{
  "abstract": "Background Lipoprotein-a [Lp(a)] is an established marker of epicardial coronary disease, yet its association with coronary microvascular dysfunction (CMD) is largely unexplored. COMET-19 enrolled 117 patients who developed angina following severe COVID-19 but had no obstructive coronary artery disease (ANOCA). Each participant underwent invasive coronary physiology testing—fractional flow reserve (FFR), coronary flow reserve (CFR) and index of microvascular resistance (IMR)—to identify CMD (CFR<2.0 or IMR≥25), and functional CMD (CFR<2.0 with IMR<25).Methods We retrospectively analysed the COMET-19 cohort comparing LP(a) to CMD and endothelial cell dysfunction (ECD) guideline cut-off values of the American Heart Association (AHA/ACC) [≥125 nmol/L], Canadian Cardiovascular Society (CCS) [≥100 nmol/L], European Atherosclerotic Society (EAS) intermediate level [50–125 nmol/L] or higher level [>125 nmol/L] and the National Lipid Association (NLA) [>100 nmol/L]). Pearson Chi-Square, Spearman Correlation and Odds Ratios were calculated using SPSS v29.Results The mean(SD) age was 65.95(11.4). The median(min-max) Lp(a) was 194 nmol/L (45–499). We could not demonstrate a relationship between elevated Lp(a) and the presence of CMD (CFR or IMR values) (p>0.05). Elevated Lp(a) values did not increase the risk of CMD or ECD across ACC/AHA, CCS, EAS or NLA thresholds (all OR 0.2–1.5: 95% CI crossed unity). There was no correlation between Lp(a) and CMD diagnostic criteria (CFR: ρ= -0.05, p=0.63), (IMR: ρ=0.04, p=0.69) ( figure 1).Conclusion A raised serum LP(a) was not associated with increased risk of, or incidence of CMD independent of the LP(a) cut off value criterion employed. LP(a) was not a helpful test to risk-stratify patients for CMD, in this cohort.Abstract 8 Figure 1",
  "authors": [
    {
      "affiliations": [
        "University Hospital Limerick, Limerick, Ireland"
      ],
      "name": "M McKittrick"
    },
    {
      "affiliations": [
        "University Hospital Limerick, Limerick, Ireland"
      ],
      "name": "S McKittrick"
    },
    {
      "affiliations": [
        "University Hospital Limerick, Limerick, Ireland"
      ],
      "name": "T Kiernan"
    },
    {
      "affiliations": [
        "University Hospital Limerick, Limerick, Ireland"
      ],
      "name": "A Aldujeli"
    }
  ],
  "title": "8 Is LP(a) a predictor of coronary microvascular dysfunction? A retrospective analysis of the COMET-19 study",
  "uid": "0368c051-cb3b-57fa-a6ec-793c271b4884"
}