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Changes in microvascular resistance following percutaneous coronary intervention - From the ILIAS global registry
Ashkan Eftekhari1, Tim P van de Hoef2, Masahiro Hoshino3
1Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark; Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark.
Insights
Increased microvascular resistance post-percutaneous coronary intervention is linked to higher rates of target vessel failure. This finding highlights the prognostic significance of microvascular resistance changes after PCI.
Area of Science:
- Cardiology
- Interventional Cardiology
- Vascular Physiology
Background:
- Microvascular resistance (MR) is a prognostic indicator in acute and chronic coronary syndromes post-percutaneous coronary intervention (PCI).
- Previous research has not fully explored the determinants of MR changes and their association with target vessel failure (TVF).
Purpose of the Study:
- To investigate the association between changes in microvascular resistance (MR) after PCI and the occurrence of target vessel failure (TVF).
Main Methods:
- Analysis of paired pre- and post-PCI hemodynamic data from the ILIAS registry.
- Categorization of vessels based on the percentage change in MR post-PCI (decrease/no change vs. increase).
- Cox regression analysis to determine the association between MR changes and TVF.
Main Results:
- A decrease in MR (ΔMR % ≤ 0) was associated with lower baseline fractional flow reserve and coronary flow reserve, and higher hyperemic and index of microvascular resistance.
- No significant differences in angiographic parameters were observed between groups with increased or decreased MR.
- An increase in MR post-PCI (ΔMR % > 0) was significantly associated with an increased rate of TVF (HR 3.6 [1.2; 10.3], p=0.018).
Conclusions:
- Increased microvascular resistance after PCI is linked to baseline hemodynamic characteristics of less severe lesions.
- Elevated MR post-PCI is an independent predictor of higher rates of target vessel failure.
Background:
Microvascular resistance (MR) has prognostic value in acute and chronic coronary syndromes following percutaneous coronary intervention (PCI), however anatomic and physiologic determinants of the relative changes of MR and its association to target vessel failure (TVF) has not been investigated previously. This study aims to evaluate the association between changes in MR and TVF.
Methods:
This is a sub-study of the Inclusive Invasive Physiological Assessment in Angina Syndromes (ILIAS) registry which is a global multi-centre initiative pooling lesion-level coronary pressure and flow data.
Results:
Paired pre-post PCI haemodynamic data were available in n = 295 vessels out of n = 828 PCI treated patients and of these paired data on MR was present in n = 155 vessels. Vessels were divided according to increase vs. decrease % in microvascular resistance following PCI (ΔMR % ≤ 0 vs. ΔMR > 0%). Decreased microvascular resistance ΔMR % ≤ 0 occurred in vessels with lower pre-PCI fractional flow reserve (0.67 ± 0.15 vs. 0.72 ± 0.09 p = 0.051), coronary flow reserve (1.9 ± 0.8 vs. 2.6 ± 1.8 p < 0.0001) and higher hyperemic microvascular resistance (2.76 ± 1.3 vs. 1.62 ± 0.74 p = 0.001) and index of microvascular resistance (24.4 IQ (13.8) vs. 15. 8 IQ (13.2) p = 0.004). There was no difference in angiographic parameters between ΔMR % ≤ 0 vs. ΔMR > 0%. In a cox regression model ΔMR % > 0 was associated with increased rate of TVF (hazard ratio 95% CI 3.6 [1.2; 10.3] p = 0.018).
Conclusion:
Increased MR post-PCI was associated with lesions of less severe hemodynamic influence at baseline and higher rates of TVF at follow-up.
