Accessory pathway localization with probabilistic density maps generated by a mobile application: Assessment of a full pre-excitation net-vector method.

INTRODUCTION: Precise electrocardiographic localization of accessory pathways (AP) can be challenging. Seminal AP localization studies were limited by complexity of algorithms and sample size. We aimed to create a nonalgorithmic method for AP localization based on color-coded maps of AP distribution generated by a web-based application. METHODS: APs were categorized into 19 regions/types based on invasive electrophysiologic mapping. Preexcited QRS complexes were categorized into 6 types based on polarity and notch/slur. For each QRS type in each lead the distribution of APs was visualized on a gradient map. The principle of common set was used to combine the single lead maps to create the distribution map for AP with any combination of QRS types in several leads. For the validation phase, a separate cohort of APs was obtained. RESULTS: A total of 800 patients with overt APs were studied. The application used the exploratory data set of 553 consecutive APs and the corresponding QRS complexes to generate AP localization maps for any possible combination of QRS types in 12 leads. Optimized approach (on average 3 steps) for evaluation of preexcited electrcardiogram was developed. The area of maximum probability of AP localization was pinpointed by providing the QRS type for the subsequent leads. The exploratory data set was validated with the separate cohort of APs (n = 256); p = .23 for difference in AP distribution. CONCLUSIONS: In the largest data set of APs to-date, a novel probabilistic and semi-automatic approach to electrocardiographic localization of APs was highly predictive for anatomic localization.

Percutaneous pulmonary valve implantation in a patient with a single pulmonary artery and distal narrowing.

Percutaneous pulmonary valve implantation is established as a safe and effective method of treating patients with disfunction of right ventricular outflow tract. Modifications of this method allow for an increasingly wider use of this less invasive treatment. We present a staged percutaneous pulmonary valve implantation into a single-branch pulmonary artery in a paediatric patient with tetralogy of Fallot after patch repair.

Virtual reality modelling for planning of percutaneous first step palliation in a newborn with heterotaxy syndrome.

We report the first-stage percutaneous palliation in a newborn with a rare heterotaxy syndrome variant including interrupted inferior vena cava, partial anomalous pulmonary venous drainage, and restrictive interatrial communication. Virtual reality imaging aided visualisation, decision-making, and planning. Successful atrial septoplasty performed via the internal jugular vein and anomalous pulmonary vein was followed by stenting of ductus arteriosus.

Virtual reality modelling in a child after multiple interventions for hypoplastic aortic arch and coarctation.

We present the benefits of advanced multimodality imaging and virtual reality modelling in the diagnosis and treatment planning of a child with aneurysms after numerous interventions for treatment of a hypoplastic aortic arch and coarctation.

Predictors of Left Ventricular Outflow Tract Obstruction After Conventional Repair for Patients with Interrupted Aortic Arch or Coarctation of the Aorta, Combined with Ventricular Septal Defect: A Single-Center Experience.

Left ventricular outflow tract obstruction (LVOTO) affects survival and reoperation rates after surgical treatment of patients with interruption of the aortic arch (IAA) or coarctation of the aorta (CoA) with ventricular septal defect (VSD). The aim of the study was to determine predictors of LVOTO and to evaluate the relationship between aortic valve (AoV) morphology and the re-intervention rate. Retrospective review of patients, who underwent a conventional repair for IAA/CoA with VSD at a tertiary referral center between 1996 and 2017. The preoperative demographic data as well as pre- and post-operative echocardiographic parameters and re-interventions were reviewed. In the median follow-up of 8.3 years (range of 6.15-10.27) 5 patients (11.9%) from a total of 47 patients included in the study presented with a significant LVOTO. Four of them required reoperation after median period of 2.3 years (range of 0.3-7.9) after the initial surgery. Multivariable logistic regression identified AoV z-score (OR 0.44, p = 0.017) as predictor of LVOTO. The mean AoV z-score before the primary repair was significantly smaller in those with LVOTO as compared to those with unobstructed flow from the LV (- 3.58 ± 1.96 vs. - 1.44 ± 1.55; p = 0.0016). At 1-year follow-up, both groups showed an increase in the AoV z-score (p = 0.98). The re-intervention rate after primary repair (both surgical procedures and percutaneous interventions), either for LVOTO or reCoA, was higher in patients with AoV z-score ≤ - 3 (p = 0.007 vs. p = 0.46) and those, whose aortic annulus was less or equal than patient's weight (kg) + 1.5 mm as compared to those with larger aortic annulus (p = 0.03 vs. p = 0.16). In patients after surgical treatment of IAA/CoA with VSD, the AoV z-score at diagnosis is a significant risk factor for reoperation for LVOTO. With age, AoV growth and z-score improvement is expected. Small AoV at diagnosis is correlated with increased rate of re-intervention for LVOTO and reCoA.

Early clinical experience with the straight design of Venus P-valve™ in dysfunctional right ventricular outflow tracts.

OBJECTIVES: To assess the initial procedural and short to medium-term experience with the straight design of the Venus P-valve™ (Venus MedTech, Hangzhou, China) in dysfunctional right ventricular outflow tracts (RVOT). BACKGROUND: The Melody™ valve (Medtronic, Minneapolis, Minnesota) has been the only percutaneous valve option for smaller RVOT conduits. The straight Venus P-valve™ may provide an alternative to the Melody™ valve. METHODS: Retrospective data collection of patient characteristics, procedural data, clinical and imaging follow-up of the straight Venus P-valve™. RESULTS: Nine patients (four female) with a mean age of 23.1 ± 7.5 years and a mean weight of 72.7 ± 29.4 kg underwent straight Venus P-valve™ implantation between 03/2014 and 06/2016. All patients had right ventricle-to-pulmonary artery conduits which were pre-stented before the valve implantation. All valves were deployed successfully without any significant procedural complications. During the mean follow-up of 24 ± 9.1 months, there were no valve related re-interventions or deterioration in valve performance. There was one case of insignificant, single wire frame fracture and no cases of endocarditis. The cohort demonstrated a reduction in pulmonary regurgitation and tricuspid regurgitation, which was sustained throughout the follow-up. Similarly the gradient across the RVOT tract did not significantly increase. CONCLUSIONS: Implantation of the straight Venus P-valve™ has provided satisfactory short to mid-term results with high success rates and no complications and may be considered as an alternative option in patients with RVOT dysfunction.

"Apple does not fall far from the tree" - subclinical atherosclerosis in children with familial hypercholesterolemia.

BACKGROUND: Familial hypercholesterolemia (FH) increases the risk of atherosclerosis in children and adults. Atherosclerotic cardiovascular disease in young patients FH is usually subclinical but recognition of children with more pronounced changes is crucial for adjusting effective management. Aim of this research was to use ultrasonography with two-dimensional speckle tracking (2DST) and tonometry to evaluate atherosclerotic changes in patients with FH (parents and their offspring). METHODS: Applanation tonometry and carotid arteries sonography with evaluation of the intima-media complex thickness (IMCT) and application of the 2DST were performed in 20 families with FH (20 parents and 29 children). The same size control group (age and sex matched) was included. Results were compared between peers and between generations together with the correlation analysis. RESULTS: Adults with FH, in comparison with healthy peers, presented significantly more atherosclerotic plaques (9 vs. 2, p = 0.0230), had significantly thicker IMC (0.84 ± 0.19 vs. 0.56 ± 0.06 mm, p < 0.0001) and had stiffer arterial wall (for stain: 6.25 ± 2.3 vs. 8.15 ± 2.46, p = 0.0103). In children from both groups there were no atherosclerotic plaques and IMCT did not differ significantly (0.42 ± 0.07 vs. 0.39 ± 0.04, p = 0.1722). However, children with FH had significantly stiffer arterial wall according to 2DST (for strain: 9.22 ± 3.4 vs. 11.93 ± 3.11, p = 0.0057) and tonometry (for the pulse wave velocity: 4.5 ± 0.64 vs.3.96 ± 0.62, p = 0.0047). These parameters correlated with atherosclerosis surrogates in their parents (p < 0.001) but were not significantly affected by presence of presumed pathogenic gene variant. CONCLUSIONS: Children with FH presented subclinical atherosclerosis manifested as decreased arterial wall elasticity. Degree of stiffening was associated with advancement of atherosclerosis in their parents but did not present significant association with gene variants. Sonography with application of 2DST seems to be a good candidate for comprehensive evaluation of atherosclerosis in families with FH.

A low threshold for neonatal intervention yields a high rate of biventricular outcomes in pulmonary atresia with intact ventricular septum.

AIMS: Management strategies for pulmonary atresia with intact ventricular septum are variable and are based on right ventricular morphology and associated abnormalities. Catheter perforation of the pulmonary valve provides an alternative strategy to surgery in the neonatal period. We sought to assess the long-term outcome in terms of survival, re-intervention, and functional ventricular outcome in the setting of a 26-year single-centre experience of low threshold inclusion criteria for percutaneous valvotomy. METHODS AND RESULTS: Retrospective analysis of patients diagnosed with pulmonary atresia with intact ventricular septum from 1990 to 2016 at a tertiary referral centre, was performed. Of 71 patients, 48 were brought to the catheterisation laboratory for intervention. Catheter valvotomy was successful in 45 patients (94%). Twenty-three patients (51%) also underwent ductus arteriosus stenting. The length of intensive care and hospital stay was significantly shorter, and early re-interventions were significantly reduced in the catheterisation group. There were eight deaths (17%); all within 35 days of the procedure. Of the survivors, only one has required a Fontan circulation. Twenty-eight patients (74%) have undergone biventricular repair and nine patients (24%) have one-and-a-half ventricle circulation. Following successful valvotomy, 80% of patients required further catheter-based or surgical interventions. CONCLUSIONS: A low threshold for initial interventional management yielded a high rate of successful biventricular circulations. Although mortality was low in patients who survived the peri-procedural period, the rate of re-intervention remained high in all groups.

Giving up knowledge is almost never a good idea: an interview with Dr Evan Zahn.

The history of congenital interventional cardiology has seen numerous groundbreaking innovations typically related to the introduction of a new device or a novel treatment technique. Similarly, imaging of cardiac defects has changed dramatically over the past decades, although some of the advancements have seemed to omit the catheterisation laboratories. Rotational angiography, one of the imaging techniques for guidance of cardiac catheterisation currently referred to as "advanced", in fact was described already in 1960s.1 More recently its improved version, including three-dimensional reconstruction (3DRA), became a valuable intra-procedural imaging tool in interventional cardiology and neuroradiology.2 Dr Evan Zahn was one of the pioneers of 3DRA in the field of congenital cardiology, setting an example for many to follow. With his innovative publication and subsequent lecture at 2011 Pediatric and Adult Interventional Cardiac Symposium (PICS-AICS) on "The Emerging Use of 3-Dimensional Rotational Angiography in Congenital Heart Disease" he motivated many to explore benefits of this modality to strive for improved procedural outcomes and reduced patients' burden of cardiac catheterisation3. I was one of those to take Dr Zahn's thoughts and implement them into routine workflow.4-6 However, almost a decade after Dr Zahn shared his important work, despite tremendous efforts by teams from Utrecht, (Netherlands) and Columbus (Ohio, United States of America) to popularise 3D imaging in catheterisation laboratory during dedicated meetings, two-dimensional (2D) angiography does not seem to be threatened in many, otherwise-progressive, laboratories. During the recent 30th Japanese Pediatric Interventional Cardiology (JPIC) meeting I had the opportunity to ask Dr Zahn why giving up knowledge is almost never a good idea, what is technology's natural order of things, and why the technology has to be more than just exciting, pretty, and new.

Accessing extracorporeal membrane oxygenation circuits to perform emergent interventional cardiac catheterisation.

Cardiac catheterisation in patients on extracorporeal membrane oxygenation (ECMO) may reveal new information leading to modification of a therapeutic plan and correction of newly recognised or residual lesions. Complications associated with cardiac catheterisation during ECMO are not uncommon and often related to the access site. We report a straightforward technique for accessing the ECMO circuit to perform an emergent cardiac catheterisation in two patients with hypoplastic left heart syndrome decompensated after Norwood I, due to presumed systemic-to-pulmonary artery shunt obstruction.

Multimodality imaging for no contrast trans-catheter closure of an arteriovenous fistula.

A 6-year-old patient was diagnosed with an arteriovenous fistula in the neck region. Non-invasive three-dimensional imaging, including computed tomography and ultrasonography, was used for guidance of percutaneous closure of the fistula and evaluation of the final outcome.

Molding the shape of congenial and structural interventional cardiology: interviews with directors of major congresses.

The range and number of educational and networking events that are available for fellows, trainees, and junior faculty to attend grows every year. Each meeting useful in its own way; each adding value to the development and the growth of an interventionist. Within paediatric, congenital, and structural heart disease, three of the standout meetings are: Pediatric and Interventional Cardiac Symposium (PICS-AICS), Congenital and Structural Interventions (CSI), and International Workshop on Interventional Pediatric and Adult Congenital Cardiology (IPC). All of these were started by leaders in our field; people known to be passionate educators and innovators. International congresses focusing more broadly on congenital cardiac disease in children and adults are rare. These forums allow more interdisciplinary discussions between the interventionist, surgeon, and non-invasive specialists. Purely interventional meetings are essential to allow colleagues to debate and explore the nuances and intricacies of technique and approach, developing concepts to be challenged in wider forums. During the recent 21st PICS-AICS meeting Prof. Ziyad M. Hijazi, Shakeel A. Qureshi, Mario Carminati, and Dr Damien Kenny shared their time to engage in frank, recorded conversations which provide a unique insight in to the process and concepts behind three of our most important educational congresses.

Stenting of the inter-atrial septum in infants and small children: Indications, techniques and outcomes.

OBJECTIVES: To evaluate the procedural success and outcome of inter-atrial stenting. BACKGROUND: Inter-atrial stenting has been shown to be an effective way to maintain inter-atrial blood flow, however it is considered a high risk procedure, usually performed urgently in patients with significant hemodynamic compromise. METHODS: Between September 2004 and August 2016, inter-atrial stenting was attempted in 29 children. Procedural, clinical, and follow-up data were collected retrospectively. RESULTS: The procedures were completed successfully in 27 patients. Twenty-five procedures were undertaken percutaneously, with the remaining four being performed as hybrid procedures. The patients were considered as high risk for adverse events (82% scored as CRISP 4 and 5) with four deaths during the first 24 hr (14%). Procedural complications occurred in eight patients (28%) with related death in three patients (10%). One further patient died after an uncomplicated technically successful stent implantation performed as a salvage procedure. Procedural complications (71% vs. 14%) and mortality (43% vs. 5%) were higher in those, who weighed 3 kg or less (P < 0.05). Patency of the stents was maintained until planned staged surgery in 22 patients at a mean of 302 days. Three patients underwent further balloon dilation for flow restriction at 58-201 days. In two un-operated patients the stents remained patent at follow-up. One patient with severe pulmonary hypertension died with a patent stent. CONCLUSIONS: Inter-atrial stenting produces reliable patency with a very good success rate. Morbidity and mortality were related to low weight at the time of the procedure.

Catheter, MRI and CT Imaging in Newborns with Pulmonary Atresia with Ventricular Septal Defect and Aortopulmonary Collaterals: Quantifying the Risks of Radiation Dose and Anaesthetic Time.

A comprehensive understanding of the native pulmonary blood supply is crucial in newborns with pulmonary atresia with ventricular septal defect and aortopulmonary collaterals (PA/VSD/MAPCA). We sought to describe the accuracy in terms of identifying native pulmonary arteries, radiation dose and anaesthetic time associated with multi-modality imaging in these patients, prior to their first therapeutic intervention. Furthermore, we wanted to evaluate the cumulative radiations dose and anaesthetic time over the study period. Patients with PA/VSD/MAPCA diagnosed at < 100 days between 2004 and 2014 were identified. Cumulative radiation dose and anaesthetic times were calculated, with imaging results compared with intraoperative findings. We then calculated the cumulative risks to date for all surviving children. Of 19 eligible patients, 2 had echocardiography only prior to first intervention. The remaining 17 patients underwent 13 MRIs, 4 CT scans and 13 cardiac catheterization procedures. The mean radiation dose was 169 mGy cm2 (47-461 mGy cm2), and mean anaesthetic time was 111 min (33-185 min). 3 children had MRI only with no radiation exposure, and one child had CT only with no anaesthetic. Early cross-sectional imaging allowed for delayed catheterisation, but without significantly reducing radiation burden or anaesthetic time. The maximum cumulative radiation dose was 8022 mGy cm2 in a 6-year-old patient and 1263 min of anaesthetic at 5 years. There is the potential to generate very high radiation doses and anaesthetic times from diagnostic imaging alone in these patients. As survival continues to improve in many congenital heart defects, the important risks of serial diagnostic imaging must be considered when planning long-term management.

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.

Novel Three-Dimensional Image Fusion Software to Facilitate Guidance of Complex Cardiac Catheterization : 3D image fusion for interventions in CHD.

We report initial experience with novel three-dimensional (3D) image fusion software for guidance of transcatheter interventions in congenital heart disease. Developments in fusion imaging have facilitated the integration of 3D roadmaps from computed tomography or magnetic resonance imaging datasets. The latest software allows live fusion of two-dimensional (2D) fluoroscopy with pre-registered 3D roadmaps. We reviewed all cardiac catheterizations guided with this software (Philips VesselNavigator). Pre-catheterization imaging and catheterization data were collected focusing on fusion of 3D roadmap, intervention guidance, contrast and radiation exposure. From 09/2015 until 06/2016, VesselNavigator was applied in 34 patients for guidance (n = 28) or planning (n = 6) of cardiac catheterization. In all 28 patients successful 2D-3D registration was performed. Bony structures combined with the cardiovascular silhouette were used for fusion in 26 patients (93%), calcifications in 9 (32%), previously implanted devices in 8 (29%) and low-volume contrast injection in 7 patients (25%). Accurate initial 3D roadmap alignment was achieved in 25 patients (89%). Six patients (22%) required realignment during the procedure due to distortion of the anatomy after introduction of stiff equipment. Overall, VesselNavigator was applied successfully in 27 patients (96%) without any complications related to 3D image overlay. VesselNavigator was useful in guidance of nearly all of cardiac catheterizations. The combination of anatomical markers and low-volume contrast injections allowed reliable 2D-3D registration in the vast majority of patients.

Stent implantation to ductus arteriosus in a patient with interrupted aortic arch guided by CT image overlay.

A 15-day-old premature patient with ventricular septal defect and interrupted aortic arch type B underwent "hybrid" initial treatment consisting of bilateral pulmonary artery banding followed by stenting of the ductus arteriosus. A pre-registered CT scan was re-purposed with a new three-dimensional image fusion software (VesselNavigator) to create a roadmap for stent delivery.

Comparison of self-expandable and balloon-expanding stents for hybrid ductal stenting in hypoplastic left heart complex.

OBJECTIVES: We aimed to compare the procedural and mid-term performance of a specifically designed self-expanding stent with balloon-expandable stents in patients undergoing hybrid palliation for hypoplastic left heart syndrome and its variants. BACKGROUND: The lack of specifically designed stents has led to off-label use of coronary, biliary, or peripheral stents in the neonatal ductus arteriosus. Recently, a self-expanding stent, specifically designed for use in hypoplastic left heart syndrome, has become available. METHODS: We carried out a retrospective cohort comparison of 69 neonates who underwent hybrid ductal stenting with balloon-expandable and self-expanding stents from December, 2005 to July, 2014. RESULTS: In total, 43 balloon-expandable stents were implanted in 41 neonates and more recently 47 self-expanding stents in 28 neonates. In the balloon-expandable stents group, stent-related complications occurred in nine patients (22%), compared with one patient in the self-expanding stent group (4%). During follow-up, percutaneous re-intervention related to the ductal stent was performed in five patients (17%) in the balloon-expandable stent group and seven patients (28%) in self-expanding stents group. CONCLUSIONS: Hybrid ductal stenting with self-expanding stents produced favourable results when compared with the results obtained with balloon-expandable stents. Immediate additional interventions and follow-up re-interventions were similar in both groups with complications more common in those with balloon-expandable stents.

Use of pre-intervention imaging with a novel image fusion software for guidance of cardiac catheterisation in a patient with pulmonary atresia and major aortopulmonary collaterals.

We present a 3.5-year-old patient with tetralogy of Fallot, pulmonary atresia, and major aortopulmonary collaterals, after repeat implantation of a central shunt, in whom we successfully re-purposed previous imaging scans with a novel image fusion software to guide diagnostic heart catheterisation. The pre-registered CT scan was segmented before the procedure and subsequently manually fused with two-dimensional fluoroscopy images. The overlaid roadmap enhanced selective cannulation of all major vessels originating from the aorta, making aortography unnecessary.