Design of a Low-Cost, Self-Adaptive and MRI-Compatible Cardiac Gating System.

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Cardiovascular Technology

Background:

• Cardiac gating synchronizes medical scans with cardiac activity for accurate physiological measurements and artifact-free imaging.
• Existing methods face limitations in complex MRI environments and adaptability to varying heart rates.
• Accurate gating is crucial for disease diagnosis and advanced applications like medical microrobot control.

Purpose of the Study:

• To develop and validate a low-cost, self-adaptive, MRI-compatible cardiac gating system.
• To assess the system's performance using blood pressure waveform analysis.
• To demonstrate the system's efficacy in high-resolution 4D flow MRI acquisitions.

Main Methods:

• The proposed system monitors and analyzes blood pressure waveforms for cardiac cycle detection.
• Experiments were conducted in vitro and in vivo using two living pigs.
• Four-dimensional (4D) flow magnetic resonance imaging (MRI) and two-dimensional phase-contrast (2D-PC) sequences were employed for testing.

Main Results:

• The system demonstrated stable cardiac synchronicity and excellent MRI compatibility, handling electromagnetic interference and heart rate variations.
• High-resolution 4D flow imaging was successfully acquired both in vitro and in vivo.
• Achieved a 0% false trigger rate, outperforming existing cardiac gating methods, with measurement differences of ≤ 21% between 2D and 4D data.

Conclusions:

• The developed system provides a stable, accurate trigger signal based on pressure waveforms, with superior MRI compatibility.
• Its 0% false trigger rate and adaptability make it suitable for applications where previous gating methods were challenging.
• This innovation facilitates improved diagnostic capabilities and novel applications in medical imaging.