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Association of quantitative flow ratio with in-stent restenosis in patients with unstable angina undergoing
Dongchao Liu1, Zheng Xue, Jingxian Qi
1Department of Cardiology, Shijiazhuang People's Hospital, Shijiazhuang, Hebei Province, China.
Insights
A poor quantitative flow ratio (QFR) below 0.91 after percutaneous coronary intervention (PCI) significantly increases the risk of in-stent restenosis (ISR) in unstable angina patients. This finding highlights QFR as a crucial predictor for adverse outcomes post-PCI.
Area of Science:
- Cardiovascular Medicine
- Interventional Cardiology
- Biomedical Engineering
Background:
- In-stent restenosis (ISR) remains a significant complication following percutaneous coronary intervention (PCI).
- Quantitative flow ratio (QFR) is an emerging physiological index assessing blood flow post-PCI.
- Predictive markers for ISR are crucial for optimizing patient management.
Purpose of the Study:
- To evaluate the association between post-PCI quantitative flow ratio (QFR) and the incidence of in-stent restenosis (ISR).
- To identify QFR thresholds predictive of ISR in patients with unstable angina.
Main Methods:
- Patients undergoing PCI for unstable angina were categorized into poor (QFR < 0.91) and good (QFR ≥ 0.91) QFR groups.
- Clinical data and ISR rates at 10-month follow-up were analyzed.
- Statistical analysis, including risk factor adjustment, was performed.
Main Results:
- The incidence of ISR was significantly higher in the poor QFR group (33.9%) compared to the good QFR group (6.9%).
- A QFR < 0.91 was identified as a significant independent risk factor for ISR.
- Diabetes was also confirmed as an independent risk factor for ISR.
Conclusions:
- Post-PCI QFR < 0.91 is a strong independent predictor of ISR in unstable angina patients.
- A lower QFR is linearly associated with an increased risk of ISR.
- QFR assessment can aid in stratifying risk and guiding further management post-PCI.
Objective:
To investigate the association of post-percutaneous coronary intervention (PCI) quantitative flow ratio (QFR) with in-stent restenosis (ISR) in patients with unstable angina.
Materials And Methods:
Patients treated with PCI and follow-up for ISR were divided into a poor QFR group (QFR < 0.91) and a good QFR group with (QFR ≥ 0.91). All clinical data were analyzed.
Results:
Among 143 patients enrolled, 57 (39.9%) patients were in the poor QFR group and 86 (60.1%) in the good QFR group. After stenting, the stenosis was decreased to 0 from ≥80% before PCI. At 10-month follow-up, the incidence of ISR in the good QFR group was 6.9%, significantly lower than 33.9% in the poor QFR group (P < 0.05). QFR < 0.91 was a significant (P = 0.002) risk factor for ISR, 4.25 times that of patients with QFR ≥ 0.91. After adjusting for age and sex, the risk of developing ISR in patients with poor QFR was 4.51 times that in patients with good QFR [95% confidence interval (CI): 1.76-11.54, P = 0.002], and QFR < 0.91 (adjusted risk ratio: 6.57, 95% CI: 2.45-17.60, P < 0.001) and diabetes (adjusted risk ratio: 7.23, 95% CI: 2.81-18.60, P < 0.001) were two independent risk factors for ISR.
Conclusion:
A positive linear relationship exists between QFR and ISR after adjusting for age and sex, and poor QFR < 0.91 after PCI is a significant independent risk factor for ISR among unstable angina patients undergoing PCI.
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