Susceptibility-sensitive magnetic resonance imaging detects human myocardium supplied by a stenotic coronary artery without a contrast agent

Abstract

For the first time, we could show that myocardial BOLD MRI detects post-stenotic capillary recruitment dependent on coronary artery stenosis.

BOLD cardiovascular magnetic resonance at 3.0 tesla in myocardial ischemia

“…Our findings were consistent with previous reports by Wacker et al and Niemi et al [11,18], but somewhat contrasted the results by Friedrich et al [12] even demonstrating a signal decrease during vasodilator stress in myocardial territories supplied by coronary arteries with >75% luminal narrowing.…”

“…BOLD imaging represents a promising alternative to first-pass CMR perfusion techniques, which rely on the application of exogenous contrast agents. BOLD imaging allows to directly assess the myocardial oxygenation status taking advantage of the paramagnetic properties of intravascular deoxyhemoglobin [11]. During adenosine stress, myocardial segments being supplied by normal coronary arteries show an increased oxygen content while deoxyhemoglobin concentration is low resulting in a higher signal on T2*- or T2-weighted images.…”

“…Importantly, the current study population consisted of consecutive patients with a high proportion of known CAD and prior myocardial infarctions but such patients were usually not considered in previous studies [11,12,21]. However, a direct comparison to first pass CMR perfusion or SPECT imaging would have been desirable and may be considered a limitation of the present study.…”

“…Thus, BOLD CMR directly reflects myocardial oxygenation status [9,10]. Coronary artery stenosis leads to poststenotic microvascular dilatation in a compensatory effort to maintain sufficient myocardial oxygen supply [11] and blood-oxygen level dependent imaging has been successfully introduced to determine capillary reserve [12,13]. …”

“…However, data on myocardial BOLD CMR during vasodilator stress in patients with coronary artery disease (CAD) is limited to experimental studies [13-15] and small patient populations [11,12]. The main challenge was low signal intensity differences between normal and pathologic areas of myocardium at 1.5T, and therefore BOLD CMR at 3T may benefit from the inherently higher signal-to-noise ratio (SNR).…”