Work

Vessel-specific angiography-derived index of microcirculatory resistance in an all-comer population undergoing percutaneous coronary intervention, a PIONEER IV trial substudy

Year: 2025

Type: article

Abstract: BACKGROUND: Recently, angiography-derived index of microvascular resistance (angio-IMR) has emerged as a less invasive alternative to estimate CMD during cardiac catheterization. Whether CMD differs across vessel territories and populations remains disputed. METHODS: Consecutive all-comer patients undergoing coronary angiography for chronic coronary syndrome (CCS) or non-ST-elevation myocardial infarction (NSTEMI) enrolled in the PIONEER-IV trial at the University Medical Center Groningen were included. Angio-IMR was retrospectively calculated using quantitative flow ratio (QFR) software in all three major coronary vessel territories pre- and post-PCI, if applicable. Angio-IMR levels were compared between coronary vessels, indication, and sex. The association between angio-IMR and LV function on AI-derived echocardiography analyses were assessed. RESULTS: In 220 patients, mean age was 65 ± 9 years, 18.3 % were women, and 20.3 % presented with NSTEMI. CMD was common: 80.0 % had baseline angio-IMR ≥25 mmHg·s/cm. Angio-IMR was similar in the LAD, RCA and LCX in both target and non-target vessels (p > 0.05). In the LAD, angio-IMR increased significantly post-PCI (p < 0.001), while RCA and LCX showed no significant change. Whilst NSTEMI patients showed similar baseline angio-IMR as CCS patients, they had lower post-PCI angio-IMR (p = 0.011). Women had lower average post-PCI angio-IMR (27 vs. 37 mmHg·s/cm, p < 0.001) and showed improved microvascular resistance post-PCI. Angio-IMR was not associated with cardiac function overall, but in NSTEMI patients, higher baseline angio-IMR correlated with worse LV function. CONCLUSION: Angio-IMR is similar in all coronary vessels, but lower in NSTEMI patients than in CCS and lower in women. In NSTEMI patients, higher IMR was associated with worse LV function.

Source: Cardiovascular revascularization medicine

DOI: 10.1016/j.carrev.2025.12.017