Augmented Reality Visualization of 3D Rotational Angiography in Congenital Heart Disease: A Comparative Study to Standard Computer Visualization

Augmented reality (AR) visualization of 3D rotational angiography (3DRA) provides 3D representations of cardiac structures with full visualization of the procedural environment. The purpose of this study was to evaluate the feasibility of converting 3DRAs of congenital heart disease patients to AR models, highlight the workflow for 3DRA optimization for AR visualization, and assess physicians' perceptions of their use. This single-center study prospectively evaluated 30 retrospectively-acquired 3DRAs that were converted to AR, compared to Computer Models (CM). Median patient age 6.5 years (0.24-38.8) and weight 20.6 kg (3.4-107.0). AR and CM quality were graded highly. RV pacing was associated with higher quality of both model types (p = 0.02). Visualization and identification of structures were graded as "very easy" in 81.1% (n = 73) and 67.8% (n = 61) of AR and CM, respectively. Fifty-nine (66%) grades 'Agreed' or 'Strongly Agreed' that AR models provided superior appreciation of 3D relationships; AR was found to be least beneficial in visualization of aortic arch obstruction. AR models were thought to be helpful in identifying pathology and assisting in interventional planning in 85 assessments (94.4%). There was significant potential seen in the opportunity for patient/family counseling and trainee/staff education with AR models. It is feasible to convert 3D models of 3DRAs into AR models, which are of similar image quality as compared to CM. AR models provided additional benefits to visualization of 3D relationships in most anatomies. Future directions include integration of interventional simulation, peri-procedural counseling of patients and families, and education of trainees and staff with AR models.

Optimizing 3D Rotational Angiography for Congenital Cardiac Catheterization

The aim of the study was to determine the variables associated with high-quality (HQ) versus low-quality (LQ) three-dimensional rotational angiography (3DRA) and create guides for optimization of approach to 3DRA in congenital cardiac catheterization (CCC). CCC has adopted 3DRA as a mainstay, but there has not been systematic analysis of approach to and factors associated with HQ 3DRA. This was a single-center, retrospective study of 3DRAs using Canon Infinix-I platform. Reconstructions were graded by 3 interventionalists. Quality was dichotomized into HQ and LQ. Univariable analyses and multivariable logistic regression models were performed. From 8/2016 to 12/2018, 208 3DRAs were performed in 195 CCCs; median age 7 years (2, 16), weight 23 kg (12, 57). The majority of 3DRAs were performed in patients with biventricular physiology (N = 137, 66%) and in pulsatile sites (N = 144, 69%). HQ 3DRA (N = 182, 88%) was associated with greater total injection volume [2.20 mL/kg (1.44, 3.29) vs. 1.62 mL/kg (1.10, 1.98), p = 0.005] and more dilute contrast solution [60% (50, 100) vs. 100% (60, 100), p = 0.007], but not with contrast volume administered (p = 0.2) on univariable analysis. On multivariable logistic regression, HQ 3DRA was significantly associated with patient weight [OR 0.97 (95% CI (0.94, 0.99), p = 0.018], total injection volume [OR 1.04 (95% CI 1.01, 1.07) p = 0.011], and percent contrast solution [OR 0.97 (95% CI 0.95, 1.00), p = 0.022]. These data resulted in creation of scatter plots and a novel 3DRA Nomogram for estimating the probability of HQ 3DRA. This is the first study to create evidence-based contrast dose guides and nomogram for 3DRA in CCC. HQ 3DRA was associated with lower weight, higher total injection volumes, and more dilute contrast solution.

Troubled Judging of Bronchus Compression Due to Contrast-Filled Balloon in Three-Dimensional Rotational Angiography

Three-dimensional rotational angiography (3DRA) is a suitable technique to detect the risk of left main bronchus (LMB) compression during left pulmonary artery (LPA) stenting in partial cavopulmonary connection and total cavopulmonary connection (TCPC). We report on a case of a 4-year-old boy with hypoplastic left heart syndrome and TCPC in which 3DRA and bronchoscopy gave conflicting information on airway patency during balloon interrogation. The balloon with high contrast concentration created a severe artifact impeding visibility of the LMB. Simultaneous flexible bronchoscopy revealed an unobstructed LMB. Repeated 3DRAs with lower contrast concentration had no artifact and showed a patent airway in accordance with the bronchoscopy. Conventional LPA stenting was performed without indication for stent ovalization. The benefit of low contrast concentration in the interrogation balloon was demonstrated in a second case of an 11-year-old boy with TCPC. The margins of the LPA and LMB were clearly visible without blank-out artifact. Oval stent procedure was necessary to prevent LMB compression. When 3DRA is used for vessel-airway interrogation, the balloon contrast concentration should be low in order to avoid artifacts. When in doubt, simultaneous flexible bronchoscopy can overcome the dilemma in airway judgment.

Renaissance of Cardiac Imaging to Assist Percutaneous Interventions in Congenital Heart Diseases:The Role of Three-Dimensional Echocardiography and Multimodality Imaging

Percutaneous interventions have completely refashioned the management of children with congenital heart diseases (CHD) and the use of non-invasive imaging has become the gold standard to plan and guide these procedures in the modern era. We are now facing a dual challenge to improve the standard of care in low-risk patients, and to shift our strategies from the classic open chest surgery to imaging-guided percutaneous interventions in high-risk patients. Such rapid evolution of ultrasound technologies over the last 20 years have permitted the integration of transthoracic, transesophageal and intracardiac echocardiography into the interventional workflow to improve image guidance and reduce radiation burden from fluoroscopy and angiography. Specifically, miniaturization of transesophageal probe and advances in three-dimensional (3D) imaging techniques have enabled real-time 3D image guidance during complex interventional procedure, In addition, multimodality and fusion imaging techniques harness the strengths of different modalities to enhance understanding of anatomical and spatial relationship between different structures, improving communication and coordination between interventionalists and imaging specialists. In this review, we aim to provide an overview of 3D imaging modalities and multimodal fusion in procedural planning and live guidance of percutaneous interventions. At the present times, 3D imaging can no longer be considered a luxury but a routine clinical tool to improve procedural success and patient outcomes.

Use of rotational angiography in congenital cardiac catheterisations to generate three-dimensional-printed models

BACKGROUND

Three-dimensional printing is increasingly utilised for congenital heart defect procedural planning. CT or MR datasets are typically used for printing, but similar datasets can be obtained from three-dimensional rotational angiography. We sought to assess the feasibility and accuracy of printing three-dimensional models of CHD from rotational angiography datasets.

METHODS

Retrospective review of CHD catheterisations using rotational angiography was performed, and patient and procedural details were collected. Imaging data from rotational angiography were segmented, cleaned, and printed with polylactic acid on a Dremel® 3D Idea Builder (Dremel, Mount Prospect, IL, USA). Printing time and materials' costs were captured. CT scans of printed models were compared objectively to the original virtual models. Two independent, non-interventional paediatric cardiologists provided subjective ratings of the quality and accuracy of the printed models.

RESULTS

Rotational angiography data from 15 catheterisations on vascular structures were printed. Median print time was 3.83 hours, and material costs were $2.84. The CT scans of the printed models highly matched with the original digital models (root mean square for Hausdorff distance 0.013 ± 0.003 mesh units). Independent reviewers correctly described 80 and 87% of the models (p = 0.334) and reported high quality and accuracy (5 versus 5, p = NS; κ = 0.615).

CONCLUSION

Imaging data from rotational angiography can be converted into accurate three-dimensional-printed models of CHD. The cost of printing the models was negligible, but the print time was prohibitive for real-time use. As the speed of three-dimensional printing technology increases, novel future applications may allow for printing patient-specific devices based on rotational angiography datasets.

A novel diagnostic approach for assessing pulmonary blood flow distribution using conventional X-ray angiography

Objective

Quantitative assessment of pulmonary blood flow distribution is important when determining the clinical indications for treating pulmonary arterial branch stenosis. Lung perfusion scintigraphy is currently the gold standard for quantitative blood flow measurement. However, it is expensive, cannot provide a real-time assessment, requires additional sedation, and exposes the patient to ionizing radiation. The aim of this study was to investigate the feasibility of a novel technology for measuring pulmonary blood flow distribution in each lung by conventional X-ray pulmonary angiography and to compare its performance to that of lung perfusion scintigraphy.

Methods

Contrast-enhanced X-ray pulmonary angiography images were acquired at a frame rate of 30 frames per second. The baseline mask image, obtained before contrast agent injection, was subtracted from subsequent, consecutive images. The time-signal intensity curves of two regions of interest, established at each lung field, were obtained on a frame-to-frame basis. The net increase in signal intensity within each region at the torrent period during the second cardiac cycle before contrast agent enhancement over the total lung field was measured, and the right-to-left ratio of the signal intensity was calculated. The right-to-left ratio obtained with this approach was compared to that obtained with scintigraphy. Agreement of the right-to-left ratio between X-ray angiography and lung scintigraphy measurements was assessed using linear fitting with the Pearson correlation coefficient.

Result

The calculation of the right-to-left ratio of pulmonary blood flow by our kinetic model was feasible for seven children as a pilot study. The right-to-left ratio of pulmonary blood flow distribution calculated from pulmonary angiography was in good agreement with that of lung perfusion scintigraphy, with a Pearson correlation coefficient of 0.91 and a slope of linear fit of 1.2 (p<0.005).

Conclusion

The novel diagnostic technology using X-ray pulmonary angiography from our kinetic model can feasibly quantify the right-to-left ratio of pulmonary blood flow distribution. This technology may serve as a substitute for lung perfusion scintigraphy, which is quite beneficial for small children susceptible to radiation exposure.

Radiation dose reduction for 3D angiography images in pediatric and congenital cardiology

OBJECTIVES

The purpose of this study was to investigate the influence of simulated reduced-dose three-dimensional angiography (3DA) on the accuracy and precision of linear measurements derived from 3DA datasets.

BACKGROUND

Three-dimensional angiography is performed during X-ray guided interventional procedures to aid diagnosis and inform treatment strategies for children and adults with congenital heart disease. However, 3DA contributes substantially to patient radiation dose and may lead to an increased radiation-induced cancer risk.

METHODS

Reduced-dose patient 3DA images were simulated by adding quantum noise to the 2D projection angiograms, then reconstructing the projection angiograms into the 3DA dataset. Dose reduction in the range 33-72% was simulated. Five observers performed 46 vessel diameter measurements along prespecified axes within 23 vessel segments from 11 patient 3DA datasets. Statistical tests were performed to assess the influence of radiation dose reduction on the accuracy and precision of vessel diameter measurements.

RESULTS

Vessel diameter measurements were in the range 5.9- 22.7 mm. Considering all vessel segments and observers, the influence of dose level on the accuracy of diameter measurements was in the range 0.02 - 0.15 mm (p .05-.8). Interobserver variability increased modestly with vessel diameter, but was not influence by dose level (p = .52). The statistical test for observer recall bias was negative (p = .51).

CONCLUSIONS

Simulated dose reduction up to 72% did not affect the accuracy or precision of the diameter measurements acquired from 3DA images. These findings may embolden 3DA radiation dose reduction for pediatric and congenital heart disease patients.

Three-Dimensional Rotational Angiography during Catheterization of Congenital Heart Disease - A ten Years' experience at a single center

This paper aims to assess the usability and advantages of three-dimensional rotational angiography (3DRA) in patients with congenital heart disease (CHD) and its application in the cath lab. Up to now, its use in CHD is not widespread or standardized. We analyzed all patients with CHD who underwent a 3DRA at our facility between January 2010 and May 2019. The 3DRAs were evaluated for radiation exposure, contrast dye consumption, diagnostic utility and image quality. We performed 872 3DRAs. 3DRA was used in 67.1% of the cases for interventional procedures and in 32.9% for diagnostic purposes. Two different acquisition programs were applied. The median dose-area product (DAP) for all 872 rotations was 54.1 µGym² (21.7–147.5 µGym²) and 1.6 ml/kg (0.9–2.07 ml/kg) of contrast dye was used. Diagnostic utility of the generated 3D-model was rated superior to the native 3D angiography in 94% (819/872). 3DRA is an excellent and save diagnostic and interventional tool. However, 3DRA has not become a standard imaging procedure in pediatric cardiology up to now. Effort and advantage seems to be unbalanced, but new less invasive techniques may upgrade this method in future.

Treatment of Peripheral Pulmonary Artery Stenosis

Peripheral pulmonary artery stenosis (PAS) is an abnormal narrowing of the pulmonary vasculature and can form anywhere within the pulmonary artery tree. PAS is a congenital or an acquired disease, and its severity depends on the etiology, location, and number of stenoses. Most often seen in infants and young children, some symptoms include shortness of breath, fatigue, and tachycardia. Symptoms can progressively worsen over time as right ventricular pressure increases, leading to further complications including pulmonary artery hypertension and systolic and diastolic dysfunctions. The current treatment options for PAS include simple balloon angioplasty, cutting balloon angioplasty, and stent placement. Simple balloon angioplasty is the most basic therapeutic option for proximally located PAS. Cutting balloon angioplasty is utilized for more dilation-resistant PAS vessels and for more distally located PAS. Stent placement is the most effective option seen to treat the majority of PAS; however, it requires multiple re-interventions for serial dilations and is generally reserved for PAS vessels that are resistant to angioplasty.

Oval stenting in left pulmonary artery stenosis: a novel double balloon technique to prevent airway compression in single ventricle

AIMS

Left pulmonary artery (LPA) stenosis is common in patients with cavopulmonary connections. Stent implantation is the treatment of choice but may be complicated or contraindicated by left main bronchus (LMB) compression due to limited retro-aortic space after a Damus-Kaye-Stansel (DKS) or Norwood operation. This study describes a novel double balloon technique of LPA stenting in patients at risk of LMB compression.

METHODS AND RESULTS

A cohort study was performed in 11 patients who underwent LPA stenting with an oval stent technique between 2015 and 2018. Retro-aortic anatomy was evaluated periprocedurally by three-dimensional rotational angiography (3DRA). Pre-existing LMB compression was demonstrated by 3DRA in seven out of eight patients who had undergone previous LPA stenting and in one patient without stenting. Primary ovalisation with immediate stent implantation on double balloons was performed in one patient. Ten patients had secondary ovalisation with single balloon stent implantation followed by the double balloon technique for ovalisation. The procedures were successful in all patients and guaranteed LMB patency without increasing pre-existing compression.

CONCLUSIONS

The 3DRA-guided oval stent technique with double balloon inflation is successful in treating LPA stenosis after a DKS or Norwood operation in patients at risk of bronchial compression, guaranteeing LMB patency without increasing pre-existing compression.

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.

Pros, cons and future perspectives - three questions on three dimensional guidance for cardiac catheterization in congenital heart disease

Step changes in angiographic imaging are not commonplace. Since the move from analogue to digital and flat detector plates, two-dimensional imaging technology has certainly evolved but not jumped forward. Of all the routine imaging techniques used in cardiology, angiography has been the last modality to embrace the third dimension. Although the development of rotational angiography was initially for the benefit of neuroimaging and fusion of cross sectional datasets was aimed at the treatment of descending aortic pathology, interventional physicians in congenital and structural cardiology have immersed themselves in this technology over the last 10 years. Like many disruptive technologies, its introduction has divided opinion. We aimed to explore the mindset of those in the field of interventional cardiology who are driving imaging forward. These structured interviews recorded during the 21^st Pediatric and Adult Interventional Cardiac Symposium illustrate the challenges and sticking points as well as giving an insight into the direction of travel for three-dimensional imaging and fusion techniques. Covering a wide range of career development, seniority and experience, the interviewees in this article are probably responsible for the majority of the published literature on invasive three-dimensional imaging in congenital heart disease.

Three-dimensional rotational angiography in congenital heart disease: Present status and evolving future

Three-dimensional rotational angiography (3D-RA) enables volumetric imaging through rotation of the C-arm of an angiographic system and real-time 3D reconstruction during cardiac catheterization procedures. In the field of congenital heart disease (CHD), 3D-RA has gained considerable traction, owing to its capability for enhanced visualization of spatial relationships in complex cardiac morphologies and real time image guidance in an intricate interventional environment. This review provides an overview of the current applications, strengths, and limitations of 3D-RA acquisition in the management of CHD and potential future directions. In addition, issues of dosimetry, radiation exposure, and optimization strategies will be reviewed. Further implementation of 3D-RA will be driven by patient benefits relative to existing 3D imaging capabilities and fusion techniques balanced against radiation exposure.

X-ray fused with MRI guidance of pre-selected transcatheter congenital heart disease interventions

OBJECTIVES

To determine whether X-ray fused with MRI (XFM) is beneficial for select transcatheter congenital heart disease interventions.

BACKGROUND

Complex transcatheter interventions often require three-dimensional (3D) soft tissue imaging guidance. Fusion imaging with live X-ray fluoroscopy can potentially improve and simplify procedures.

METHODS

Patients referred for select congenital heart disease interventions were prospectively enrolled. Cardiac MRI data was overlaid on live fluoroscopy for procedural guidance. Likert scale operator assessments of value were recorded. Fluoroscopy time, radiation exposure, contrast dose, and procedure time were compared to matched cases from our institutional experience.

RESULTS

Forty-six patients were enrolled. Pre-catheterization, same day cardiac MRI findings indicated intervention should be deferred in nine patients. XFM-guided cardiac catheterization was performed in 37 (median age 8.7 years [0.5-63 years]; median weight 28 kg [5.6-110 kg]) with the following prespecified indications: pulmonary artery (PA) stenosis (n = 13), aortic coarctation (n = 12), conduit stenosis/insufficiency (n = 9), and ventricular septal defect (n = 3). Diagnostic catheterization showed intervention was not indicated in 12 additional cases. XFM-guided intervention was performed in the remaining 25. Fluoroscopy time was shorter for XFM-guided intervention cases compared to matched controls. There was no significant difference in radiation dose area product, contrast volume, or procedure time. Operator Likert scores indicated XFM provided useful soft tissue guidance in all cases and was never misleading.

CONCLUSIONS

XFM provides operators with meaningful three-dimensional soft tissue data and reduces fluoroscopy time in select congenital heart disease interventions.

Three-Dimensional Rotational Angiography in Pediatric Patients with Congenital Heart Disease: A Literature Review

Cardiac catheterization is a commonly used form of imaging and treatment in pediatric patients with congenital heart disease. Traditionally, two-dimensional conventional angiography was the method used, but since 2000 three-dimensional rotational angiography (3DRA) is increasingly used in the field of cardiology in both adult and pediatric patients. To investigate the use and applications of 3DRA in pediatric congenital cardiology, literature was systematically reviewed and 29 eligible articles were found. Those showed that 3DRA is already a greatly valued diagnostic and therapeutic technique in pediatric cardiology. However, the literature misses well-designed clinical, homogeneous, multicenter, prospective studies recording data in a standardized manner. These studies are necessary to ensure proper data analysis and to investigate the true advantages of 3DRA and how it exactly benefits the patients.

Innovative interventional catheterization techniques for congenital heart disease

Since 1929, when the first cardiac catheterization was safely performed in a human by Dr. Werner Forssmann (on himself), there has been a rapid progression of cardiac catheterization techniques and technologies. Today, these advances allow us to treat a wide variety of patients with congenital heart disease using minimally invasive techniques; from fetus to infants to adults, and from simple to complex congenital cardiac lesions. In this article, we will explore some of the exciting advances in cardiac catheterization for the treatment of congenital heart disease, including transcatheter valve implantation, hybrid procedures, biodegradable technologies, and magnetic resonance imaging (MRI)-guided catheterization. Additionally, we will discuss innovations in imaging in the catheterization laboratory, including 3D rotational angiography (3DRA), fusion imaging, and 3D printing, which help to make innovative interventional approaches possible.

Recent advances in cardiac catheterization for congenital heart disease

The field of pediatric and adult congenital cardiac catheterization has evolved rapidly in recent years. This review will focus on some of the newer endovascular technological and management strategies now being applied in the pediatric interventional laboratory. Emerging imaging techniques such as three-dimensional (3D) rotational angiography, multi-modal image fusion, 3D printing, and holographic imaging have the potential to enhance our understanding of complex congenital heart lesions for diagnostic or interventional purposes. While fluoroscopy and standard angiography remain procedural cornerstones, improved equipment design has allowed for effective radiation exposure reduction strategies. Innovations in device design and implantation techniques have enabled the application of percutaneous therapies in a wider range of patients, especially those with prohibitive surgical risk. For example, there is growing experience in transcatheter duct occlusion in symptomatic low-weight or premature infants and stent implantation into the right ventricular outflow tract or arterial duct in cyanotic neonates with duct-dependent pulmonary circulations. The application of percutaneous pulmonary valve implantation has been extended to a broader patient population with dysfunctional ‘native’ right ventricular outflow tracts and has spurred the development of novel techniques and devices to solve associated anatomic challenges. Finally, hybrid strategies, combining cardiosurgical and interventional approaches, have enhanced our capabilities to provide care for those with the most complex of lesions while optimizing efficacy and safety.

Transcoronary cell infusion with the stop-flow technique in children with single-ventricle physiology

BACKGROUND

Almost all reports on cardiac regeneration therapy have referred to adults, and only a few have focused on transcoronary infusion of cardiac progenitor cells using the stop-flow technique in children.

METHODS

Intracoronary autologous cardiosphere-derived cell (CDC) transfer was conducted at Okayama University as a phase 1 clinical trial for seven patients with hypoplastic left heart syndrome between January 2011 and December 2012, and as a phase 2 clinical trial for 34 patients with single-ventricle physiology between July 2013 and March 2015.

RESULTS

A total of 41 patients with single-ventricle physiology underwent transcoronary infusion of CDC with the stop-flow technique. The median age was 33 months (range, 5-70 months) and the median weight was 10.1 kg (range, 4.1-16.0 kg). Transient adverse events occurred during the procedure, including ST-segment elevation or depression, hypotension, bradycardia, and coronary artery vasospasm. All patients completely recovered. There were no major procedure-related adverse events. In this study, transcoronary infusion of CDC using the stop-flow technique was successfully completed in all patients.

CONCLUSION

Transcoronary infusion of CDC using the stop-flow technique in children is a feasible and safe procedure.

Use of 3-D digital subtraction rotational angiography during cardiac catheterization of infants and adults with congenital heart diseases

OBJECTIVE

To compare image quality, radiation and contrast doses required to obtain 3D-Digital subtraction rotational angiography (3D-DSRA) with 3D-Digital rotational angiography (3D-DRA) in infants (children ≤ 2 years of age) and adults with congenital heart diseases (ACHD).

BACKGROUND

3D-DRA can be performed with radiation doses comparable to bi-plane cine-angiography. However, 3D-DRA in infants requires a large contrast volume. The resolution of 3D-DRA performed in ACHD patients is limited by their soft tissue density. We hypothesized that the use of 3D-DSRA could help alleviate these concerns.

METHODS

Radiation (DAP) and contrast doses required to obtain 3D-DSRA was compared with 3D-DRA in 15 age-, size-, and intervention-matched infants and 15 ACHD patients. The diagnostic quality and utility of these two modalities were scored by 4 qualified independent observers.

RESULTS

Both in infants and adults, the median contrast volume for 3D-DSRA was lower than 3D-DRA (0.98 vs. 1.81 mL/kg; P < 0.001 and 0.92 vs. 1.4 mL/kg; P < 0.001, respectively) with an increased DAP (median: 188 vs. 128 cGy cm² ; P = 0.068 and 659 vs. 427 cGy cm² ; P = 0.045, respectively). The diagnostic quality and utility scores for rotational-angiography, and 3D-reconstruction were superior for 3D-DSRA (score = 94 vs. 80%, P = 0.03 and 90 vs.79%, P = 0.01, respectively) and equivalent for multi-planar-reformation and 3D-roadmapping in ACHD patients compared with 3D-DRA. All scores for both modalities were equivalent for infants.

CONCLUSIONS

3D-DSRA can be acquired using lower contrast volume with a mildly higher radiation dose than 3D-DRA in infants and ACHD patients. The diagnostic quality and utility scores for 3D-DSRA were higher in ACHD patients and equivalent for infants compared with 3D-DRA.

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.

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.

Diagnostic Utility of Three-Dimensional Rotational Angiography in Congenital Cardiac Catheterization

We evaluated the diagnostic utility of the three modalities of three-dimensional rotational angiography (3DRA): rotational angiography (RA), multiplanar reformat (MPR) and three-dimensional angiographic reconstruction (3D-R) in pediatric cardiac catheterization. The 3DRA studies were classified by anatomy of interest based on our injection protocol: pulmonary arteries (PA), aorta, cavopulmonary connection (CPC), and others. Retrospective review of 3DRA images by two reviewers for each modality was conducted with grading as inferior, similar, or superior in comparison with the diagnostic quality of fixed-plane angiography (FPA). The percentages of grades for each modality were averaged. Weighted kappa statistic was used to evaluate inter-rater reliability. In total, 114 3DRA studies were performed on 87 patients between August 2010 and March 2012. Median age was 2.7 years (1 day-48.4 years) and median weight 12.1 kg (3.6-106.5 kg). For RA: 79.4 % of the studies were of diagnostic quality and 52.2 % were superior; 3D-R: 82 % were of diagnostic quality and 65.8 % were superior; and MPR: 83.5 % were of diagnostic quality and 63 % were superior. Overall 3DRA technologies (RA, 3D-R, MPR) were of diagnostic quality or better in 111/114 (97.4 %) studies and 103/114 (90.4 %) were judged superior. Most common reasons for inferior grading were limited opacification and metallic artifact. In pediatric cardiac catheterization, 3DRA imaging was of diagnostic quality and frequently provided additional clinically relevant data when compared to FPA.

Three-dimensional rotational angiography in children with an aortic coarctation

Background

Children with aortic coarctations (CoA) are increasingly percutaneously treated. Good visualisation of the CoA is mandatory and can be obtained with three-dimensional rotational angiography (3DRA). This study aims to compare the diagnostic and therapeutic additional value of 3DRA with conventional biplane angiography (CA) in children with a CoA.

Methods

Patients undergoing percutaneous treatment of CoA with balloon angioplasty (BA) or stent between 2003 and 2015, were retrospectively reviewed on success rate, complications, radiation and technical settings. Diagnostic quality of CA and 3DRA and additional value of 3DRA were scored.

Results

In total, 134 patients underwent 183 catheterisations, 121 CA and 62 3DRA-guided. Median age was 0.52 years in the BA group and 11.19 years in the stent group. 3DRA was superior to CA in displaying the left ventricle (p = 0.008), ascending aorta (p < 0.001), aortic arch (p = 0.005) and coronary arteries (p < 0.001). In the BA group, 3DRA had a significantly higher success rate than CA (100.0 % versus 68.9 %, p = 0.016). All stent interventions were successful. Complication rates did not differ significantly. The median total dose area product did not significantly differ between CA and 3DRA in the BA (27.88 μGym²/kg versus 15.81 μGym²/kg, p = 0.275) or stent group (37.34 μGym²/kg versus 45.24 μGym²/kg, p = 0.090). 3DRA was of additional value in 96.8 % of the interventions.

Conclusions

3DRA is superior to CA in diagnostic quality and not associated with increased radiation exposure. It provides high additional value in guiding CoA related interventions.

Electronic supplementary material

The online version of this article (doi: 10.1007/s12471-016-0899-2) contains supplementary material, which is available to authorized users.

Three-Dimensional Rotational Angiography in the Pediatric Cath Lab: Optimizing Aortic Interventions

The aim of this study was to evaluate usability and accuracy of three-dimensional rotational angiography (3DRA) during interventions of the aorta in congenital heart disease (CHD). 3DRA is an accurate, encompassing and fast imaging technique in the cath lab. However, there is only few published data about its use during interventions in CHD. Between January 2010 and January 2014, 3DRA was performed in 77 patients with aortic issues: in 65 % cases, an intervention was performed, of which 72 % had aortic isthmus stenosis. Data were obtained retrospectively. The accuracy of 3DRA was evaluated on the basis of comparative measurements (n = 60) of the aortic diameter between 3DRA and conventional biplane angiography. Measurements presented a high accuracy with an average deviation of 3.89 % [±3 %] and a significant correlation of r = 0.99 after Pearson (p < 0.0001). Clinical benefit was assessed using a five-point Likert scale and could be shown in 98 %. Comparison with a control group showed a reduced fluoroscopy time from 10.2 to 8.30 min (median, p < 0.01) and decreased radiation dose of 0.18 compared to 0.56 Gy cm(2)/kg (median, p < 0.02). The use of 3DRA in patients with aortic anomalies has advantages in comparison with conventional angiography. It improves diagnostic accuracy, and 3D guidance enables a faster and simplified intervention with enhanced patients' safety and the potential to reduce radiation dose.

Multimodality 3-dimensional image integration for congenital cardiac catheterization

Cardiac catheterization procedures for patients with congenital and structural heart disease are becoming more complex. New imaging strategies involving integration of 3-dimensional images from rotational angiography, magnetic resonance imaging (MRI), computerized tomography (CT), and transesophageal echocardiography (TEE) are employed to facilitate these procedures. We discuss the current use of these new 3D imaging technologies and their advantages and challenges when used to guide complex diagnostic and interventional catheterization procedures in patients with congenital heart disease.

An Overview of Pulmonary Atresia and Major Aortopulmonary Collateral Arteries

Pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries (PA/VSD/MAPCAs) is a rare and complex congenital cardiac lesion that has historically carried a poor prognosis. With advancements in surgical management, we have seen an improvement in the outcomes for children affected by this disease. However, this population continues to present challenges due to the complex anatomy and physiology associated with PA/VSD/MAPCA. This summary of material presented during one of the nursing sessions of the 2014 Meeting of the Pediatric Cardiac Intensive Care Society provides an overview for those in cardiac intensive care units who do not have a large experience with this lesion. We will review the anatomy, physiology, surgical approach, postoperative management strategies, and cardiac catheter intervention options for PA/VSD/MAPCAs. We will also discuss recent innovations that may lead to continued improvement in outcomes for this challenging patient population.

Bronchial compression following pulmonary artery stenting in single ventricle lesions: how to prevent, and how to decompress

OBJECTIVES

To assess airway compression during pulmonary artery (PA) intervention in single ventricle (SV) palliation.

BACKGROUND

SV lesions with a prominent neo-aortic root are considered a high risk for branch PA and/or bronchial stenosis. PA stenting is well established, but may result in ipsilateral bronchial compression.

METHODS

Single-centre retrospective analysis of 19 palliated SV patients with branch PA stenosis and close proximity to the ipsilateral main bronchus who underwent cardiac catheterisation at a median age and weight of 8.5 years (0.5-25) and 16.5 kg (6-82) between 12/2011 and 05/2015.

RESULTS

Two of the 19 patients suffered an almost-closed left-main bronchus (LMB) following PA stenting. Fortunately, LMB decompression succeeded in both those patients by re-shaping the PA stents by compressing the chest while splinting the LMB with an inflated balloon. To prevent the other 17 patients from suffering this serious complication, we adopted a thorough preparation strategy: 13 patients underwent safe simultaneous bronchoscopy and cardiac catheterisation; in the remaining 4 patients CT-angiography enabled accurate risk evaluation prior to re-catheterisation.

CONCLUSIONS

In SV lesions accompanied by branch PA stenosis, thorough preparation via cross-sectional imaging is mandatory, including simultaneous bronchoscopy and cardiac catheterisation in selected cases, to rule out any airway compression before considering endovascular stent implantation. If a PA stent's compression has already caused severe bronchial obstruction, our balloon-splinted decompression technique should be considered.

Three-dimensional rotational angiography in the assessment of vascular and airway compression in children after a cavopulmonary anastomosis

The aim of the study was to examine the role of three-dimensional rotational angiography (3DRA) in assessing vascular and airway narrowing in children with a bidirectional cavopulmonary anastomosis (BCPA). The course of children with single ventricle physiology is often complicated by left pulmonary artery (LPA) and/or bronchial stenosis and may be related to aortic compression. 3DRA may be useful in evaluating this complex anatomy and possible mechanisms for the observed obstruction. Clinical data and imaging (2D angiography and 3DRA) of children with a BCPA were reviewed retrospectively. Measurements were taken at similar locations along the pulmonary arteries in both modalities and in the airways on 3DRA. Twenty-five children with a previous BCPA were assessed at mean age of 3.1 ± 2.0 years and weight of 13.6 ± 3.6 kg. Excellent correlation was found between 3DRA and 2D angiographic LPA measurements (r = 0.89, p < 0.0001). Twelve children had qualitative LPA stenosis on 3DRA, with a stenotic dimension of 6.6 ± 2.2 mm on 2D angiography and 6.8 ± 1.9 mm on 3DRA (r = 0.94, p < 0.0001). Ten cases with LPA stenosis also had bronchial stenosis (83 %). Qualitative airway assessment correlated with quantitative bronchial dimensions from 3DRA-derived tomographic images: Bronchial stenosis measured 4.4 ± 1.6 versus 5.9 ± 1.1 mm in those with a normal appearing bronchus (p = 0.009). Hybrid patients (initial palliation with bilateral pulmonary artery banding and arterial ductal stenting, n = 5) and all patients with a Damus-Kaye-Stansel (DKS) anastomosis (n = 9) were more likely to have LPA and left bronchial stenosis (OR 7.7, p = 0.04). 3DRA is a useful and accurate tool in assessment of LPA and airway narrowing after BCPA. Hybrid and DKS patients are more prone to LPA and bronchial stenosis, and 3DRA can provide insight into the mechanism.

A comparison of radiation dose between standard and 3D angiography in congenital heart disease

Background

The use of three-dimensional rotational angiography (3D-RA) to assess patients with congenital heart diseases appears to be a promising technique despite the scarce literature available.

Objectives

The objective of this study was to describe our initial experience with 3D-RA and to compare its radiation dose to that of standard two-dimensional angiography (2D-SA).

Methods

Between September 2011 and April 2012, 18 patients underwent simultaneous 3D-RA and 2D-SA during diagnostic cardiac catheterization. Radiation dose was assessed using the dose-area-product (DAP).

Results

The median patient age and weight were 12.5 years and 47.5 Kg, respectively. The median DAP of each 3D-RA acquisition was 1093µGy.m² and 190µGy.m² for each 2D-SA acquisition (p<0.01). In patients weighing more than 45Kg (n=7), this difference was attenuated but still significant (1525 µGy.m² vs.413µGy.m², p=0.01). No difference was found between one 3D-RA and three 2D-SA (1525µGy.m² vs.1238 µGy.m², p = 0.575) in this population. This difference was significantly higher in patients weighing less than 45Kg (n=9) (713µGy.m² vs.81µGy.m², P = 0.008), even when comparing one 3D-RA with three 2D-SA (242µGy.m², respectively, p<0.008). 3D-RA was extremely useful for the assessment of conduits of univentricular hearts, tortuous branches of the pulmonary artery, and aorta relative to 2D-SA acquisitions.

Conclusions

The radiation dose of 3D-RA used in our institution was higher than those previously reported in the literature and this difference was more evident in children. This type of assessment is of paramount importance when starting to perform 3D-RA.

Use of the pressure wire method for measuring pulmonary arterial pressures in patients with pulmonary atresia

OBJECTIVE

The objective of the study was to analyse the use of the pressure wire for the acquisition of intravascular pulmonary pressures in the presence of pulmonary atresia and systemic-dependent pulmonary blood flow.

METHODS

In this study, we included patients with pulmonary atresia and systemic-dependent pulmonary circulation referred for diagnostic catheterisation for evaluation of pulmonary pressures during the period from April, 2012 to April, 2013. The systemic-pulmonary collateral arteries were selectively catheterised, and in the absence of a critical stenosis angiographically determined; the pressure wire was introduced in these arteries to reach the main pulmonary artery, and/or lobar, and segmental branches. Aortic and pulmonary pressures were simultaneously obtained. We evaluated the feasibility and safety of the method.

RESULTS

We studied 10 patients (age 21 days to 11 years). In all of them, the pressures of pulmonary circulation - main artery, and/or lobar, and segmental branches - were successfully measured with the pressure wire. Of eight patients with indication for Rastelli surgery, the pulmonary pressures were considered normal in five, and slightly increased in three. In two patients requiring univentricular correction - total cavopulmonary anastomosis - the diastolic pressure was increased (20 mmHg). All procedures were performed without haemodynamic instability, cardiac arrhythmia, systemic saturation reduction, death, or any other complication.

CONCLUSION

Measurement of pulmonary vascular pressures using the pressure wire in small patients with pulmonary atresia is safe and effective. It allows the acquisition of reliable pressure curves, even in the presence of small vessels, bending and tortuosity, without the risk usually associated with the use of conventional diagnostic catheters.

Effective radiation dosage of three-dimensional rotational angiography in children

AIMS

Three-dimensional rotational angiography (3DRA) is a relatively new but promising imaging technique in the paediatric catheterization laboratory. However, data on effective dose (ED) of this technique in children are lacking. The purpose of this study is to provide ED of 3DRA and to correlate this with parameters readily available in daily practice. Furthermore, the effect of dose-reducing techniques is evaluated.

METHODS AND RESULTS

Effective doses were calculated with Monte Carlo PCXMC 2.0 in 14 patients who underwent a total of 17 3DRAs at our paediatric catheterization laboratory. Median age was 5.7 years (range 1 day-16.6 years). Median ED was 1.6 milliSievert (mSv) (range 0.7-4.9). Effective dose did not correlate with age and body surface area but did correlate with dose area product (DAP) and milliGray (mGy) with r(2) of 0.75 and 0.83, respectively. Reduction of the total amount of frames from 248 to 133 per rotation resulted in further dose reduction of over 50% with preserved image quality.

CONCLUSION

The median ED of 3DRA in children is 1.6 mSv and correlates with DAP and mGy. This dose can be halved by applying frame reduction. A significant further dose reduction can be achieved by obtaining additional knowledge of the equipment used.

Evolving trends in interventional cardiology: endovascular options for congenital disease in adults

As increasing numbers of patients with congenital heart disease enter adulthood, there is a growing need for minimally invasive percutaneous interventions, primarily to minimize the number of repeated surgeries required by these patients. The use of percutaneous devices is commonplace for the treatment of simple lesions, such as atrial septal defect, patent foramen ovale, patent duct arteriosus, and abnormal vascular connections. There is also substantial experience with device closure of membranous and muscular ventricular septal defects, as well as more complex shunts such as baffle leaks after atrial switch repair and ventricular pseudoaneurysms. An increasing use of covered stents has improved the safety of aortic coarctation, conduit, and branch pulmonary stenosis interventions. Percutaneous pulmonary valve implantation now has an established role in the setting of dysfunctional right ventricle-pulmonary artery conduits or failing bioprosthetic pulmonary valves. Many patients remain unsuitable for percutaneous pulmonary valve implantation because of large diameter "native" outflow tracts, however, various techniques have emerged and multiple devices are in development to provide solutions for these unique anatomic challenges. Hybrid approaches involving use of surgical and transcatheter techniques are increasingly common, serving to optimize efficacy and safety of certain procedures; they depend on a collaborative and collegial relationship between cardiac surgeons and interventionalists that is primarily patient-centred.

Catheter Interventions for Pulmonary Artery Stenosis: Matching the Intervention with the Pathology

Pulmonary artery (PA) stenosis represents a heterogeneous defect with a wide morphology and etiology. Interventions to treat PA stenosis should be based on the location, severity, and cause of stenosis as well as the size of the patient at presentation. Specialized dilation balloons, stents, and delivery techniques have been developed to treat a variety of PA stenoses in small infants through adulthood. Early and intermediate results of angioplasty and stenting are superior to surgical results, while long-term data on angioplasty and stenting are becoming available for these proven safe and effective techniques.

Multimodality Imaging in Congenital Heart Disease: an Update

The increasing number of survivors of congenital heart disease (CHD) has been paralleled by advancement of imaging modalities used for the ongoing assessment of these patients. There has been a large body of literature describing new approaches to non-invasive assessment of CHD. We will review new applications of well established as well as novel techniques for the management and understanding of CHD.