4 - iCMR Selective Angiography in Congenital Heart Disease

Thursday, February 13, 2020

3:15 PM – 3:25 PM

Location: Salon J1

Background: Selective angiography aids in navigation and evaluation of the vasculature during standard cardiac catheterization. Recent studies have used MRI for guidance to eliminate radiation exposure during these procedures^1-5. However, the real-time selective evaluation⁶ of flow patterns will be important for these diagnostic procedures to be extended for cardiac interventions and device placement. In this study, we demonstrate the use of selective angiography during MR-guided catheterization in patients with congenital heart disease (CHD).

Methods: 5 pediatric patients with Glenn/Fontan physiology underwent MR-guided catheterization under general anesthesia using a 1.5T Philips Ingenia (Philips Healthcare, Best, NL) and the iSuite platform (Philips Research, Hamburg, Germany)⁷. Selective angiography was used to evaluate pulmonary transit time (SVC injection) to detect pulmonary arteriovenous malformations (PAVMs), and to locate Fontan fenestrations (conduit injection) prior to attempting a Fontan fenestration test occlusion (FFTO). Dilute Gadolinium (Gd) (1/100 Gd/saline) was used both in the balloon-tip catheter for guidance, and for selective injections (50mL) to visualize flow patterns downstream from the catheter tip. T1-weighted spoiled GRE images were acquired to provide distinct signal from the balloon and injected contrast to be overlaid on a previously acquired 3D whole-heart dataset within iSuite. These images were acquired at 4-5fps, TE/TR = 1.2/2.4 ms, 45º flip angle, resolution = 2.5 x 2.5 mm, and a presaturation to suppress tissue signal. A 60mm slice thickness was used to maintain visualization of contrast with complex through-plane motion.

Results: Fig.1 shows a selective SVC injection in a patient with Glenn circulation with normal pulmonary venous return. Fig.2 shows a similar SVC injection in a different patient with Glenn circulation, demonstrating rapid atrial filling due to the presence of pulmonary arteriovenous malformations (AVMs), which were confirmed on standard x-ray angiography. Fig.3 shows a conduit injection to better define Fontan fenestration location prior to FFTO.

Conclusion: The proposed T1-overlay approach provides distinct signal from the catheter and injected contrast while maintaining a high-resolution roadmap of the anatomy with T2/T1 contrast. Although thick 2D imaging slabs cannot resolve through-plane motion of the contrast, they allow a much higher frame rate than what can be achieved with a 3D acquisition. Additionally, the iSuite platform allows imaging from multiple orientations to better understand the complex 3D flow patterns in the heart. In conclusion, we have demonstrated radiation-free real-time selective angiography using the iSuite platform. This technique provides real-time visualization of selective injections that interventionalists are accustomed to with x-ray fluoroscopy.

Primary Author(s)

JG

Joshua S. Greer, PhD

Post-Doc
The University of Texas Southwestern Medical Center

Disclosure: Disclosure information not submitted.

Co-Author(s)

Yousef Arar, MD

Pediatric Cardiology Fellow
The University of Texas Southwestern Medical Center

Disclosure: Disclosure information not submitted.
Vasu D. Gooty, MD

Assistant Professor
LeBonheur Children's Hospital; University of Tennessee Health Sciences

Disclosure: Disclosure information not submitted.
Daniel A. Castellanos, MD

Cardiac MRI & CT Fellow
UT Southwestern Medical Center

Disclosure: Disclosure information not submitted.
SW

Steffen Weiss, PhD

Philips Research Laboratories

Disclosure: Disclosure information not submitted.
SK

Sascha Krueger, PhD

Philips Research

Disclosure: Disclosure information not submitted.
Gerald Greil, MD, PhD

Division Chief
UT Southwestern

Disclosure: I do not have any relevant financial / non-financial relationships with any proprietary interests.
Suren R. Reddy, MD

Associate Professor - Interventional Cardiology
UT Southwestern Medical Center, Dallas

Disclosure: Nano4Imaging (Individual(s) Involved: Self, Products/Services: MRI compatible Guidewire): Other Financial or Material Support, Support for travel and accomodation for invited talk at a meeting.

Presenting Author(s)

Tarique Hussain, MD, PhD

Associate Professor, Pediatric Cardiology
The University of Texas Southwestern Medical Center

Disclosure: Varyfii Imaging: Stockholder/Ownership Interest (excluding diversified mutual funds)