Cardiovasc Imaging Asia.  2019 Jan;3(1):8-14. 10.22468/cvia.2018.00227.

Reduced Myocardial Flow Reserve Is Associated with Subendocardial Infarction and Coronary Stenosis in Patients with Coronary Artery Disease: A Perfusion MRI Study

• Manabe O
• Oyama-Manabe N
• Naya M
• Obara M
• Kikuchi Y
• Aikawa T
• Tomiyama Y
• Sugimori H
• Katoh C
• Tamaki N
• Anzai T

• KMID: 2465776
• DOI: http://doi.org/10.22468/cvia.2018.00227

Abstract

OBJECTIVE
Although the relationship between coronary stenosis and myocardial perfusion is well established, little is known regarding the contribution of subendocardial infarction to this relationship. The purpose of this study was to evaluate the effects of obstructive coronary stenosis and subendocardial infarction on myocardial flow reserve (MFR).
MATERIALS AND METHODS
Fifty-four patients with suspected and known coronary artery disease (CAD) who underwent perfusion 3T-MRI and invasive angiography were studied. The time-intensity curves of the left ventricle tissue and cavity were fitted by a single-compartment model to compute myocardial blood flow (MBF). Global MFR and regional MFR were calculated by dividing stress MBF by rest MBF. Myocardial infarction lesions were assessed by late gadolinium enhancement. The effects of obstructive coronary stenosis and subendocardial infarction on the regional MFR were evaluated.
RESULTS
Obstructed vessels (≥70% diameter stenosis for main vessels or ≥50% for left main) were observed in 65 out of 162 vessels. Further analysis demonstrated that MFR in obstructed vessels was significantly lower than that in non-obstructed vessels {1.48 [the interquartile range (IQR) : 1.31-2.03] vs. 1.84 (IQR: 1.44-2.46), p=0.01}. After excluding vessels with transmural infarction (n=19), the MFR for vessels with subendocardial infarction (n=20) was significantly lower than the MFR for non-infarction vessels (n=123) [1.48 (IQR: 1.40-1.79) vs. 1.88 (IQR: 1.41-2.48), p=0.02].
CONCLUSION
Subendocardial infarction in addition to obstructive coronary atherosclerosis might be associated with an impairment of regional MFR in patients with CAD.

Keyword

Myocardial perfusion imaging; Flow reserve; Magnetic resonance imaging; Perfusion; Coronary artery disease

MeSH Terms

Angiography
Constriction, Pathologic
Coronary Artery Disease*
Coronary Stenosis*
Coronary Vessels*
Gadolinium
Heart Ventricles
Humans
Infarction*
Magnetic Resonance Imaging*
Myocardial Infarction
Myocardial Perfusion Imaging
Perfusion*
Gadolinium