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

Donnie Cameron, Nishat Siddiqi, Christopher J. Neil, Baljit Jagpal, Margaret Bruce, David M. Higgins, Jiabao He, Satnam Singh, Thomas W. Redpath, Michael P. Frenneaux, Dana K. Dawson

Research output: Contribution to journalArticlepeer-review

12 Citations (Scopus)
12 Downloads (Pure)

Abstract

OBJECTIVES: 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 1241ms, 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.

Original languageEnglish
Pages (from-to)279-285
Number of pages7
JournalEuropean Journal of Radiology
Volume85
Issue number1
Early online date23 Oct 2015
DOIs
Publication statusPublished - Jan 2016

Bibliographical note

Acknowledgements
This study was supported by a Medical Research Council UK grant (grant number G0800901), as a sub-study of Nitrites in Acute Myocardial Infarction. Thanks are due to Roger Staff, for invaluable advice regarding receiver operator characteristic analysis.

Keywords

  • acute myocardial infarction
  • magnetic resonance imaging
  • myocardium at risk
  • myocardial oedema
  • microvascular obstruction
  • T1 mapping

Fingerprint

Dive into the research topics of 'T1 mapping for assessment of myocardial injury and microvascular obstruction at one week post myocardial infarction'. Together they form a unique fingerprint.

Cite this