{
  "abstract": "Background Coronary microvascular dysfunction (CMD) is common among patients with angina with non-obstructive coronary artery disease (ANOCA) and leads to poorer clinical outcomes. Exercise stress testing (EST) was shown to have a high specificity for detecting CMD. However, the relationship between diagnosing CMD using different invasive physiological parameters and thresholds and the association between EST findings and the endotype of CMD remains unknown.Methods This multicentre, prospective cohort study enrolled 117 patients with ANOCA who underwent EST prior to invasive coronary angiography with functional assessment to measure coronary flow reserve (CFR), the index of microvascular resistance (IMR) and microvascular resistance reserve (MRR)=(CFR/FFR)×(P a rest/Pa hyper). CMD was classified using multiple criteria, including MRR <3.0, CFR <2.5 and CFR <2.0 or IMR ≥25. Diagnostic sensitivity and specificity and the accuracy of EST findings (exercise-induced chest discomfort, ischaemic ECG changes and exercise intolerance) for diagnosing CMD were assessed.Results The prevalence of CMD was similar under all three definitions. However, structural CMD was more common using MRR <3.0. Ischaemic ECG changes during EST showed an excellent diagnostic accuracy of 86.3% (78.7–92.0%) for detecting CMD, with a sensitivity and specificity of 86.2% (68.3–96.1%) and 86.4% (77.4–92.8%), respectively. Exercise-induced chest discomfort also had a good diagnostic accuracy of 76.1% (95% CI 67.3% to 83.5%); however, it offered no additional value when added to ischaemic ECG changes. EST preferentially identified structural CMD, while functional CMD was more frequently missed.Conclusions Ischaemic ECG changes during EST performed immediately before invasive functional assessment demonstrated excellent diagnostic accuracy for identifying patients with CMD, particularly the structural endotype.Trial registration number NCT05841485.",
  "authors": [
    {
      "affiliations": [
        "CORRIB Research Centre for Advanced Imaging and Core Lab, University of Galway, Galway, Ireland",
        "Cardiovascular Center, Taichung Veterans General Hospital, Taichung, Taiwan"
      ],
      "name": "Tsung-Ying Tsai"
    },
    {
      "affiliations": [
        "CORRIB Research Centre for Advanced Imaging and Core Lab, University of Galway, Galway, Ireland",
        "Bon Secours Hospital Limerick, Limerick, Ireland",
        "Lithuanian University of Health Sciences, Kaunas, Lithuania"
      ],
      "name": "Ali Aldujeli"
    },
    {
      "affiliations": [
        "Houston Methodist Hospital, Houston, Texas, USA"
      ],
      "name": "Ayman Haq"
    },
    {
      "affiliations": [
        "CORRIB Research Centre for Advanced Imaging and Core Lab, University of Galway, Galway, Ireland"
      ],
      "name": "Paddy Murphy"
    },
    {
      "affiliations": [
        "Lithuanian University of Health Sciences, Kaunas, Lithuania"
      ],
      "name": "Ramunas Unikas"
    },
    {
      "affiliations": [
        "Lithuanian University of Health Sciences, Kaunas, Lithuania"
      ],
      "name": "Diana Žaliaduonytė-Pekšienė"
    },
    {
      "affiliations": [
        "Lithuanian University of Health Sciences, Kaunas, Lithuania"
      ],
      "name": "Rima Braukyliene"
    },
    {
      "affiliations": [
        "Department of Cardiology, University Hospital Limerick, Dooradoyle, Ireland"
      ],
      "name": "Thomas John Kiernan"
    },
    {
      "affiliations": [
        "CORRIB Research Centre for Advanced Imaging and Core Lab, University of Galway, Galway, Ireland"
      ],
      "name": "Pruthvi C Revaiah"
    },
    {
      "affiliations": [
        "CORRIB Research Centre for Advanced Imaging and Core Lab, University of Galway, Galway, Ireland"
      ],
      "name": "Kotaro Miyashita"
    },
    {
      "affiliations": [
        "CORRIB Research Centre for Advanced Imaging and Core Lab, University of Galway, Galway, Ireland"
      ],
      "name": "Akihiro Tobe"
    },
    {
      "affiliations": [
        "CORRIB Research Centre for Advanced Imaging and Core Lab, University of Galway, Galway, Ireland"
      ],
      "name": "Asahi Oshima"
    },
    {
      "affiliations": [
        "Centre of Cardiac and Vascular Diseases, Institute of Clinical medicine, Faculty of Medicine, Vilnius University Hospital, Vilnius, Lithuania"
      ],
      "name": "Jelena Celeutkiene"
    },
    {
      "affiliations": [
        "Department of Cardiology, University Hospital Galway, Galway, Ireland"
      ],
      "name": "Faisal Sharif"
    },
    {
      "affiliations": [
        "Cardiology, East Lancashire Hospitals NHS Trust, Blackburn, UK",
        "School of Medicine, University of Central Lancashire, Preston, UK"
      ],
      "name": "Scot Garg"
    },
    {
      "affiliations": [
        "CORRIB Research Centre for Advanced Imaging and Core Lab, University of Galway, Galway, Ireland"
      ],
      "name": "Vacis Tatarunas"
    },
    {
      "affiliations": [
        "CORRIB Research Centre for Advanced Imaging and Core Lab, University of Galway, Galway, Ireland"
      ],
      "name": "Yoshinobu Onuma"
    },
    {
      "affiliations": [
        "CORRIB Research Centre for Advanced Imaging and Core Lab, University of Galway, Galway, Ireland"
      ],
      "name": "Patrick W Serruys"
    }
  ],
  "title": "Diagnostic performance of exercise stress testing findings and coronary microvascular dysfunction in patients with angina with non-obstructive coronary artery disease",
  "uid": "2aea0780-4603-56b2-9442-4e0a88222a75"
}