Journal de radiologie OMICS

Abstrait

Effect of Sublingual Nitro-Glycerine Premedication On Image Analysis of Using 256 Multidetector Computed Tomography Coronary Angiography

Dupouy Jean Patrick, Maher Hakim, Fareed Ahmed, Diaa El Hakim, Ramon Labbe, Vladimir Rubimbura, Gerard Hacquin, Jean Claude Gaux, Mario Auguste, Hossam Mansour and Jean Marc Pernes

Background: Multidetector Computed Coronary Tomography (MDCT) has limited spatial and temporal resolutions. Systematic pre-medication with nitrates may improve coronary MDCT analysis.

Objective: The aim of this study was to evaluate the effect of systematic use of nitroglycerin prior to acquisition using the 256 MDCT on safety, hemodynamics and Image quality.

Method: We prospectively enrolled 72 consecutive patients with probable coronary artery disease who underwent image acquisition using 256 MDCT. Patients were randomized into 2 groups according to sealed envelopes determination; One group (36 patients) received 2 doses of 30 mg of sublingual nitroglycerin prior to acquisition (TNT group) while the other group (36 patients) did not receive the pre-acquisition nitrates (non-TNT group). Hemodynamic parameters were measured in both groups (before and after TNT in the TNT group). Global imaging quality assessment, number of analyzable segments, geometric measurements and contrast attenuation of each segment were performed and compared between the 2 groups.

Results: There was no demographic or clinical difference between the two groups. The use of beta-blockers was similar in both groups. There was a significant decrease of blood pressure without changes in the heart rate in the TNT group compared to the non-TNT group (p<0.002). Global imaging quality assessment was equal in both groups. A better signal-to-noise ratio (SNR) and contrast -to-noise ratio (CNR) were observed in the TNT group for distal and secondary segments. The number of non analyzable segments was higher in non-TNT group (15 segments, corresponding to 3 % vs. 4 segments, corresponding to 1%, p<0.05). Per segment mean diameter and area was greater in TNT group for the main coronary arteries and their secondary segments.

Conclusion: Sublingual nitroglycerin significantly improves coronary arteries geometry analysis, especially in secondary segments, without any adverse hemodynamic side effect, which might improve the coronary CT diagnostic accuracy.