Author + information
- Received July 24, 2018
- Revision received October 23, 2018
- Accepted October 23, 2018
- Published online September 2, 2019.
- Alessandra Borlotti, PhDa,
- Michael Jerosch-Herold, PhDb,
- Dan Liu, PhDa,
- Dafne Viliani, MDa,
- Alessia Bracco, MDa,
- Mohammad Alkhalil, BSC, MDa,
- Giovanni Luigi De Maria, MDa,
- OxAMI Study Investigators,
- Keith M. Channon, MDc,
- Adrian P. Banning, MBBS, MDc,
- Robin P. Choudhury, DMa,
- Stefan Neubauer, MDa,
- Rajesh K. Kharbanda, MD, PhDc and
- Erica Dall’Armellina, MD, DPhila,∗ ()
- aDivision of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
- bDepartment of Radiology, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
- cOxford Heart Centre, John Radcliffe Hospital, Oxford, United Kingdom
- ↵∗Address for correspondence:
Dr. Erica Dall’Armellina, Leeds Institute of Cardiovascular and Metabolic Medicine, Division of Biomedical Imaging, University of Leeds, LIGHT Building, Clarendon Way, Leeds LS2 9JT, United Kingdom.
Objectives This study sought to investigate the clinical utility and the predictive relevance of absolute rest myocardial blood flow (MBF) by cardiac magnetic resonance (CMR) in acute myocardial infarction.
Background Microvascular obstruction (MVO) remains one of the worst prognostic factors in patients with reperfused ST-segment elevation myocardial infarction (STEMI). Clinical trials have focused on cardioprotective strategies to maintain microvascular functionality, but there is a need for a noninvasive test to determine their efficacy.
Methods A total of 64 STEMI patients post–primary percutaneous coronary intervention underwent 3-T CMR scans acutely and at 6 months (6M). The protocol included cine function, T2-weighted edema imaging, pre-contrast T1 mapping, rest first-pass perfusion, and late gadolinium enhancement imaging. Segmental MBF, corrected for rate pressure product (MBFcor), was quantified in remote, edematous, and infarcted myocardium.
Results Acute MBFcor was significantly reduced in infarcted myocardium compared with remote MBF (MBFinfarct 0.76 ± 0.20 ml/min/g vs. MBFremote 1.02 ± 0.21 ml/min/g, p < 0.001), but it significantly increased at 6M (MBFinfarct 0.76 ± 0.20 ml/min/g acute vs. 0.85 ± 0.22 ml/min/g at 6M, p < 0.001). On a segmental basis, acute MBFcor had incremental prognostic value for infarct size at 6M (odds of no LGE at 6M increased by 1.4:1 [p < 0.001] for each 0.1 ml/min/g increase of acute MBFcor) and functional recovery (odds of wall thickening >45% at 6M increased by 1.38:1 [p < 0.001] for each 0.1 ml/min/g increase of acute MBFcor). In subjects with coronary flow reserve >2 or index of myocardial resistance <40, acute MBF was associated with long-term functional recovery and was an independent predictor of infarct size reduction.
Conclusions Acute MBF by CMR could represent a novel quantitative imaging biomarker of microvascular reversibility, and it could be used to identify patients who may benefit from more intensive or novel therapies.
Dr. Dall’Armellina is currently affiliated with the Leeds Institute of Cardiovascular and Metabolic Medicine, Division of Biomedical Imaging, University of Leeds, Leeds, United Kingdom. This work is supported by the British Heart Foundation (BHF) and the Oxford National Institute for Health Research Biomedical Research Centre. Profs. Channon, Choudhury, and Neubauer acknowledge support from the Oxford British Heart Foundation Centre of Research Excellence. Dr. Dall’Armellina is a BHF Intermediate Clinical Research Fellow. The authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received July 24, 2018.
- Revision received October 23, 2018.
- Accepted October 23, 2018.
- 2019 The Authors