Predictive value of pre-procedural computed tomography-derived extracellular volume fraction for post-PCI coronary microcirculation in chronic coronary syndrome
K Sayama, Y Kanaji, E Usui, H Ueno, T Watanabe, T Watanabe, R Murakami, S Hiroi, K Hosokawa, T KakutaAbstract
Background
Myocardial extracellular volume fraction (ECV) derived from coronary computed tomography angiography (CCTA) is an established surrogate for myocardial interstitial characterization, including fibrosis, inflammation, and edema. While post-percutaneous coronary intervention (PCI) coronary flow velocity reserve (CFVR)—measured via stress transthoracic Doppler echocardiography (S-TDE)—is a pivotal prognostic indicator of microvascular integrity in chronic coronary syndrome (CCS), the mechanistic link between pre-procedural structural remodeling (ECV) and post-procedural functional outcomes (CFVR) remains to be elucidated.
Methods
We prospectively evaluated CCS patients undergoing CCTA prior to PCI for de novo left anterior descending artery (LAD) lesions, followed by post-PCI S-TDE. The primary objective was to determine the association between pre-PCI ECV within the LAD territory (LAD-ECV) and post-PCI microvascular dysfunction, defined as a CFVR <2.5.
Results
Of the 43 patients enrolled (mean age 67.6±11.3 years), 52.8% exhibited impaired post-PCI CFVR. Pre-PCI LAD-ECV demonstrated a robust inverse correlation with post-PCI CFVR (R = -0.460, P = 0.002). Multivariable linear regression identified LAD-ECV (β = -0.079, P < 0.001) and estimated glomerular filtration rate (β = 0.014, P = 0.009) as independent predictors of post-PCI CFVR. Notably, LAD-ECV was the sole significant predictor for impaired CFVR in logistic regression analysis (OR: 1.33, P = 0.002). Receiver operating characteristic analysis revealed a superior diagnostic performance for LAD-ECV (AUC 0.854), with an optimal threshold of 31.8%. Patients with LAD-ECV >31.8% had a strikingly higher prevalence of microvascular impairment compared to those below the threshold (80.8% vs. 6.2%, P < 0.001).
Conclusion
Pre-procedural CCTA-derived ECV serves as a novel and potent predictor of post-PCI microvascular function. This non-invasive structural assessment offers critical insights into the functional recovery of the coronary microvasculature following revascularization in patients with CCS.