Early Infective Endocarditis Associated with an Amplatzer Atrial Septal Occluder Device in a 14-Year-Old Male.

Infective endocarditis (IE) associated with an ASD device, particularly in the early post-procedure period, is extremely rare. We report a case of infective endocarditis presenting with embolic complications and vegetations on the device that were only seen on transesophageal echocardiography, necessitating device removal.

Correlation between non-invasive to invasive right-heart data in paediatric heart transplant patients.

BACKGROUND: Paediatric studies have shown serum N-terminal pro b-type natriuretic peptide levels to be a valuable tool in the surveillance of myocardial function and an early biomarker for rejection in transplant patients. The correlation between low mean right atrial pressure and increased inferior vena cava collapsibility index is well studied in adults. Our study aims to assess correlation between non-invasive measurements (serum N-terminal pro b-type natriuretic peptide, inferior vena cava dimensions collapsibility, tricuspid regurgitation, and left ventricular remodelling index to invasive mean right atrial pressure in paediatric heart transplant patients). METHODS: A single centre, retrospective chart review of the paediatric transplant patients from 0 to 21 years of age was performed between 2015 and 2017. Thirty-nine patients had complete data which includes cardiac catheterisation, transthoracic echocardiogram, and serum N-terminal pro b-type natriuretic peptide levels done within a two weeks of interval. RESULTS: A higher inferior vena cava collapsibility index correlated with a lower mean right atrial pressure (r = -0.21, p = 0.04) and a larger inferior vena cava diameter in expiration indexed to body surface area (IVCmax/BSA0.5) correlated with a higher mean right atrial pressure (r = 0.29, p = 0.01). There was a correlation between elevated N-terminal pro b-type natriuretic peptide and inferior vena cava collapsibility index (r = -0.38, p = 0.0001), IVCmax/BSA0.5 (r = 0.25, p = 0.0002), and mean right atrial pressure (r = 0.6, p = 0.0001). CONCLUSION: Serum N-terminal pro b-type natriuretic peptide levels correlated to non-invasive measurements (inferior vena cava collapsibility index and IVCmax/BSA0.5) and to the invasive mean right atrial pressure. Non-invasive (IVC-CI IVCmax/BSA0.5) correlates with elevated mean right atrial pressure in this population. Together, these may serve as a reliable surveillance tool in assessing right heart filling pressures and cardiac function within the paediatric heart transplant patient.

Is derived vectorcardiography a potential screening tool for pulmonary hypertension?

BACKGROUND: Patients with atrial septal defects and pulmonary hypertension would benefit from early identification and treatment of pulmonary hypertension prior to closure. Noninvasive screening tools for pulmonary hypertension are inadequate. Electrocardiography, though readily available, has so far been of limited screening utility in patients with pulmonary hypertension. We hypothesize that derived vectorcardiographic parameters will aid in identifying increased right ventricular afterload and thus provide an additional screening tool for pulmonary hypertension in patients with secundum atrial septal defects. OBJECTIVE: Establish whether vectorcardiography can be used to screen for pulmonary hypertension. METHODS: A retrospective review of patients with secundum atrial septal defects (ASD) who underwent cardiac catheterization at the University of Minnesota from 2012 to 2020 was performed. We excluded patients with other congenital heart diagnoses, insufficient hemodynamic data, or lacking sinus rhythm electrocardiogram at time of cardiac catheterization. Parameters analyzed included: Sokolow-Lion right ventricular hypertrophy criteria, PR duration, QRS duration, corrected QT intervals, QRS and T wave frontal plane axes, rSR', R' amplitude, as well as vectorcardiographic parameters (Kors regression-related method), the QRS vector magnitude, T wave vector magnitude, and the spatial QRS-T angle. These were compared to measures of pulmonary hypertension obtained at cardiac catheterization. RESULTS: The spatial QRS-T angle significantly differentiated ASD patients with pulmonary hypertension (median 104 degrees, interquartile range 55-137 degrees) from ASD patients without pulmonary hypertension (median 37 degrees, interquartile range 21-63 degrees, p-value of 0.002). At a cut-off of 124 degrees, the positive and negative predictive values for identification of pulmonary hypertension were 36.4% and 96.4%, respectively, with an odds ratio of 13.4 (95% confidence interval of 2.9 to 63.7). The positive predictive value was significantly improved when combined with echocardiographic data to screen for pulmonary hypertension. CONCLUSION: The spatial QRS-T angle is associated with pulmonary hypertension in patients with secundum atrial septal defects.

Successful rapid staged hybrid approach for obstructed total anomalous pulmonary venous connection.

Obstructed total anomalous pulmonary venous connection (TAPVC) represents a true pediatric cardiac emergency. The patient may present in extremis secondary to severe pulmonary hypertension and cardiogenic shock which increases perioperative mortality. We present a neonate who underwent a successful staged hybrid approach for an Infradiaphragmatic obstructed TAPVC.

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.

Pediatric SubQ-ICD implantation, a single center review of the inter-muscular technique.

INTRODUCTION: Pediatric patients with cardiomyopathies are at risk for sudden death and may need implantable cardioverter defibrillators (ICD's), but given their small size and duration of use, children are at increased risk for complications associated with ICD use. The subcutaneous ICD presents a favorable option for children without pacing indications. Unfortunately, initial pediatric studies have demonstrated a high complication rate, likely due to the 3-incision technique employed. MATERIAL AND METHODS: Patients with ICD but no pacing indication were retrospectively reviewed after implantation of subcutaneous ICD via the two-incision technique. In half of the patients, 10-J impedance test was also performed to compare with impedance obtained after defibrillation threshold testing with 65-J. RESULTS: Twelve patients were included. The median age was 14 years (range 10-16 years) with eight males included (72.7%). The median weight was 55 kg (range 29 kg-75.1 kg). Follow-up had a median of 11.5 months (range 2-27 months). The median body mass index was 18.4 kg/m squared (range 15.5-27.9 kg/m squared). One patient suffered a minor complication after tearing off the incisional adhesive strips early and required a non-invasive repair in clinic. Shock impedance had a median of 55 J (range 48-68 J). There was one appropriate shock/charge and no inappropriate shocks during follow-up. CONCLUSION: The two-incision, intermuscular technique appears to have a lower acute complication rate than prior reports, in our cohort of 12 pediatric patients.

Balloon expandable covered stents as primary therapy for hemodynamically stable traumatic aortic injuries in children.

OBJECTIVES: To expand on the limited available literature regarding the use of balloon expandable covered stents for the treatment of traumatic aortic injuries (TAI) in the pediatric population. BACKGROUND: Although endovascular grafts have largely replaced surgery for TAI repair, there are significant limitations to the use of these grafts in pediatric patients. METHODS: Multicenter, retrospective chart review of pediatric patients with TAI following blunt chest wall trauma. Procedural characteristics, follow-up, and reinterventions are described. RESULTS: Six covered stents implanted in five patients. Median patient age was 12 years (11-13 years) and median weight 50 kg (44-54 kg). Procedural success was achieved in all cases. No procedural or postprocedural complications were noted. Median follow-up time was 24 months (11-36 months). CONCLUSIONS: Balloon expandable covered stent treatment of pediatric patients with TAI is a feasible alternative to open surgical repair, and preferred over endovascular grafts due to graft size limitations and the large delivery systems.

Acute and medium term results of balloon expandable stent placement in the transverse arch-a multicenter pediatric interventional cardiology early career society study.

OBJECTIVES AND BACKGROUND: Coarctation of the aorta represents 5-8% of all congenital heart disease. Although balloon expandable stents provide an established treatment option for native or recurrent coarctation, outcomes from transverse arch (TAO) stenting, including resolution of hypertension have not been well studied. This study aims to evaluate immediate and midterm results of TAO stenting in a multi-center retrospective cohort. METHODS: TAO stenting was defined as stent placement traversing any head and neck vessel, with the primary intention of treating narrowing in the transverse aorta. Procedural details, complications and medications were assessed immediately post procedure, at 6 month follow-up and at most recent follow-up. RESULTS: Fifty-seven subjects, 12 (21%) native, and 45 (79%) surgically repaired aortic arches, from seven centers were included. Median age was 14 years (4 days-42 years), median weight 54 kg (1.1-141 kg). After intervention, the median directly measured arch gradient decreased from 20 mmHg (0-57 mmHg) to 0 mmHg (0-23 mmHg) (p < .001). The narrowest arch diameter increased from 9 mm (1.4-16 mm) to 14 mm (2.9-25 mm) (p < .001), with a median increase of 4.9 mm (1.1-10.1 mm). One or more arch branches were covered by the stent in 55 patients (96%). There were no serious adverse events. Two patients warranted stent repositioning following migration during deployment. There were no late complications. There were 8 reinterventions, 7 planned, and 1 unplanned (6 catheterizations, 2 surgeries). Antihypertensive management was continued in 19 (40%) at a median follow-up of 3.2 years (0.4-7.3 years). CONCLUSIONS: TAO stenting can be useful in selected patients for resolution of stenosis with minimal complications. This subset of patients are likely to continue on antihypertensive medications despite resolution of stenosis.

Effects of Systemic Steroid Administration on Recurrence of Pericardial Effusion in Pediatric Patients After Hematopoietic Stem Cell Transplantation.

Although rare in the general pediatric population, the incidence of pericardial effusion is significantly higher in pediatric patients undergoing hematopoietic stem cell transplant (HCT) with a reported incidence of up to 16.9%. The development of pericardial effusion in this setting is associated with higher mortality. Although pericardiocentesis is a relatively safe procedure for treating pericardial effusion, it is invasive, painful, and exposes an immunosuppressed patient to the risks of infection, bleeding, and injury to surrounding structures. Given the procedural risks of pericardiocentesis, systemic steroids are often administered for the treatment of pericardial effusion given their use for pericarditis in the general population. However, the effectiveness of systemic steroids for the treatment of pericardial effusion in the pediatric HCT population has not been confirmed. We studied the role of systemic steroids, administered at the time of initial pericardiocentesis performed for pericardial effusion, in preventing repeat pericardiocentesis. A total of 37 pericardiocenteses after HCT were performed during the study period with 25 patients undergoing first-time pericardiocentesis and 15 of those patients receiving systemic steroids. Eight patients required repeat pericardiocentesis; 5 of 15 (33%) received steroids and 3 of 10 (30%) did not receive steroids. Our data in this small cohort of pediatric HCT patients did not show a significant difference in the need for repeat pericardiocentesis with the use of systemic steroids, initiated within 48 hours of pericardiocentesis.

Echocardiographic imaging of the Medtronic Micro Vascular Plug™ during off label placement in the premature infant with patent ductus arteriosus.

OBJECTIVES: To report the usefulness of harmonic imaging in echocardiography to visualize and direct the implantation of the Medtronic micro vascular plug (MVP). BACKGROUND: Off label use of the MVP was reported for transcatheter occlusion of patent ductus arteriosus (PDA) in premature infants. The device is poorly visible on fluoroscopy and echocardiography. METHODS: In 9 consecutive premature infants, the MVP was used for transcatheter closure of the PDA. In each, the ability of conventional echocardiographic imaging was compared to harmonic imaging, and the device was deployed in the PDA using echocardiography. RESULTS: In each subject, harmonic imaging proved superior to conventional echocardiography to visualize the MVP in premature infants using 12 and 8 MHz probes. Once the delivery, catheter was across the PDA into the descending aorta, and the MVP advanced to the catheter tip, positioning, and deployment of the device was possible without fluoroscopy. All devices were deployed appropriately with immediate occlusion and no obstruction to the left pulmonary artery or aorta. CONCLUSIONS: The MVP can be accurately imaged using harmonic imaging, even in the near field in premature infants. Precise implantation of the MVP in the PDA of premature infants is possible with echocardiographic imaging of the device and vascular structures.

How Slow Can We Go? 4 Frames Per Second (fps) Versus 7.5 fps Fluoroscopy for Atrial Septal Defects (ASDs) Device Closure.

Radiation exposure remains a significant concern for ASD device closure. In an effort to reduce radiation exposure, the default fluoroscopy frame rate in our Siemens biplane pediatric catheterization laboratory was reduced to 4 fps in November 2013 from an earlier 7.5 fps fluoro rate. This study aims to evaluate the components contributing to total radiation exposure and compare the procedural success and radiation exposure during ASD device closure using 4 versus 7.5 fps fluoroscopy rates. Twenty ASD device closures performed using 4 fps fluoro rate were weight-matched to 20 ASD closure procedures using 7.5 fps fluoro rate. Baseline characteristics, procedure times and case times were similar in the two groups. Device closure was successful in all but one case in the 4 fps group. The dose area product (DAP), normalized DAP to body weight, total radiation time and fluoro time were lower in the 4 fps group but not statistically different than the 7.5 fps. The number of cine images and cine times were identical in both groups. Fluoroscopy and cineangiography contributed equally to radiation exposure. Fluoroscopy at 4 fps can be safe and effective for ASD device closure in children and adults. There was no increase in procedure time, cine time, fluoro time or complications at this slow fluoro rate. There was a trend toward decreased radiation exposure as measured by indexed DAP although not statistically significant in this small study. Further study with multiple operators using 4 fps fluoroscopy for simple interventional procedures is recommended.

Verapamil-sensitive idiopathic left ventricular tachycardia in a 6-month-old: unique considerations in diagnosis and management in an infant.

Idiopathic left ventricular tachycardia of the Belhassen type is rare in infants. We present a 6-month-old infant girl with a wide-complex tachycardia with right bundle branch block QRS morphology, a superior axis, and atrioventricular dissociation, consistent with a left anterior fascicular tachycardia. Initial echocardiogram revealed depressed ventricular function. The tachycardia was unresponsive to therapeutic trials of adenosine, esmolol, procainamide, and lidocaine. There was brief conversion of the tachycardia to sinus rhythm with transesophageal atrial overdrive pacing, suggesting a reentrant mechanism of the arrhythmia. Ultimately, the judicious administration of intravenous verapamil resulted in termination of the arrhythmia, which has been sustained on oral therapy.

Transcatheter closure of a large post-myocardial infarction ventricular septal defect using the GORE cardioform ASD Occluder.

A 49-year-old man presented late with an anterior wall myocardial infarction (MI) status post-primary coronary intervention of the left anterior descending artery that resulted in no reflow of the vessel. The patient was transferred to our institution in cardiogenic shock.

Early Concerning Outcomes for the Edwards Inspiris Resilia Bioprosthesis in the Pulmonary Position.

BACKGROUND: The Inspiris Resilia (Edwards Lifesciences LLC) bioprosthesis has gained widespread use in the aortic position; however no robust data are available about its use in the pulmonary position. METHODS: We reviewed our outcomes for the Inspiris Resilia in the pulmonary position between August 2019 and October 2021. RESULTS: Twenty-seven patients (15 female patients [56%]; mean age, 22.26 ± 14.99 years) were included. The most common original pathology was tetralogy of Fallot (13 patients, 48%). Five patients (18.5%) had prior transcatheter interventions. The mean right ventricular end-diastolic volume index was 164.25 ± 45.1 mL/m2. Sternotomy or repeat sternotomy was the most common approach (21 patients, 77.8%). The standard technique for pulmonary valve replacement was used in 22 patients (81.5%), whereas the prosthesis was implanted as a conduit in the remaining 5 (18.5%). Trivial to mild prosthetic regurgitation was present in 6 patients (22.2%) at the time of discharge. There was no early mortality. Follow-up was complete in all patients (mean, 16 ± 8 months), with no late mortality or late reoperations. New prosthetic regurgitation developed in 13 patients (48%), all of whom underwent replacement with the standard surgical technique. No regurgitation occurred in the conduit cases. This progressed to moderate regurgitation in 6 patients (22%) and severe in 3 (11%). Three patients (11%) underwent transcatheter valve-in-valve after their surgical pulmonary valve replacement. CONCLUSIONS: The early data regarding the Inspiris Resilia bioprosthesis use in the pulmonary position is concerning. The prosthesis design may not be suitable for low-pressure circulation, or modification of its implantation technique may be needed.

Invasive Right Ventricular Pressure-Volume Analysis: Basic Principles, Clinical Applications, and Practical Recommendations.

Right ventricular pressure-volume (PV) analysis characterizes ventricular systolic and diastolic properties independent of loading conditions like volume status and afterload. While long-considered the gold-standard method for quantifying myocardial chamber performance, it was traditionally only performed in highly specialized research settings. With recent advances in catheter technology and more sophisticated approaches to analyze PV data, it is now more commonly used in a variety of clinical and research settings. Herein, we review the basic techniques for PV loop measurement, analysis, and interpretation with the aim of providing readers with a deeper understanding of the strengths and limitations of PV analysis. In the second half of the review, we detail key scenarios in which right ventricular PV analysis has influenced our understanding of clinically relevant topics and where the technique can be applied to resolve additional areas of uncertainty. All told, PV analysis has an important role in advancing our understanding of right ventricular physiology and its contribution to cardiovascular function in health and disease.

Intraoperative fluorescence with indocyanine green in congenital cardiac surgery: Potential applications of a novel technology.

BACKGROUND: Achieving successful repair of congenital heart defects requires attention to detail. Careful evaluation of anastomotic site patency, reimplanted coronary arteries, location of epicardial coronaries, and myocardial perfusion may be necessary to ensure safe conduct of the operation and achieve excellent outcomes. METHODS: Intraoperative fluorescence angiography (IOFA) was performed using indocyanine green in patients undergoing the following procedures: coronary artery reimplantation, coronary artery unroofing, evaluation of intraoperative coronary anatomy, reoperation requiring ventriculotomy, coarctation/interrupted aortic arch repair, systemic-to-pulmonary artery shunt, Norwood procedure, thoracic duct localization, and vascular rings. RESULTS: The technique was feasible in all patients. No mortality or adverse events related to the dye were encountered. Adequate intraoperative imaging was obtained in 15 patients (20 images), which correlated well with postoperative studies. The imaging quality was superior for assessing shunt patency, myocardial perfusion, and anastomotic patency and determining the location of epicardial coronary arteries but was less so for assessing branch pulmonary arteries. CONCLUSIONS: IOFA is a useful and safe technique that can provide a quick on-table assessment of a variety of congenital surgical procedures. This may help answer questions that can minimize postoperative interventions and help ensure a smooth perioperative course and excellent outcomes.

Unroofing of Myocardial Bridging After Septal Myectomy in a Child With Noonan Syndrome.

Myocardial bridging is a controversial topic that remained with no well-defined management protocol. We present a ten-year-old child with Noonan syndrome and a myocardial bridge.

Treatment approach to unilateral branch pulmonary artery stenosis.

Unilateral proximal pulmonary artery stenosis is often seen in the setting of postoperative congenital heart disease. Accurate assessment of the hemodynamic significance of such a lesion is important so as to determine "When to intervene?" A thorough evaluation should include symptom assessment, anatomical assessment through detailed imaging, functional assessment using differential pulmonary blood flow measurement and cardiopulmonary exercise testing. Symptoms of exertional dyspnea or intolerance, decreased pulmonary blood flow to stenosed lung, and abnormal exertional performance would be factors to pursue therapy in the setting of significant anatomical narrowing. Safe and effective therapy can be offered through transcatheter or surgical techniques and has been shown to improve exertional performance.