (PA) of ductal origin (IPADO) is a rare cardiac defect which requires surgical repair, with or without preceding palliation. We sought to determine the impact of treatment strategy on outcomes. Retrospective study of consecutive patients with IPADO that underwent staged or primary repair from 1/05 to 9/16 at 6 Congenital Cardiac Research Collaborative centers. Patients with single ventricle physiology, major aortopulmonary collaterals, or bilateral IPADO were excluded. Primary outcome was isolated PA z-score at late follow-up. Secondary outcomes included PA symmetry index (isolated:confluent PA diameter) and reintervention burden. Propensity score adjustment was used to account for baseline differences. Of 60 patients in the study cohort, 26 (43%) underwent staged and 34 (57%) primary repair. The staged and primary repair groups differed in weight at diagnosis and presence of other heart disease but not in baseline PA dimensions. Staged patients underwent ductal stent (n = 16) or surgical shunt (n = 10) placement followed by repair at 210 vs. 21 days in the primary repair group (p < 0.001). At median follow-up of 4.5 years post-repair, after adjustment, isolated PA z-score (- 0.74 [- 1.75, - 0.26] vs. - 1.95 [- 2.91, - 1.59], p = 0.012) and PA symmetry index (0.81 [0.49, 1.0] vs. 0.55 [0.48, 0.69], p = 0.042) significantly favored the staged repair group. Freedom from PA reintervention was not different between groups (adjusted HR 0.78 [0.41, 1.48]; p = 0.445). A staged approach to repair of IPADO is associated with superior isolated PA size and symmetry at late follow-up. Consideration should be given to initial palliation in IPADO patients, when feasible.

Angiographic evidence of backward compression wave: systolic compression of septal perforators in a child with hypertrophic cardiomyopathy.

Intracoronary wave intensity analysis in hypertrophic cardiomyopathy has shown a large backward compression wave due to compressive deformation of the intramyocardial coronary arteries in systole. The authors describe the angiographic evidence of this backward compression wave, which has not been described in this physiological context and can be a marker of poor prognosis.

Gore Cardioform atrial septal occluder: deployment procedure and techniques for closing challenging secundum atrial septal defects.

Ostium secundum atrial septal defects are mostly closed in the cardiac catheterisation laboratories using either Amplatzer® (Abbott Laboratories, IL) atrial septal occluder, Gore® Cardioform septal occluder and more recently using the recently approved (US FDA approval June 2019) Gore® Cardioform atrial septal defect occluder (W. L. Gore & Associates, AZ). Similar to any new device in the market, there is a learning curve to the deployment of this device. We therefore aim to report the key features about this new Gore Cardioform atrial septal defect occluder device with special emphasis on technical aspects that can be employed during transcatheter closure of challenging ostium secundum atrial septal defects using this device.

Use of carotid and axillary artery approach for stenting the patent ductus arteriosus in infants with ductal-dependent pulmonary blood flow: A multicenter study from the congenital catheterization research collaborative.

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.