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Interventional Diagnostic Procedure: A Practical Guide for the Assessment of Coronary Vascular Function
Published on: March 15, 2022
Prognostic Value of Coronary Microvascular Function Measured Immediately After Percutaneous Coronary Intervention in
Takeshi Nishi1, Tadashi Murai2, Giovanni Ciccarelli3
1Division of Cardiovascular Medicine, Stanford University School of Medicine and Stanford Cardiovascular Institute, CA (T.N., S.V.S., Y.K., F.D., W.F.F.).
Insights
High index of microcirculatory resistance (IMR) after percutaneous coronary intervention (PCI) indicates worse outcomes. This finding highlights the prognostic value of assessing microvascular function post-PCI in stable coronary artery disease patients.
Area of Science:
- Cardiology
- Vascular Biology
- Interventional Cardiology
Background:
- Coronary microvascular dysfunction (CMD) prognostic impact post-PCI in stable coronary artery disease (CAD) is not fully understood.
- Assessing microvascular function immediately after PCI is crucial for risk stratification.
Purpose of the Study:
- To investigate the prognostic value of microvascular function, measured by the index of microcirculatory resistance (IMR), immediately after percutaneous coronary intervention (PCI).
- To determine if high IMR post-PCI predicts major adverse cardiac events (MACE) in patients with stable CAD.
Main Methods:
- A total of 572 stable CAD patients undergoing PCI were enrolled across 8 centers in 4 countries.
- Index of microcirculatory resistance (IMR) was measured immediately post-PCI; impaired function defined as IMR ≥25 (high IMR).
- Major adverse cardiac events (MACE), including death, myocardial infarction (MI), and target vessel revascularization, were tracked over a median follow-up of 4.0 years.
Main Results:
- Patients with high IMR had significantly higher cumulative MACE rates (HR, 1.56; P=0.001), driven by periprocedural MI (HR, 1.59; P=0.004).
- Trends suggested higher risks for mortality, spontaneous MI, and target vessel revascularization in the high IMR group.
- Multivariable analysis confirmed high post-PCI IMR as an independent predictor of MACE.
Conclusions:
- Index of microcirculatory resistance (IMR) measured immediately after PCI is a significant predictor of adverse events in stable coronary artery disease patients.
- Microvascular function assessment post-PCI provides valuable prognostic information for risk stratification and management.
Background:
The prognostic impact of coronary microvascular dysfunction after percutaneous coronary intervention (PCI) remains unclear in patients with stable coronary artery disease. This study sought to investigate the prognostic value of microvascular function measured immediately after PCI in patients with stable coronary artery disease.
Methods:
We enrolled 572 patients with stable coronary artery disease who underwent PCI and elective measurement of the index of microcirculatory resistance (IMR) immediately after PCI from 8 centers in 4 countries. Impaired microvascular function was defined as IMR≥25 (high IMR). Major adverse cardiac events, including death, myocardial infarction (MI) and target vessel revascularization, were evaluated.
Results:
During a median follow-up duration of 4.0 years, the cumulative major adverse cardiac events rate was significantly higher in the high IMR group (n=66/148) compared with the low IMR group (n=128/424; hazard ratio [HR], 1.56; 95% CI, 1.16-2.105; P=0.001), primarily due to a higher rate of periprocedural MI (HR, 1.59; 95% CI, 1.11-2.28; P=0.004) but also due to higher rates of mortality (HR, 1.59; 95% CI, 0.76-3.35; P=0.22), spontaneous MI (HR, 2.10; 95% CI, 0.67-6.63; P=0.20) and target vessel revascularization (HR, 1.40; 95% CI, 0.77-2.54; P=0.27). Cumulative risk for death, spontaneous MI, and target vessel revascularization was higher in the high IMR group (HR, 1.55; 95% CI, 0.99-2.43; P=0.056), as was death and spontaneous MI alone (HR, 1.79; 95% CI, 0.96-3.36; P=0.065). On multivariable analysis, high IMR post-PCI was an independent predictor of major adverse cardiac events.
Conclusions:
IMR measured immediately after PCI predicts adverse events in patients with stable coronary artery disease.
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