Related Experiment Video
Updated: Jan 19, 2026
Author Spotlight: Improved Localization and Monitoring of Coronary Flow Reserve Using Modified PLAX View in Mice
Published on: August 25, 2023
Stress Myocardial Blood Flow Ratio by Dynamic CT Perfusion Identifies Hemodynamically Significant CAD
Junjie Yang1, Guanhua Dou2, Bai He2
1Department of Cardiology, Chinese PLA General Hospital, Beijing, China; Cardiovascular Imaging Program, Department of Medicine and Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts; Master Program of Medical Science and Clinical Investigation, Harvard Medical School, Boston, Massachusetts.
Insights
Stress myocardial blood flow ratio (SFR) accurately detects significant coronary artery stenosis. This novel parameter derived from computed tomographic perfusion (CTP) improves diagnostic accuracy for identifying flow-limiting lesions.
Area of Science:
- Cardiovascular Imaging
- Radiology
- Cardiac CT
Background:
- Cardiac computed tomography (CT) offers combined assessment of coronary artery anatomy and myocardial ischemia.
- A comprehensive protocol includes coronary computed tomographic angiography (CTA) and computed tomographic perfusion (CTP).
Purpose of the Study:
- To evaluate the diagnostic accuracy of stress myocardial blood flow ratio (SFR) for detecting hemodynamically significant coronary stenosis.
- SFR is a novel parameter derived from stress dynamic CTP.
Main Methods:
- Prospective enrollment of patients undergoing invasive angiography for chest pain.
- Stress dynamic CTP and coronary CTA were performed using a dual-source CT system.
- Fractional flow reserve (FFR) served as the reference standard for hemodynamically significant stenosis (FFR ≤0.80).
Main Results:
- SFR was significantly lower in vessels with hemodynamically significant lesions (0.66 ± 0.14 vs. 0.90 ± 0.07, p < 0.01).
- SFR increased specificity for detecting ischemia (91%) compared to CTA alone (43%), with a sensitivity of 62%.
- The combination of CTA (≥50% stenosis) and SFR yielded an AUC of 0.91, superior to hyperemic myocardial blood flow (AUC = 0.79, p = 0.013).
Conclusions:
- Stress myocardial blood flow ratio (SFR) calculated by dynamic CTP is a novel and accurate method.
- SFR effectively identifies flow-limiting coronary stenosis.
- This technique enhances the diagnostic capability of cardiac CT in evaluating coronary artery disease.
Objectives:
The aim of this study was to evaluate the diagnostic accuracy of stress myocardial blood flow ratio (SFR), a novel parameter derived from stress dynamic computed tomographic perfusion (CTP), for the detection of hemodynamically significant coronary stenosis.
Background:
A comprehensive cardiac computed tomographic protocol combining coronary computed tomographic angiography (CTA) and CTP can provide a simultaneous assessment of both coronary artery anatomy and ischemia.
Methods:
Patients with chest pain scheduled for invasive angiography were prospectively enrolled in this study. Stress dynamic CTP was performed followed by coronary CTA using a second-generation dual-source computed tomographic system. At subsequent invasive angiography, fractional flow reserve was performed to identify hemodynamically significant stenosis. For each coronary territory, SFR was defined as the ratio of hyperemic myocardial blood flow (MBF) in an artery with stenosis to hyperemic MBF in a nondiseased artery. The diagnostic accuracy of SFR to identify hemodynamically significant stenosis was determined against the reference standard of invasive fractional flow reserve ≤0.80.
Results:
A total of 82 patients (mean age 58.5 ± 10 years) with 101 vessels with either 1- or 2-vessel disease were included. By FFR, 48 (47.5%) vessels were deemed hemodynamically significant. Hyperemic MBF and SFR were lower for vessels with hemodynamically significant lesions (95.1 ± 32.4 ml/100 ml/min vs. 142.5 ± 31.2 ml/100 ml/min and 0.66 ± 0.14 vs. 0.90 ± 0.07, respectively; p < 0.01 for both). When compared with ≥50% stenosis by CTA, the specificity for detecting ischemia by SFR increased from 43% to 91%, while the sensitivity decreased from 95% to 62%. Accordingly, the positive and negative predictive values were 85% and 73%, respectively. The combination of stenosis ≥50% by CTA and SFR resulted in an area under the curve of 0.91, which was significantly higher compared with hyperemic MBF (area under the curve = 0.79; p = 0.013).
Conclusions:
Calculation of SFR by dynamic CTP provides a novel and accurate method to identify flow-limiting coronary stenosis.
More Related Videos
Related Concept Videos
01:30Acute Coronary Syndrome III: Diagnostic Studies
01:28Imaging Studies for Cardiovascular System V: CT
01:25Imaging Studies for Cardiovascular System VI: Calcium -Scoring CT