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Interventional Diagnostic Procedure: A Practical Guide for the Assessment of Coronary Vascular Function
Published on: March 15, 2022
Percutaneous coronary intervention increases microvascular resistance in patients with non-ST-elevation acute
Cansu Akdeniz1, Sabahattin Umman, Yilmaz Nisanci
1Department of Cardiology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey.
Insights
Percutaneous coronary intervention (PCI) for non-ST-elevation myocardial infarction (NSTEMI) increases microvascular resistance (MR) when accounting for collateral flow. This effect was more pronounced in patients who experienced periprocedural myocardial infarction.
Area of Science:
- Cardiology
- Interventional Cardiology
- Vascular Physiology
Background:
- The interplay between epicardial coronary artery stenosis and microcirculation in acute coronary syndromes remains unclear.
- Understanding microvascular resistance (MR) post-intervention is crucial for non-ST-elevation myocardial infarction (NSTEMI) management.
Purpose of the Study:
- To evaluate the immediate effect of percutaneous coronary intervention (PCI) on microvascular resistance (MR).
- To assess changes in MR in patients with NSTEMI following stenting of the culprit lesion.
Main Methods:
- Thirty-eight NSTEMI patients undergoing PCI were studied.
- Microvascular resistance (MR) was calculated using coronary wedge pressure and distal pressure/velocity measurements before and after stenting.
- Collateral flow was incorporated into MR calculations.
Main Results:
- Overall MR increased significantly post-PCI when collateral flow was considered (1.70 to 2.05, p=0.001).
- Changes in MR correlated significantly with changes in troponin T (r=0.629, p=0.0001).
- Patients with periprocedural myocardial infarction showed a significant MR increase post-PCI (1.48 to 2.28, p<0.001), unlike those without.
Conclusions:
- Epicardial stenosis removal via PCI increases MR in NSTEMI patients, particularly when collateral flow is factored in.
- The findings highlight the impact of epicardial intervention on coronary microvascular function in NSTEMI.
Aims:
In the acute coronary syndrome setting, the interaction between epicardial coronary artery stenosis and microcirculation subtended by the culprit vessel is poorly understood. The purpose of the present study was to assess the immediate impact of percutaneous coronary intervention (PCI) on microvascular resistance (MR) in patients with non-ST-elevation myocardial infarction (NSTEMI).
Methods And Results:
Thirty-eight patients undergoing PCI for NSTEMI were recruited consecutively. Culprit lesions were stented over a Doppler and pressure-sensor-equipped guidewire. In the presence of epicardial stenosis, MR was calculated by taking collateral flow, as measured by the coronary wedge pressure, into consideration. After removal of epicardial stenosis, MR was calculated simply as distal coronary pressure divided by average peak velocity. When collateral flow was incorporated into the calculation, MR increased significantly from 1.70 ± 0.76 to 2.05 ± 0.72 (p=0.001) after PCI in the whole population. Periprocedural changes (Δ) in absolute values of MR and troponin T correlated significantly (r=0.629, p=0.0001). In patients who developed periprocedural myocardial infarction, MR increased significantly after PCI (1.48 ± 0.73 versus 2.28 ± 0.71, p<0.001). Nevertheless, removal of the epicardial lesion did not change MR in patients without periprocedural MI (1.91±0.73 versus 1.81±0.67, p=0.1).
Conclusions:
When collateral flow is accounted for, removal of epicardial stenosis increases MR in patients with NSTEMI undergoing PCI.
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