Coronary MR angiography: Selection of acquisition window of minimal cardiac motion with electrocardiography-triggered navigator cardiac motion prescanning-initial results

The authors developed an electrocardiography-triggered M-mode navigator-ech o technique to help monitor cardiac motion and identify the period of minim al cardiac motion in the cardiac cycle. Coronary magnetic resonance angiogr aphy was performed in eight healthy adult volunteers and one patient with h eart disease. To minimize cardiac motion effects, trigger delays were estim ated with the navigator-echo technique and two empirical formulas. The qual ity of images obtained with the different delay times was compared for clar ity of depiction of the coronary arteries. Image quality was best with the delay calculated with the navigator-echo technique.