Coronary angiography-derived index for assessing microcirculatory resistance in patients with non-obstructed vessels: The FLASH index of microcirculatory resistance (IMR) study
Authors' conclusion
Angiography-based caIMR has a good diagnostic yield with wire-based IMR.
Study context
- Population
- Patients with suspected myocardial ischaemia with nonobstructive coronary arteries
- Participants
- 113 paired measurements
- Comparison
- caIMR vs wire-based IMR
- Outcome
- Diagnostic accuracy of caIMR vs wire-based IMR (performance goal 82%)
Methodological detailsprospective, multicentre, randomised order of tests, blinded core laboratory
- Prospective
- Multicentre
- Randomised order of tests
- Blinded core laboratory
Performance
As reported in the abstract
Diagnostic performance of caIMR
| Test or model | Diagnostic accuracy | Sensitivity | Specificity | PPV | NPV | AUC |
|---|---|---|---|---|---|---|
| caIMR | 93.8% (95% CI: 87.7%-97.5%) | 95.1% (95% CI: 83.5%- 99.4%) | 93.1% (95% CI: 84.5%-97.7%) | 88.6% (95% CI: 75.4%-96.2%) | 97.1% (95% CI: 89.9%-99.7%) | 0.963 (95% CI: 0.928-0.999) |
caIMR
Diagnostic accuracy93.8% (95% CI: 87.7%-97.5%)
Sensitivity95.1% (95% CI: 83.5%- 99.4%)
Specificity93.1% (95% CI: 84.5%-97.7%)
PPV88.6% (95% CI: 75.4%-96.2%)
NPV97.1% (95% CI: 89.9%-99.7%)
AUC0.963 (95% CI: 0.928-0.999)
Original publication
Coronary angiography-derived index for assessing microcirculatory resistance in patients with non-obstructed vessels: The FLASH IMR study. Am Heart J. Published 12 April 2023. doi:10.
Summarised from the published abstract; every number is checked against it