T₁ mapping for assessment of myocardial injury and microvascular obstruction at one week post myocardial infarction

详细信息    查看全文

• 作者：Donnie Cameron^a ; ^{d.cameron.09@aberdeen.ac.uk" class="auth_mail" title="E-mail the corresponding author} ; ^{donnie.cameron@nih.gov" class="auth_mail" title="E-mail the corresponding author} ; Nishat Siddiqi^a ; ^{n.siddiqi@abdn.ac.uk" class="auth_mail" title="E-mail the corresponding author} ; Christopher J. Neil^a ; ^{ctop1@me.com" class="auth_mail" title="E-mail the corresponding author} ; Baljit Jagpal^a ; ^{b.jagpal@abdn.ac.uk" class="auth_mail" title="E-mail the corresponding author} ; Margaret Bruce^a ; ^{maggie.bruce2@nhs.net" class="auth_mail" title="E-mail the corresponding author} ; David M. Higgins^b ; ^{David.Higgins@philips.com" class="auth_mail" title="E-mail the corresponding author} ; Jiabao He^a ; ^{jiabao.he@abdn.ac.uk" class="auth_mail" title="E-mail the corresponding author} ; Satnam Singh^a ; ^{s.singh@abdn.ac.uk" class="auth_mail" title="E-mail the corresponding author} ; Thomas W. Redpath^a ; ^{t.redpath@abdn.ac.uk" class="auth_mail" title="E-mail the corresponding author} ; Michael P. Frenneaux^a ; ^{m.p.frenneaux@abdn.ac.uk" class="auth_mail" title="E-mail the corresponding author} ; Dana K. Dawson^a ; ^{dana.dawson@abdn.ac.uk" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Acute myocardial infarction ; Magnetic resonance imaging ; Myocardium at risk ; Myocardial oedema ; Microvascular obstruction ; T1 mapping
• 刊名：European Journal of Radiology
• 出版年：2016
• 出版时间：January 2016
• 年：2016
• 卷：85
• 期：1
• 页码：279-285
• 全文大小：2092 K

文摘

To compare 3T T₁ mapping to conventional T₂-weighted (T₂W) imaging for delineating myocardial oedema one week after ST-elevation myocardial infarction (STEMI), and to explore the confounding effects of microvascular obstruction (MVO) on each technique.

Methods

T₂W spectral attenuated inversion recovery and native T₁ mapping were applied in 10 healthy volunteers and 62 STEMI patients, and late gadolinium enhancement was included for infarct localisation at 1 week and at 6 months post-STEMI. Segmental T₁ values and T₂W signal intensity ratios were calculated; oedema volumes and salvage indices were determined in patients using image thresholding—a receiver operator characteristic (ROC) derived T₁ threshold, and a 2SD T₂W threshold; and the results were compared between patients with/without MVO (n = 35/27).

Results

Native T₁ mapping delineated oedema with significantly better discriminatory power than T₂W—as indicated by ROC analysis (area-under-the-curve, AUC = 0.89 versus 0.83, p = 0.009; and sensitivity/specificity = 83/83% versus 73/73%). The optimal ROC threshold derived for T₁ mapping was 1241 ms, which gave significantly larger oedema volumes than 2SD T₂W (p = 0.006); with this threshold, patients with and without MVO showed similar oedema volumes, but patients with MVO had significantly poorer salvage indices (p < 0.05) than those without. Neither method was significantly affected by MVO, the volume of which was seen to increase exponentially with infarct size.

Conclusions

Native T₁ mapping at 3T can delineate oedema one week post-STEMI, showing larger oedema volumes and better discriminatory power than T₂W imaging, and it is suitable for quantitative thresholding. Both techniques are robust against MVO-related magnetic susceptibility.