Magnetic resonance versus radionuclide pharmacological stress perfusion imaging for flow-limiting stenoses of varying severity.

Published

Journal Article

BACKGROUND: Although magnetic resonance first-pass imaging (MRFP) has potential advantages in pharmacological stress perfusion imaging, direct comparisons of current MRFP and established radionuclide techniques are not available. METHODS AND RESULTS: Graded regional differences in coronary flow were produced during global coronary vasodilation in chronically instrumented dogs by partially occluding the left circumflex artery. Regional differences in full-thickness flow quantified using microspheres were compared with regional differences obtained with MRFP and radionuclide SPECT imaging (99mTc-sestamibi and 201Tl). Relative regional flows (RRFs) derived from the initial areas under MRFP signal intensity-time curves were linearly related to reference microsphere RRFs over the full range of vasodilation (y=0.93x+4.3; r2=0.77). Relationships between 99mTc-sestamibi and 201Tl RRFs and microsphere RRFs were curvilinear, plateauing as flows increased. The high spatial resolution of the MRI enabled transmural flow to be evaluated in 3 to 5 layers across the myocardial wall. Reductions in subendocardial flow were visually apparent in MRFP images for > or =50% reductions in full-thickness flow. Endocardial-to-epicardial gradients in MRFP flow increased progressively with stenosis severity, whereas transmural flow patterns in remote normally perfused myocardium remained normal. Flow reductions of > or =50% not identified by radionuclide imaging were apparent in MRFP full-thickness and transmural analyses. CONCLUSIONS: High-resolution MRFP can identify regional reductions in full-thickness myocardial blood flow during global coronary vasodilation over a wider range than current SPECT imaging. Transmural flow gradients can also be identified; their magnitude increases progressively as flow limitations become more severe and endocardial flow is compromised increasingly.

Full Text

Duke Authors

Cited Authors

  • Lee, DC; Simonetti, OP; Harris, KR; Holly, TA; Judd, RM; Wu, E; Klocke, FJ

Published Date

  • July 6, 2004

Published In

Volume / Issue

  • 110 / 1

Start / End Page

  • 58 - 65

PubMed ID

  • 15210596

Pubmed Central ID

  • 15210596

Electronic International Standard Serial Number (EISSN)

  • 1524-4539

Digital Object Identifier (DOI)

  • 10.1161/01.CIR.0000133389.48487.B6

Language

  • eng

Conference Location

  • United States