Quantification of myocardial blood flow using non-electrocardiogram-triggered MRI with three-slice coverage

Area of Science:

• Cardiovascular Magnetic Resonance Imaging
• Myocardial Perfusion Quantification

Background:

• Accurate myocardial perfusion quantification relies on electrocardiogram (ECG) triggering.
• Measuring myocardial blood flow (MBF) in patients with arrhythmias or poor ECGs is challenging with conventional MRI.

Purpose of the Study:

• To demonstrate the feasibility of a non-ECG-triggered method for MBF measurement.
• To achieve clinically useful three-slice ventricular coverage for MBF assessment in healthy volunteers.

Main Methods:

• Utilized a saturation recovery magnetization-prepared gradient recalled echo acquisition with a slice-interleaved radial trajectory for retrospective triggering.
• Generated the arterial input function using a beat-by-beat T1 estimation method.
• Validated against ECG-triggered dual-bolus technique in 10 volunteers and demonstrated under adenosine stress in 12 volunteers.

Main Results:

• The non-ECG-triggered method produced MBF measurements comparable to the conventional ECG-triggered technique.
• Mean myocardial perfusion reserve values were consistent with published literature.

Conclusions:

• Developed a novel non-ECG-triggered quantitative perfusion imaging method.
• Demonstrated feasibility and comparable MBF quantification to conventional methods.
• The technique is suitable for stress imaging applications.