{
  "abstract": "Introduction: Peripheral microvascular endothelial function measured by the reactive hyperemia index (RHI) with EndoPAT predicts cardiovascular outcomes, and post-procedural RHI has been associated with binary in-stent restenosis. Whether pre-procedural RHI relates to in-stent late lumen loss (LLL) measured by quantitative coronary angiography (QCA) after percutaneous coronary intervention (PCI), and whether any association depends on device caliber, has not been established.\n\nMethods: We retrospectively analyzed 132 patients who underwent EndoPAT before PCI (index PCI 2009-2016). The primary endpoint was in-stent LLL at follow-up angiography ( n = 91; median follow-up 9.4 months). Because in-stent LLL was highly skewed, the primary analysis used Spearman correlation and a robust (HC3) multivariable regression adjusting for age, diabetes, hypertension, number of diseased vessels, and pre-PCI minimal lumen diameter. Pre-specified sensitivity analyses included multiple imputation (MICE, m = 20) for missing follow-up and lesion-level generalized estimating equations (GEE). Subgroup analyses by implanted stent diameter (≤2.75 versus >2.75 mm) and diabetes were exploratory.\n\nResults: RHI showed only a borderline inverse correlation with in-stent LLL ( ρ = −0.19, p = 0.07) and was not independently associated with it (adjusted β = −0.11, 95% CI −0.39 to +0.18, p = 0.45); multiple imputation ( β = −0.08) and GEE ( β = −0.07) were concordant, and no correlation survived false-discovery-rate correction. Stratification by native reference vessel diameter showed no association, whereas stratification by implanted stent diameter revealed an inverse RHI–LLL correlation confined to small-diameter stents (≤2.75 mm, n = 33; ρ = −0.375, p = 0.032) but not larger stents ( ρ = −0.055). However, the stent-diameter × RHI interaction was not significant ( p = 0.48), so this caliber-dependent signal is hypothesis-generating and tracks the achieved implanted caliber rather than the native reference vessel. Inflammation explained neither result. High-sensitivity C-reactive protein (hs-CRP) was unrelated to RHI ( ρ = −0.02) and to in-stent LLL ( ρ = +0.15), and adding it to the primary model left the RHI estimate unchanged. Small-caliber recipients had similar hs-CRP but more diabetes (57.6% versus 27.6%, p = 0.009) and worse renal function ( p = 0.008), indicating a higher-risk phenotype rather than a pure caliber stratum.\n\nDiscussion: Pre-procedural EndoPAT RHI was not independently associated with in-stent LLL. The exploratory signal confined to small-caliber stents is hypothesis-generating and requires prospective, device-caliber-stratified validation pairing pre- with post-procedural RHI.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Internal Medicine, Seoul National University Hospital, Seoul National University College of Medicine",
    "Cardiovascular Center, Seoul National University Boramae Medical Center"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 6,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Hangyeol Kim"
    },
    {
      "affs": [
        1
      ],
      "name": "Hyun Sung Joh"
    },
    {
      "affs": [
        1
      ],
      "name": "Woo-Hyun Lim"
    },
    {
      "affs": [
        1
      ],
      "name": "Hack-Lyoung Kim"
    },
    {
      "affs": [
        1
      ],
      "name": "Sang-Hyun Kim"
    },
    {
      "affs": [
        1
      ],
      "name": "Jae-Bin Seo"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/c71re1szwc51j.bib",
  "cited_by": 0,
  "doi": "10.3389/fcvm.2026.1940897",
  "fulltext_url": null,
  "id": "c71re1szwc51j",
  "issns": [
    "2297-055X"
  ],
  "landing_url": "https://www.frontiersin.org/articles/10.3389/fcvm.2026.1940897/full",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2746|Coronary Interventions and Diagnostics"
    ]
  ],
  "openalex": "W7223999817",
  "pdf_url": "https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2026.1940897/pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-27",
  "publisher": "Frontiers Media SA",
  "ris": "https://research.draconitic.com/paper/c71re1szwc51j.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:20:10Z",
      "native_id": "10.3389/fcvm.2026.1940897",
      "source": "crossref",
      "url": "https://www.frontiersin.org/articles/10.3389/fcvm.2026.1940897/full"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2746|Coronary Interventions and Diagnostics",
      "subfield": "surgery"
    }
  ],
  "title": "Peripheral microvascular function and in-stent late lumen loss after percutaneous coronary intervention: a retrospective cohort study with an exploratory analysis by implanted stent diameter",
  "title_text": "Peripheral microvascular function and in-stent late lumen loss after percutaneous coronary intervention: a retrospective cohort study with an exploratory analysis by implanted stent diameter",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:20:10Z",
  "url": "https://research.draconitic.com/paper/c71re1szwc51j",
  "venue": "Frontiers in Cardiovascular Medicine",
  "versions": []
}