Pediatric cardiac interventions

Infrared thermography as an adjunctive tool for detection of femoral arterial thrombosis after cardiac catheterization: A prospective, pilot study

OBJECTIVES

To assess the utility of infrared thermography (IRT), to map skin temperature, in the detection of femoral arterial (FA) thrombosis after cardiac catheterization.

BACKGROUND

Ultrasound is a validated method for thrombus detection but is generally reserved as a confirmatory test for clinical suspicion due to various constraints.

METHODS

Prospective study of infants and children undergoing cardiac catheterization via FA access, comparing IRT and pulse examination. The thermograms, displayed in a color map with each pixel representing a temperature, were examined by qualitative assessment of symmetry in thermal patterns and quantitative image analysis with abnormal thermographic asymmetry defined as a difference of >10% between limbs.

RESULTS

In the 20 children enrolled, excellent agreement was found between the two methods with a Kappa value of 0.89. The median thermographic asymmetry in the nine children with pulse loss was 36 (13-76)%. Using receiver operating characteristic analysis, the asymmetrical pattern of ≥18% between limbs predicted the need for anticoagulation with a sensitivity of 100% and specificity of 89%. The area under the curve was 0.97 (95% confidence interval: 0.95-1). Children with absent pulse requiring anticoagulation showed a slower recovery in thermal asymmetry compared to those with a reduced pulse. By qualitative IRT assessment, all children with absent pulse requiring anticoagulation were correctly identified by 10 independent assessors.

CONCLUSIONS

This pilot study showed that IRT is feasible and reliable as an adjunctive tool for thrombus detection postcatheterization and treatment monitoring. Specific advantages of IRT include portability, affordability, and contactless image acquisition.

The Future of Paediatric Heart Interventions: Where Will We Be in 2030?

Purpose of Review

Cardiac catheterization therapies to treat or palliate infants, children and adults with congenital heart disease have developed rapidly worldwide in both technical innovation and device development in the previous three decades. By reviewing of current status of novel or development of devices and techniques, we will discuss what is likely to happen in paediatric heart intervention in the next decade.

Recent Findings

Recently, biodegradable stents and devices, transcatheter pulmonary valve implantation for the native right ventricle outflow tract and MRI-guided interventions have been progressing rapidly with good immediate to early results. These are expected to be introduced and spread in the next decade although there are still challenges to overcome.

Summary

The future of paediatric heart intervention is very promising with rapid development of technological progress.

Pediatric Cardiac MR Imaging:: Practical Preoperative Assessment

Prevalence of patients with congenital heart disease (CHD) is rapidly increasing due to continuous advancements in diagnostic techniques and medical or surgical treatment approaches. Along with cardiac computed tomography angiography, cardiac magnetic resonance (CMR) serves as a fundamental imaging modality for pre-surgical planning in patients with CHD, as CMR allows for the evaluation of cardiac and great vessel anatomy, biventricular function, flow dynamics, and tissue characterization. This information is essential for risk-assessment and optimal timing of surgical interventions. This article discusses the current role of pediatric cardiac MR imaging as a practical preoperative assessment tool in the pediatric population.

Current Transcatheter Approaches for the Treatment of Aortic Coarctation in Children and Adults

Coarctation of the aorta is a common congenital heart defect and can present at any age. Infants may carry a fetal diagnosis, or are generally diagnosed after auscultation of a murmur, although rarely present in shock. Those that escape early childhood detection typically present in adolescence and adulthood, generally with upper-extremity hypertension. Percutaneous therapies have evolved to include balloon angioplasty and stent placement, and generally are the preferred first-line therapy for most adolescent/adult patients. Percutaneous interventions are now viable options in younger and smaller patients. The advent of bioresorbable stents may provide further expansion of treatment options to very small patients.

Towards the definition of Institutional diagnostic reference levels in paediatric interventional cardiology procedures in Greece

This study aimed to evaluate paediatric radiation doses in a dedicated cardiology hospital, with the objective of characterising patterns in dose variation. The ultimate purpose was to define Local (Institutional) Diagnostic Reference Levels (LDRLs) for different types of paediatric cardiac interventional procedures (IC), according to patient age. From a total of 710 cases performed during three consecutive years, by operators with more than 15 years of experience, the age was noted in only 477 IC procedures. The median values obtained for Fluoroscopy Time (FT), Number of Frames (N) and Kerma Area Product (P_KA) by age range were 5.8 min, 1322 and 2.0 Gy.cm² for <1 y; 6.5 min, 1403 and 3.0 Gy.cm² for 1 to <5 y; 5.9 min, 950 and 7.0 Gy.cm² for 5 to <10 y; 5.7 min, 940 and 14.0 Gy.cm² for 10 to <16 y, respectively. A large range of patient dose data is observed, depending greatly on procedure type and patient age. In all age groups the range of median FT, N and P_KA values was 3.1-15.8 min, 579-1779 and 1.0-20.8 Gy.cm² respectively. Consequently, the definition of LDRLs presents challenges mainly due to the multiple clinical and technical factors affecting the outcome. On the other hand the lack of paediatric IC DRLs makes the identification of good practices more difficult. A consensus is needed on IC procedures nomenclature and grouping in order to allow a common assessment and comparison of doses.

Organ doses in pediatric patients undergoing cardiac-centered fluoroscopically guided interventions: Comparison of three methods for computational phantom alignment

PURPOSE

To assess various computational phantom alignment techniques within Monte Carlo radiation transport models of pediatric fluoroscopically guided cardiac interventional studies.

METHODS

Logfiles, including all procedure radiation and machine data, were extracted from a Toshiba infinix-I unit in the University of Florida Pediatric Catheterization Laboratory for a cohort of 10 patients. Two different alignment methods were then tested against a ground truth standard based upon identification of a unique anatomic reference point within images co-registered to specific irradiation events within each procedure. The first alignment method required measurement of the distance from the edge of the exam table to the top of the patient's head (table alignment method). The second alignment method fixed the anatomic reference point to be the geometric center of the heart muscle, as all 10 studies were cardiac in nature. Monte Carlo radiation transport simulations were performed for each patient and intervention using morphometry-matched hybrid computational phantoms for the reference and two tested alignment methods. For each combination, absorbed doses were computed for 28 organs and root mean square organ doses were assessed and compared across the alignment methods.

RESULTS

The percent error in root mean square organ dose ranged from -57% to +41% for the table alignment method, and from -27% to +22% for the heart geometric centroid alignment method. Absorbed doses to specific organs, such as the heart and lungs, demonstrated higher accuracy in the heart geometric centroid alignment method, with average percent errors of 10% and 1.4%, respectively, compared to average percent errors of -32% and 24%, respectively, using the table alignment method.

CONCLUSIONS

Of the two phantom alignment methods investigated in this study, the use of an anatomical reference point - in this case the geometric centroid of the heart - provided a reliable method for radiation transport simulations of organ dose in pediatric interventional cardiac studies. This alignment method provides the added benefit of requiring no physician input, making retrospective calculations possible. Moving forward, additional anatomical reference methods can be tested to assess the reliability of anatomical reference points beyond cardiac centered procedures.

Landmark lecture on interventional cardiology: interventional cardiac catheterisation for CHD: the past, present, and the future

CHD affects millions of patients worldwide. Interventional therapies for CHD goes back to the mid-1960s when Bill Rashkind performed balloon atrial septostomy on a cyanotic baby with transposition of the great vessels. This was followed by development of balloon catheters to perform balloon valvuloplasties and angioplasties in the early to late 1980s. Although King and Mills performed the first transcatheter closure of secundum atrial septal defect in the mid-1970s, this procedure was better realised in the mid-1990s. More intracardiac defect closures were performed in the late 1990s and early 2000. This brings us to the current era of percutaneous valve implantation as developed by Bonhoeffer. In this paper, we will discuss the past, present, and future of interventional cardiac catheterisation for CHD patients.

CHARACTERIZATION AND EXPERIMENTAL MEASUREMENTS OF SCATTER DOSE AT CARDIOLOGIST'S EYES DURING PAEDIATRIC INTERVENTIONAL CARDIOLOGY PROCEDURES IN COSTA RICA

This paper presents the results of the first characterization and experimental measurements of scatter dose at cardiologist's eyes for the only X-ray system that performs all paediatric Interventional cardiology procedures in Costa Rica. Entrance surface air kerma (ESAK) and the scatter dose values were measured on phantoms of 4-20 cm thicknesses of polymethyl methacrylate slabs. Image quality was evaluated using DICOM images of a test object Leeds TOR 18-FG, through the numerical parameters signal-to-noise ratio (SNR), high-contrast spatial resolution (HCSR) and figure of merit (FOM). When PMMA thickness is increased and during a move from low fluoroscopy to cine modes, ESAK, SNR, HCSR and FOM values range from 0.44 to 391.0 μGy fr-1; 2.8 to 14.89; 3.17 to 15.54 and 0.51 to 79.94, respectively. The highest scattered dose rates recorded during the simulations were 1.79 and 8.04 mSv h-1 for the high fluoroscopy and cine modes, respectively.

Transcatheter Retrieval of Cardiovascular Foreign Bodies in Children: A 15-Year Single Centre Experience

There has been a rapid increase in the practice of interventional catheter treatment of congenital heart disease. Catheter retrieval of embolized cardiac devices and other foreign bodies is essential, yet no large studies have been reported in the paediatric population. Retrospective 15-year review of all children who underwent transcatheter foreign body retrieval in a tertiary cardiac centre from January 1997 to September 2012. Transcatheter retrieval of foreign bodies from the cardiovascular system was attempted in 78 patients [median age 4 (0.02-16) years and median weight 15 (1.7-74) kg] including 46 embolized devices. Transcatheter retrieval was successful in 70/78 (90%), surgical retrieval was required in 6. In two patients, small embolized coils were left in situ. Gooseneck snare was the most commonly used retrieval device. Median procedure and screening times were 90 (15-316) and 31 (2-161) min, respectively. There were no procedural deaths. Transient loss of foot pulses occurred in 5 and 2 patients required blood transfusion. Transcatheter retrieval of cardiovascular foreign bodies can be performed safely in the majority of children thus obviating the need for surgery. It is essential to have a comprehensive inventory of retrieval equipment and interventional staff conversant with its use.

Management of children with congenital heart defect: state of the art and future prospects

The treatment of children with congenital heart defects has evolved in the last 60 years from conservative care to a highly specialized management where advances in imaging, surgical, interventional and support techniques meet together to ensure satisfactory development and good quality of life to the child and to the upcoming grown up. Management of congenital heart defects best begins before birth with the aim, whenever possible, to maintain or establish biventricular physiology or, if this is excluded, to optimize the conditions for univentricular physiology. Current research in the field of genetics, device bioengineering and miniaturization, stem cell therapy, and fusion imaging technology is expected to help to improve further patient outcome. In this review, current management strategies and future prospects are discussed.

Radiation Exposure by Three-Dimensional Rotational Angiography (3DRA) During Trans-catheter Melody Pulmonary Valve Procedures (TMPV) in a Pediatric Cardiac Catheterization Laboratory

This retrospective study aims to evaluate radiation exposure by three-dimensional rotational angiography (3DRA) during trans-catheter Melody pulmonary valve (TMPV) procedures. 3DRA has been reported to have added value in the management of complex congenital heart disease aiding in the performance of interventional procedures albeit with concerns of higher radiation exposure. We test the hypothesis that 3DRA does not cause additional radiation exposure during TMPV procedures. We analyzed all 81 TMPV procedures performed at St. Louis Children's Hospital, MO, USA, from January 1, 2011 to December 31, 2014. Dose-area product (DAP), DAP indexed to body weight (DAP/BW), fluoroscopy time (FT), and weight-fluoroscopy time product of each procedure were recorded. We reviewed each procedure's images to determine whether additional interventions were performed (e.g., pulmonary artery angioplasty or treatment of conduit pseudo-aneurysm). 3DRA was used in 36 % of the procedures. 3DRA group had a higher number of additional procedures performed. The 3DRA group did not differ from the non-3DRA group in DAP, DAP/BW, and weight-fluoroscopy time product. 3DRA does not cause greater radiation exposure during TMPV procedures.

Patient doses in paediatric interventional cardiology: impact of 3D rotational angiography

The aim of this study was to calculate the contribution of 3D rotational angiography to radiation doses received by paediatric patients in a cardiac catheterisation laboratory. The percentage increase in the median value of air kerma-area product due to cone beam CT was 33 and 16% for diagnostic and therapeutic procedures, respectively. Results are presented separately for five age groups and ten weight groups. Several methods for reducing radiation from 3D rotational angiography are suggested and patient doses are compared with previously published values.

The First Ten of Everything: A Review of Past and Current Practice in Pediatric Cardiac Percutaneous Interventions

OBJECTIVES

This study was designed to compare outcomes of the most common pediatric cardiac interventions from the time of implementation with the current era.

BACKGROUND

Since the introduction of semilunar valve balloon dilation and device closure of the arterial duct and septal defects, development of interventional techniques and devices has been rapid. However, few studies have compared outcomes between those initial interventions and those in the current era.

METHODS

Five validated common catheter-based therapies were chosen for analysis, including atrial and duct device closure, balloon dilation of the aortic and pulmonary valves, and native coarctation of the aorta. A retrospective review of the first and most recent 10 consecutive patients in each group was performed.

RESULTS

There was a high mortality (30%) among neonates who underwent aortic valve (AV) dilation in the early era, but no mortality noted in other groups. In the early era, transcatheter atrial defect closure and AV dilations were associated with a low success rate (60% for both lesions) and a high complication rate (40% for atrial septal defect, 30% for AV dilations). Among the last 10 children, the atrial defect occlusion was successful in 100% without complications and AV dilations where successful in all children with a 30% complication rate (one major, two minor).

CONCLUSIONS

A learning curve with device development plays a significant role in the evolution of transcatheter techniques. These data provide baseline estimates of success and may be used as a template in the future when new techniques are adapted into practice.

A rare case of biventricular outflow obstruction with intact ventricular septum

We report a case of pulmonary atresia with intact ventricular septum and aortic valve stenosis in a neonate. This combination is extremely rare. Cardiac catheterization was performed at 2 days of age, which confirmed the prenatal echocardiographic diagnosis and identified associated moderate aortic valve stenosis. Soon after the examination, an urgent surgical intervention was required due to uncontrollable circulatory instability. The baby underwent a successful Fontan-type repair achieved by surgical management only.

Robotics and imaging in congenital heart surgery

The initial success seen in adult cardiac surgery with the application of available robotic systems has not been realized as broadly in pediatric cardiac surgery. The main obstacles include extended set-up time and complexity of the procedures, as well as the large size of the instruments with respect to the size of the child. Moreover, while the main advantage of robotic systems is the ability to minimize incision size, for intracardiac repairs, cardiopulmonary bypass is still required. Catheter-based interventions, on the other hand, have expanded rapidly in both application as well as the complexity of procedures and lesions being treated. However, despite the development of sophisticated devices, robotic systems to aid catheter procedures have not been commonly applied in children. In this article, we describe new catheter-like robotic delivery platforms, which facilitate safe navigation and enable complex repairs, such as tissue approximation and fixation, and tissue removal, inside the beating heart. Additional features including the tracking of rapidly moving tissue targets and novel imaging approaches are described, along with a discussion of future prospects for steerable robotic systems.

[Modern therapy of congenital heart defects]

Modern therapy of congenital heart defects consists of interventional and surgical procedures. The following report provides information about the most common congenital heart defects and the corresponding therapeutic options. Furthermore, the combined application of interventional and surgical procedures, so-called hybrid procedures, is described in detail as well as the latest developments in percutaneous valve replacement therapy.

Multiple transcatheter interventions in the same session in congenital cardiopathies

BACKGROUND

To investigate the methods of percutaneous transcatheter interventions for combined congenital heart disease and to evaluate its efficacy in children.

MATERIALS AND METHODS

Thirty cases (ages 3 days-13.5 years, body weight 3-35 kg) that underwent two multiple transcatheter interventions for combined or solitary congenital heart disease were retrospectively analyzed and presented.

RESULTS

A total of 61 transcatheter interventions were performed in 30 patients as combined procedures. In 29 patients, two different procedures were combined in the same session, in remaining one patient, combination of three interventions were performed in the same catheter session. Interventions performed in combined procedures were as follows: Coarctation balloon angioplasty in 12 cases, pulmonary balloon valvuloplasty in 10, PDA coil embolization in 10, aortic balloon valvuloplasty in 8, VSD closure in 5, ASD closure in 4, ductal stent implantation in 4, palliative pulmonary balloon valvuloplasty in 3, recanalization and angioplasty of the systemic-pulmonary shunt in 2, balloon atrial septostomy in one, aortic coarctation stent implantation in one, coil embolization of a pulmonary lobar sequestration in one and pulmonary valve perforation plus pulmonary balloon valvuloplasty in one were performed as first or second procedure. There was no mortality or major morbidity in relation to combined procedures.

CONCLUSION

Multiple transcatheter interventions in the same session are feasible, safe and effective with satisfactory good results. Second intervention may be performed as complementary procedure or independently to the first intervention.

The IMPACT registry: IMproving Pediatric and Adult Congenital Treatments

Tremendous advances have occurred in catheter-based interventions for congenital heart disease. Multicenter trials of these advances are either out of date or have been limited in scope. As such little is known on the application of these techniques in the current era. The IMPACT Registry (IMproving Pediatric and Adult Congenital Treatments) will allow us to measure variability in the performance and outcomes of both diagnostic and interventional cardiac catheterization procedures in all children and adults with congenital heart disease. The IMPACT Registry will be harmonized with the Society of Thoracic Surgeons Congenital Heart Disease Database, thereby allowing us to compare catheter-based interventions with surgical interventions when appropriate. The initial release of the registry will only include hospital-based outcomes, but ultimately it will transition to a longitudinal registry. The IMPACT Registry will provide the necessary benchmark tools for quality improvement activities for cardiac catheterization procedures in congenital heart disease.