Adapting Trigger Delays to Heart Rate for Coronary MR Angiography
Wright G, Liu G
University of Toronto
Heart rate variations can reduce both the effectiveness and efficiency of cardiac gating for coronary angiography. Our work explores how heart rate variations can affect cardiac imaging windows and justifies the use of heart rate adaptive trigger delays in a correction scheme. Specifically, the ideal trigger delay is nonlinearly related to the preceding pacing cycle length (RR interval on the ECG) and can be charactized per individual during a prescan exam. With this approach, we anticipate that imaging windows can be extended by approximately 10-20% for a 20bpm increase in heart rate depending on the region of interest.