Improved catheter tracking during cardiovascular magnetic resonance-guided cardiac catheterization using overlay...

Area of Science:

• Cardiovascular Imaging
• Medical Devices
• Interventional Cardiology

Background:

• Cardiovascular magnetic resonance (CMR)-guided cardiac catheterization offers functional data without ionizing radiation.
• Current real-time imaging sequences for catheter guidance have limited resolution and anatomical detail.
• Passive catheter tracking is needed to improve visualization and guidance accuracy.

Purpose of the Study:

• To introduce and evaluate a novel passive catheter tracking approach for CMR-guided cardiac catheterization.
• To enhance real-time visualization of the catheter and cardiac anatomy during the procedure.
• To assess the feasibility of iCMR selective angiography for blood flow dynamics evaluation.

Main Methods:

• A T1-overlay technique was developed using a T1-weighted sequence overlaid on a 3D dataset in real-time.
• Sixty patients with congenital heart disease underwent CMR-guided cardiac catheterization using the T1-overlay technique on a 1.5T CMR scanner.
• Catheter visualization time was compared between T1-overlay and conventional balanced steady state free precession (bSSFP) sequences.

Main Results:

• The T1-overlay approach significantly increased catheter tip visualization time compared to bSSFP.
• Cardiologists rated T1-overlay images higher for contrast, anatomy visualization, and overall suitability.
• iCMR selective angiography using T1-overlay accurately estimated pulmonary transit time, validated against x-ray fluoroscopy.

Conclusions:

• The T1-overlay technique effectively improves passive catheter tracking and cardiac anatomy visualization during CMR-guided procedures.
• This method enhances the time the catheter tip is visible, aiding procedural guidance.
• iCMR selective angiography is feasible for measuring pulmonary transit time, offering an alternative to fluoroscopy.