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Updated: Jun 18, 2026
Evaluation of Coronary Flow Reserve After Myocardial Ischemia Reperfusion in Rats
Published on: June 28, 2019
A new angiographic method to assess coronary flow reserve-validation in humans
Harald Rittger1, Asher Kuper, Ole-Alexander Breithardt
1Medizinische Klinik II, Klinikum Coburg gGmbH, Coburg, Germany. rittger@arcor.de
Insights
A new method estimates coronary flow reserve (CFR) using coronary angiograms, avoiding invasive procedures. This angiogram-based CFR measurement correlates well with Doppler-derived CFR, offering a comparable alternative for assessing coronary circulation.
Area of Science:
- Cardiology
- Medical Imaging
- Hemodynamics
Background:
- Coronary flow reserve (CFR) assesses coronary circulation integrity.
- Traditional CFR measurement requires invasive intracoronary procedures.
- A novel algorithm estimates CFR from coronary angiograms non-invasively.
Purpose of the Study:
- To evaluate a new algorithm for estimating CFR from coronary angiograms.
- To compare non-invasive CFR measurements with invasive Doppler-derived CFR.
- To determine the feasibility and accuracy of angiogram-based CFR.
Main Methods:
- Twenty-seven patients with chest pain underwent cardiac catheterization.
- Coronary flow reserve was measured using Doppler wire (CFR(doppler)).
- Coronary angiograms were analyzed using densitometry to calculate CFR(angio).
Main Results:
- An excellent correlation was observed between CFR(angio) and CFR(doppler) (r=0.87, P<0.0001).
- The average absolute difference between both methods was 0.36 +/- 0.31.
- CFR(angio) demonstrated high agreement with CFR(doppler).
Conclusions:
- Angiogram-based CFR measurement is feasible.
- This non-invasive method provides results comparable to Doppler-derived CFR.
- Coronary angiography densitometry offers a viable alternative for CFR assessment.
Background:
Coronary flow reserve (CFR) is defined as the ratio between coronary artery flow during maximal hyperemia and rest. It is considered as a marker for the integrity of the epicardial coronary circulation and the microcirculation. CFR measurement typically requires the introduction of a guide wire into a diseased coronary artery. We tested a new algorithm, which allows to estimate CFR by analysis of coronary angiograms without the need for direct intracoronary measurements.
Methods:
Twenty seven patients (10 female, mean age 64 +/- 11 years) underwent diagnostic cardiac catheterization for the evaluation of chest pain. A Doppler wire was introduced into the diseased coronary artery and CFR(doppler) was calculated by the flow velocity ratio between rest and maximal hyperemia, induced by intravenous administration of 140 microg of adenosine per kg bodyweight. This was compared to the angiographically determined CFR (CFR(angio)) under the same conditions (rest and induced maximal hyperemia) by densitometry. CFR(angio) was based on the creation of two time density curves representing the disappearance of contrast over time. CFR(angio) was the resulting ratio between the density values during hyperemia and rest.
Results:
An excellent correlation was found between CFR(doppler) and CFR(angio): CFR(angio) = 1 x CFR(doppler) (r = 0.87; P < 0.0001). The average absolute difference between both indeces was 0.36 +/- 0.31.
Conclusion:
Measurement of CFR(angio) by densitometry is feasible and provides results, which are comparable to Doppler-derived intracoronary flow velocity measurements.
