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

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.

Magnetic resonance and computed tomography imaging fusion for live guidance of percutaneous pulmonary valve implantation

Introduction

Until recently, two-dimensional (2D) angiography was the mainstay of guidance for percutaneous pulmonary valve implantation (PPVI). Recent advances in fusion software have enabled direct fusion of pre-intervention imaging, magnetic resonance imaging (MRI) or computed tomography (CT) scans, to create a reliable three-dimensional (3D) roadmap for procedural guidance.

Aim

To report initial two-center experience with direct 2D–3D image fusion for live guidance of PPVI with MRI- and CT-derived 3D roadmaps.

Material and methods

We performed a prospective study on PPVIs guided with the new fusion imaging platform introduced in the last quarter of 2015.

Results

3D guidance with an MRI- (n = 14) or CT- (n = 8) derived roadmap was utilized during 22 catheterizations for right ventricular outflow tract balloon sizing (n = 7) or PPVI (n = 15). Successful 2D–3D registration was performed in all but 1 patient. Six (27%) patients required intra-procedural readjustment of the 3D roadmap due to distortion of the anatomy after introduction of a stiff wire. Twenty-one (95%) interventions were successful in the application of 3D imaging. Patients in the CT group received less contrast volume and had a shorter procedural time, though the differences were not statistically significant. Those in the MRI group had significantly lower weight adjusted radiation exposure.

Conclusions

With intuitive segmentation and direct 2D–3D fusion of MRI or CT datasets, VesselNavigator facilitates PPVI. Our initial data show that utilization of CT-derived roadmaps may lead to less contrast exposure and shorter procedural time, whereas application of MRI datasets may lead to lower radiation exposure.

Great Vessels Anomalies – Prenatal Echocardiography and Neonatal Angio-CT – A Pictorial Essay

Introduction: Fetal echocardiography is a method of choice for diagnosing cardiovascular anomalies prenatally. However, in the majority of cases, the complexity of a defect creates a diagnostic challenge. Moreover, postnatal validation of sonographic findings rarely can be obtained. Nevertheless, the feedback is vital for improving diagnostic capabilities. Thus, the aim of this research was to compare results of prenatal echocardiography with postnatal angio-CT in patients with anomalies of great vessels. Material and methods: We retrospectively compared results of prenatal echocardiography and postnatal angio-CT in 10 patients with selected anomalies of the aortic arch. This was a qualitative analysis, thus discrepancies in recognized anomalies were compared between these two modalities. Results: In 8/10 patient diagnoses were fully consistent. Nevertheless, the tiny caliber of vessels created a diagnostic challenge (e.x. to differentiate the hypoplastic aortic arch from the aortic arch interruption). In the remaining case, the discrepancy was due to a problem with complete visualization of all branches of the aortic arch in prenatal ultrasound. Conclusions: Fetal echocardiography in tertiary center was a reliable method for assessment of great vessels anomalies. However, critically narrow vessels remain a diagnostic challenge and neonatal angio-CT seems to be the method of choice in cases of diagnostic doubts.