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Coronary Microvascular Function Assessment using the Coronary Angiography-Derived Index of Microcirculatory
Ming Li1, Xi Peng1, Naixin Zheng1
1Department of Cardiology, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, 100730 Beijing, China.
Insights
Coronary microvascular dysfunction is common in ST-segment elevation myocardial infarction (STEMI) patients after primary percutaneous coronary intervention (PCI). An elevated coronary angiography-derived index of microcirculatory resistance (caIMR) predicts major adverse cardiovascular events.
Area of Science:
- Cardiology
- Interventional Cardiology
- Vascular Biology
Background:
- Coronary microvascular function assessment post-primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) is limited.
- Coronary angiography-derived index of microcirculatory resistance (caIMR) offers a method to evaluate microvascular function in the infarct-related artery (IRA).
Purpose of the Study:
- To assess coronary microvascular function using caIMR in STEMI patients undergoing primary PCI.
- To determine the association between caIMR and major adverse cardiovascular events (MACE) post-primary PCI.
Main Methods:
- The FlashAngio system was used to measure caIMR in 157 STEMI patients post-primary PCI.
- MACE was defined as a composite of cardiac mortality, target vessel revascularization, and rehospitalization for heart failure, myocardial infarction, or angina.
Main Results:
- Approximately 30% of STEMI patients with successful primary PCI had an IRA caIMR < 40.
- IRA caIMR was significantly higher than reference vessel caIMR (p < 0.001).
- An IRA caIMR ≥ 40 was associated with higher 3-month and 1-year MACE rates, primarily driven by rehospitalizations for heart failure, myocardial infarction, or angina.
Conclusions:
- STEMI patients frequently exhibit coronary microvascular dysfunction after primary PCI, indicated by elevated IRA caIMR.
- An IRA caIMR ≥ 40 independently predicts MACE at 3 months and 1 year in STEMI patients post-primary PCI.
Background:
Studies reporting the status of coronary microvascular function in the infarct-related artery (IRA) after primary percutaneous coronary intervention (PCI) remain limited. This study utilized the coronary angiography-derived index of microcirculatory resistance (caIMR) to assess coronary microvascular function in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary PCI.
Methods:
We used the FlashAngio system to measure the caIMR after primary PCI in 157 patients with STEMI. The primary endpoint was the occurrence of a major adverse cardiovascular event (MACE), defined as a composite endpoint encompassing cardiac mortality, target vessel revascularization, and rehospitalization due to congestive heart failure (CHF), myocardial infarction (MI), or angina.
Results:
Approximately 30% of patients diagnosed with STEMI and who experienced successful primary PCI during the study period had a caIMR in the IRA of 40. The caIMR in the IRA was significantly higher than in the reference vessel (32.9 15.8 vs. 27.4 11.1, p 0.001). The caIMR in the reference vessel of the caIMR 40 group was greater than in the caIMR 40 group (30.9 11.3 vs. 25.9 10.7, p = 0.009). Moreover, the caIMR 40 group had higher incidence rates of MACEs at 3 months (25.5% vs. 8.3%, p = 0.009) and 1 year (29.8% vs. 13.9%, p = 0.04), than in the caIMR 40 group, which were mainly driven by a higher rate of rehospitalization due to CHF, MI, or angina. A caIMR in the IRA of 40 was an independent predictor of a MACE at 3 months (hazard ratio (HR): 3.459, 95% confidence interval (CI): 1.363-8.779, p = 0.009) and 1 year (HR: 2.384, 95% CI: 1.100-5.166, p = 0.03) in patients with STEMI after primary PCI.
Conclusions:
Patients with STEMI after primary PCI often have coronary microvascular dysfunction, which is indicated by an increased caIMR in the IRA. An elevated caIMR of 40 in the IRA was associated with an increased risk of adverse outcomes in STEMI patients undergoing primary PCI.
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