Effect of Nitroglycerin on the Performance of MR Coronary Angiography

Abstract

2 J. MAGN. RESON. IMAGING 2017;45:1419-1428.

Applying Nitroglycerin at Coronary MR Angiography at 1.5 T: Diagnostic Performance of Coronary Vasodilation in Patients with Coronary Artery Disease

“…Many factors affect acquisition time, including heart rate, trigger delay time, acquisition window, and respiratory navigator efficiency. In our study, we acquired the coronary MR angiography acquisition during systole for pre-and post-NTG administration, which was different from previous studies (6,14); we did this out of consideration that the evaluation of coronary vasodilation may be not accurate if a different acquisition phase of the cardiac cycle is used for pre-NTG versus post-NTG or vice versa. As a result, in our study no significant difference was found in navigator efficiency, trigger delay time, and acquisition window; however, the acquisition time of coronary MR angiography was found to be slightly shortened after NTG, which was also different from previous studies (6,14).…”

“…In our study, we acquired the coronary MR angiography acquisition during systole for pre-and post-NTG administration, which was different from previous studies (6,14); we did this out of consideration that the evaluation of coronary vasodilation may be not accurate if a different acquisition phase of the cardiac cycle is used for pre-NTG versus post-NTG or vice versa. As a result, in our study no significant difference was found in navigator efficiency, trigger delay time, and acquisition window; however, the acquisition time of coronary MR angiography was found to be slightly shortened after NTG, which was also different from previous studies (6,14). This may be due to the much larger sample size of our study and that previous studies did not strictly maintain the acquisition window in the same phase of the cardiac cycle for pre-and post-NTG coronary MR angiography.…”

“…For occluded vessels, the distal segments were not analyzed at CAG, although collateral flow existed. nitrate-induced coronary vasodilation has been assessed with coronary MR angiography in previous studies, most of those studies used volume-targeted coronary MR angiography acquisition confined to the limited coverage of a single coronary artery, a technique that is less commonly used in current clinical practice (6,(11)(12)(13). In addition, due to the increase in heart rate after applying NTG, previous studies usually performed pre-and post-NTG coronary MR angiography during different phases of the cardiac cycle (6,9,14), which may affect the accurate assessment of coronary vasodilation.…”

“…Exogenous nitroglycerin (NTG) could induce smooth muscle cell-dependent vasodilation by providing endothelium-independent nitric oxide. Nitrate-induced coronary vasodilation could help improve the visibility of the coronary arteries (5,6). For coronary CT angiography, administration of NTG could help improve diagnostic performance and the visibility of the coronary arteries.…”

Non-contrast coronary magnetic resonance angiography: current frontiers and future horizons

“…In the absence of overt contraindications, the administration of sublingual nitroglycerin (NTG) is recommended to improve luminal visualization in terms of signal-to-noise ratio (SNR), vessel diameter, and vessel sharpness of the coronary MRA [ 47 ]. Heer et al have reported that the significant increase in coronary diameter and visible vessel length observed with sublingual NTG administration result in improved sensitivity, specificity, and diagnostic accuracy for the detection of > 50% coronary stenosis on 1.5 T non-contrast coronary MRA [ 48 ].…”