Coronary physiology thresholds associated with microvascular obstruction in myocardial infarction
Authors' conclusion
IMR and CFR are associated with the presence of microvascular obstruction in STEMI. Patients with an IMR>31 units and a CFR≤1.25 have higher prevalence of microvascular obstruction, lower left ventricular ejection fraction, larger infarct size and area at risk.
Study context
- Population
- Patients with STEMI after primary PCI, 5 tertiary centres in Italy, November 2020–December 2021
- Participants
- 102 consecutive patients
- Exposure
- Index of microvascular resistance (IMR) and coronary flow reserve (CFR) strata
- Outcome
- Microvascular obstruction by CMR, predicted by IMR and CFR measured in the culprit vessel soon after primary PCI
Methodological detailsmulticentre, consecutive patients
- Multicentre
- Consecutive patients
Main finding
As reported in the abstract
Microvascular obstruction prevalence
P < 0.001
Observational data: associations, not effects.
Further findings
LVEF — IMR>31 and CFR≤1.25 vs IMR≤31 and CFR>1.25
P = 0.043
| Outcome | P value |
|---|---|
| LVEFIMR>31 and CFR≤1.25 vs CFR≤1.25 and IMR≤31 | P = 0.025 |
Infarct size and area at risk
- Larger with IMR>31 and CFR≤1.25 than in other groups
Original publication
Coronary physiology thresholds associated with microvascular obstruction in myocardial infarction. Heart. Published 25 October 2023. doi:10.
Summarised from the published abstract; every number is checked against it