Improved passive catheter tracking with positive contrast for CMR-guided cardiac catheterization using partial saturation (pSAT)

• Published in: Journal of cardiovascular magnetic resonance Vol. 19; no. 1; pp. 60 - 9
• Main Authors: Velasco Forte, Mari Nieves, Pushparajah, Kuberan, Schaeffter, Tobias, Valverde Perez, Israel, Rhode, Kawal, Ruijsink, Bram, Alhrishy, Mazen, Byrne, Nicholas, Chiribiri, Amedeo, Ismail, Tevfik, Hussain, Tarique, Razavi, Reza, Roujol, Sébastien
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 15.08.2017; BioMed Central Ltd; BioMed Central; Elsevier
• Subjects: Adolescent; Adult; Cardiac catheterization; Cardiac Catheterization - instrumentation; Cardiac Catheters; Care and treatment; Case-Control Studies; Congenital heart disease; Contrast Media - administration & dosage; Device tracking; Diagnosis; Feasibility Studies; Female; Heart Defects, Congenital - diagnosis; Heart Defects, Congenital - physiopathology; Heart Defects, Congenital - therapy; Humans; Image Interpretation, Computer-Assisted; Interventional CMR; Magnetic resonance imaging; Magnetic Resonance Imaging, Interventional; Male; Meglumine - administration & dosage; Organometallic Compounds - administration & dosage; Predictive Value of Tests; Technical Notes; Cardiac catheterization; Congenital heart disease; Device tracking; Interventional CMR
• ISSN: 1097-6647; 1532-429X; 1532-429X
• DOI: 10.1186/s12968-017-0368-0

Cardiac catheterization is a common procedure in patients with congenital heart disease (CHD). Although cardiovascular magnetic resonance imaging (CMR) represents a promising alternative approach to fluoroscopy guidance, simultaneous high contrast visualization of catheter, soft tissue and the blood pool remains challenging. In this study, a novel passive tracking technique is proposed for enhanced positive contrast visualization of gadolinium-filled balloon catheters using partial saturation (pSAT) magnetization preparation. The proposed pSAT sequence uses a single shot acquisition with balanced steady-state free precession (bSSFP) readout preceded by a partial saturation pre-pulse. This technique was initially evaluated in five healthy subjects. The pSAT sequence was compared to conventional bSSFP images acquired with (SAT) and without (Non-SAT) saturation pre-pulse. Signal-to-noise ratio (SNR) of the catheter balloon, blood and myocardium and the corresponding contrast-to-noise ratio (CNR) are reported. Subjective assessment of image suitability for CMR-guidance and ideal pSAT angle was performed by three cardiologists. The feasibility of the pSAT sequence is demonstrated in two adult patients undergoing CMR-guided cardiac catheterization. The proposed pSAT approach provided better catheter balloon/blood contrast and catheter balloon/myocardium contrast than conventional Non-SAT sequences. It also resulted in better blood and myocardium SNR than SAT sequences. When averaged over all volunteers, images acquired with a pSAT angle of 20° to 40° enabled simultaneous visualization of the catheter balloon and the cardiovascular anatomy (blood and myocardium) and were found suitable for CMR-guidance in >93% of cases. The pSAT sequence was successfully used in two patients undergoing CMR-guided diagnostic cardiac catheterization. The proposed pSAT sequence offers real-time, simultaneous, enhanced contrast visualization of the catheter balloon, soft tissues and blood. This technique provides improved passive tracking capabilities during CMR-guided catheterization in patients.