Precision and reproducibility of quantitative coronary angiography with applications to controlled clinical trials. A...

Area of Science:

• Cardiovascular imaging
• Medical image analysis
• Quantitative angiography

Background:

• Current computer methods for coronary artery disease (CAD) quantification primarily analyze angiographic frames from end-diastole.
• The optimal cardiac cycle phase for sampling angiographic data to assess CAD remains debated.

Purpose of the Study:

• To evaluate if end-diastole is the optimal sampling phase for coronary angiograms.
• To compare the precision and reproducibility of different cardiac cycle sampling schemes for CAD quantification.

Main Methods:

• Analysis of 20 cinecoronary angiograms from a plasma lipid-lowering trial.
• Implementation of various sampling schemes: sequential and random sampling of 2-5 frames across the cardiac cycle, systole, and diastole.
• Evaluation of three vessel measures and percent stenosis for each sampling scheme.

Main Results:

• Sequential end-diastolic sampling yielded the most precise estimates of vessel measures (minimum intra-cycle variability).
• Random sampling within the cardiac cycle demonstrated the best reproducibility (consistent values across cycles).
• Average vessel segment diameter was the most precise and reproducible measure evaluated.

Conclusions:

• Optimal cardiac cycle sampling for coronary angiography depends on whether precision or reproducibility is prioritized.
• Sequential end-diastole is best for precision, while random cycle sampling is superior for reproducibility in CAD assessment.
• Average vessel diameter is a robust measure for CAD quantification due to its high precision and reproducibility.