Volume 15 Supplement 1
Usefulness of semi-quantification of ischemic myocardium after adenosine stress magnetic resonance
© Monti et al; licensee BioMed Central Ltd. 2013
Published: 30 January 2013
Adenosine stress MR shows high sensitivity and intermediate-to-high specificity; therefore, there is a number of false positive patients that is referred to useless coronary angiography studies after a positive adenosine stress MR. We sought to verify whether the (semi) quantification of the amount of ischemic myocardium can improve the management of patients after a positive adenosine stress MR study. According to previous nuclear medicine evidence, we defined a 10% LV mass cut-off for the diagnosis of clinically relevant ischemia.
80 MR studies were classified as positive or negative according to the presence or absence of a reversible perfusion defect ("old approach"). We re-analyzed the perfusion studies dividing each one of the 16 AHA segment of the 3 perfusion slices in 2 similar sub-segments ( subepicardial and subendocardial): each one of the resulting 32 segment represent about 3% of the myocardial mass. We re-defined ("new approach") as ischemic the patients with > 3 subsegments (>10% of LV mass) with reversible lesions, and as non-ischemic the patients with 3 or less positive subsegments. Patients were classified as affected by clinically relevant ischemia if the post-adenosineMR coronary angiography confirmed coronary lesions > 50%, and non-affected if the angio was negative and/or no MACE were observed after a > 6 months follow-up.
Mean age 60.7 years old. Mean follow-up = 18 months (5-37). Pre-test prevalence of CHD: 64%. Prevalence of clinically relevant ischemia = 17.5%. With the old approach we obtained a sensitivity and specificity of 92.9% and 72.7 respectively. With the new approach we obtained a sensitivity and specificity of 85.7% and 90.9% respectively. Global accuracy of the stress MR exam increased from 76.2 to 90%.
A visual semi-quantification of the ischemic myocardium improves patient management after a positive adenosine stress MR study.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.