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Updated: May 6, 2026
Multimodality Diagnosis of Mesenteric Ischemia
Published on: July 21, 2023
Perfusion versus function: the ischemic cascade in demand ischemia: implications of single-vessel versus multivessel
Howard Leong-Poi1, Se-Joong Rim, D Elizabeth Le
1Cardiac Imaging Center, Cardiovascular Division, University of Virginia School of Medicine, Charlottesville, Va, USA.
Insights
In demand ischemia, abnormal heart perfusion occurs before functional changes. This perfusion abnormality is more widespread than functional changes and is more pronounced in single-vessel stenosis (SVS) than multivessel stenosis (MVS).
Area of Science:
- Cardiovascular Physiology
- Echocardiography
- Ischemic Heart Disease
Background:
- Demand ischemia can lead to abnormalities in myocardial perfusion and function.
- Understanding the sequence and spatial extent of these abnormalities is crucial for diagnosing coronary artery stenosis.
- Differentiating between single-vessel stenosis (SVS) and multivessel stenosis (MVS) may influence the presentation of ischemic changes.
Purpose of the Study:
- To investigate the temporal and spatial relationship between abnormal myocardial perfusion and function during demand ischemia.
- To compare these relationships in the context of single-vessel stenosis (SVS) versus multivessel stenosis (MVS).
- To determine if perfusion abnormalities precede functional abnormalities and their relative spatial extents.
Main Methods:
- Nine dogs underwent either SVS or MVS placement with varying stenosis severity.
- Dobutamine infusion was used to induce demand ischemia.
- Myocardial perfusion (using myocardial contrast echocardiography) and wall thickening (as a measure of function) were assessed at different dobutamine doses.
Main Results:
- Abnormal perfusion was detected at lower dobutamine doses than abnormal wall thickening in SVS.
- The spatial extent of perfusion abnormalities was generally greater than that of functional abnormalities.
- The spatiotemporal discordance between perfusion and function was less pronounced in MVS compared to SVS.
Conclusions:
- The findings support the concept of an ischemic cascade where perfusion deficits occur before functional impairments.
- Abnormal perfusion is a more sensitive indicator of coronary stenosis than abnormal function.
- Dobutamine echocardiography demonstrates higher sensitivity for MVS detection compared to SVS due to distinct patterns of ischemic changes.
Background:
We hypothesized that during demand ischemia, abnormal perfusion will precede abnormal function, the spatial extent of perfusion abnormality will be greater than that of functional abnormality, and the spatiotemporal disparity between abnormal perfusion and abnormal function will be more marked in the presence of single-vessel stenosis (SVS) versus multivessel stenosis (MVS).
Methods And Results:
Nine dogs each underwent either SVS or MVS placement. These noncritical stenoses were classified as mild, moderate, or severe on the basis of the transstenotic pressure gradient (10 to 14, 15 to 20, or >20 mm Hg). Dobutamine was infused starting at 10 and reaching 40 microg/kg(-1) x min(-1). Wall thickening (WT) and myocardial perfusion (myocardial contrast echocardiography) were assessed at each stage. Resting perfusion and function were normal in all dogs. In SVS, abnormal perfusion (delayed rate of microbubble replenishment) was seen at the lowest dose of dobutamine irrespective of the stenosis severity, whereas WT abnormality was seen only at high doses of dobutamine and was influenced by the stenosis severity. The spatial extent of abnormal perfusion exceeded that of WT abnormality at all but the highest dobutamine dose. This spatiotemporal discordance between abnormal perfusion and function was significantly less in MVS, where it was possible to identify separate regions with abnormal function at lower doses of dobutamine.
Conclusions:
These data support the occurrence of the ischemic cascade during demand ischemia. They also explain the higher sensitivity of abnormal perfusion compared with abnormal function for the detection of coronary stenosis as well as the higher sensitivity of dobutamine echocardiography for MVS compared with SVS.
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