Segmental redistribution of myocardial blood flow after coronary sinus reducer implantation demonstrated by quantitative perfusion cardiovascular magnetic resonance
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Background
The coronary sinus reducer (CSR) is a novel percutaneous treatment for patients with refractory angina. Increasing evidence supports its clinical efficacy in patients with advanced epicardial coronary artery disease. However, its mechanism of action and its effects on myocardial perfusion remain undefined. Using quantitative stress perfusion cardiovascular magnetic resonance (CMR), this study assessed changes in myocardial perfusion in patients with refractory angina undergoing CSR implantation.
Methods
This single-center retrospective observational cohort study included 16 patients. Rest and adenosine stress perfusion CMR was performed before and at median 5 months after CSR implantation. Perfusion images were acquired using a dual-sequence quantitative protocol with automated generation of myocardial blood flow (MBF; mL/min/g). In addition to visual assessment of ischemic segments, changes in absolute MBF across myocardial segments and between myocardial layers were analyzed.
Results
A high proportion of myocardial segments had visually adjudicated ischemia at baseline (208 out of 254: 81.9%), which significantly reduced after CSR implantation (175 out of 254: 68.9%; P = 0.001). There were no changes in global MBF or strain values. Changes in myocardial perfusion reserve (MPR) correlated with baseline MPR with more ischemic segments at baseline improving to a greater extent at follow-up. Similar patterns were observed in both the left and right coronary artery territories. Changes in endocardial/epicardial MBF ratio at stress were similarly dependent on baseline values.
Conclusion
In patients with refractory angina undergoing CSR implantation, quantitative stress perfusion CMR demonstrated redistribution of myocardial perfusion across segments, from less ischemic to more ischemic myocardium, and across myocardial layers with greatest improvements in endocardial perfusion observed in the most ischemic myocardium. Further studies are needed to validate the different patterns of MBF redistribution that may occur after CSR implantation and correlate with clinical outcomes.
The coronary sinus reducer (CSR) is a novel percutaneous treatment for patients with refractory angina. Increasing evidence supports its clinical efficacy in patients with advanced epicardial coronary artery disease. However, its mechanism of action and its effects on myocardial perfusion remain undefined. Using quantitative stress perfusion cardiovascular magnetic resonance (CMR), this study assessed changes in myocardial perfusion in patients with refractory angina undergoing CSR implantation.
Methods
This single-center retrospective observational cohort study included 16 patients. Rest and adenosine stress perfusion CMR was performed before and at median 5 months after CSR implantation. Perfusion images were acquired using a dual-sequence quantitative protocol with automated generation of myocardial blood flow (MBF; mL/min/g). In addition to visual assessment of ischemic segments, changes in absolute MBF across myocardial segments and between myocardial layers were analyzed.
Results
A high proportion of myocardial segments had visually adjudicated ischemia at baseline (208 out of 254: 81.9%), which significantly reduced after CSR implantation (175 out of 254: 68.9%; P = 0.001). There were no changes in global MBF or strain values. Changes in myocardial perfusion reserve (MPR) correlated with baseline MPR with more ischemic segments at baseline improving to a greater extent at follow-up. Similar patterns were observed in both the left and right coronary artery territories. Changes in endocardial/epicardial MBF ratio at stress were similarly dependent on baseline values.
Conclusion
In patients with refractory angina undergoing CSR implantation, quantitative stress perfusion CMR demonstrated redistribution of myocardial perfusion across segments, from less ischemic to more ischemic myocardium, and across myocardial layers with greatest improvements in endocardial perfusion observed in the most ischemic myocardium. Further studies are needed to validate the different patterns of MBF redistribution that may occur after CSR implantation and correlate with clinical outcomes.
Date Issued
2025-06-01
Date Acceptance
2025-02-21
Citation
Journal of Cardiovascular Magnetic Resonance, 2025, 27 (1)
ISSN
1097-6647
Publisher
Elsevier
Journal / Book Title
Journal of Cardiovascular Magnetic Resonance
Volume
27
Issue
1
Copyright Statement
© 2025 The Author(s). Published by Elsevier Inc. on behalf of Society for Cardiovascular Magnetic Resonance. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
License URL
Identifier
10.1016/j.jocmr.2025.101868
Subjects
Refractory angina Angina pectoris Coronary sinus reducer Cardiovascular magnetic resonance imaging Quantitative perfusion Myocardial blood flow CABG, coronary artery bypass grafting
CAD, coronary artery disease
CCS, Canadian Cardiovascular Society
COSIRA trial, coronary sinus reducer for treatment of refractory angina trial
CMR, cardiac magnetic resonance
CSR, coronary sinus reducer
IQR, interquartile range
LGE, late gadolinium enhancement
MBF, myocardial blood flow
MPR, myocardial perfusion reserve
MPRI, myocardial perfusion reserve index
ORBITA-COSMIC trial, coronary sinus reducer objective impact on symptoms, MRI ischemia and microvascular resistance trial
PCI, percutaneous coronary intervention
PET, positron emission tomography
RATIOSTRESS, endocardial/epicardial ratio at stress
REMEDY-PILOT trial, coronary sinus reducer implantation in patients with ischemia and non-obstructed coronary arteries and coronary microvascular dysfunction trial
Publication Status
Published
Article Number
101868
Date Publish Online
2025-02-26