Whole heart coronary imaging with flexible acquisition window and trigger delay

Area of Science:

• Cardiovascular Imaging
• Medical Physics
• Radiology

Background:

• Coronary MRI timing relies on trigger delays from scout scans.
• Heart rate variability can cause timing inaccuracies in coronary MRI.
• Standard trigger delays may not capture minimal motion periods for all coronary segments.

Purpose of the Study:

• To develop a whole-heart coronary MRI approach with flexible trigger delay selection.
• To address coronary motion inaccuracies through interactive temporal window selection.
• To improve the visualization and sharpness of coronary arteries in MRI.

Main Methods:

• Developed an ECG-gated, k-space segmented 3D radial stack-of-stars sequence.
• Implemented an enlarged acquisition window (166-220 ms) prior to scout-derived trigger delay.
• Utilized an interactive platform for selecting minimal motion temporal subsets for reconstruction.

Main Results:

• Manual adjustment of the acquisition window recovered visualization of previously unseen right coronary artery regions.
• Sharpness scores significantly improved across all evaluated coronary artery regions.
• The proposed method demonstrated feasibility in tailoring reconstructions for specific coronary branches.

Conclusions:

• The novel whole-heart coronary MRI approach enables interactive optimization of trigger delay timing.
• This method enhances image quality and diagnostic potential for coronary artery visualization.
• Flexible window selection overcomes limitations of standard trigger delay methods in coronary MRI.