Comparative Prognostic Utility of Indexes of Microvascular Function Alone or in Combination in Patients with an Acute ST-Segment-Elevation Myocardial Infarction

  • David Carrick
  • , Caroline Haig
  • , Nadeem Ahmed
  • , Jaclyn Carberry
  • , Vannesa Teng Yue May
  • , Margaret McEntegart
  • , Mark C. Petrie
  • , Hany Eteiba
  • , Mitchell Lindsay
  • , Stuart Hood
  • , Stuart Watkins
  • , Andrew Davie
  • , Ahmed Mahrous
  • , Ify Mordi
  • , Ian Ford
  • , Aleksandra Radjenovic
  • , Keith G. Oldroyd
  • , Colin Berry

    Research output: Contribution to journalArticlepeer-review

    175 Citations (Scopus)
    242 Downloads (Pure)

    Abstract

    Background: Primary percutaneous coronary intervention is frequently successful at restoring coronary artery blood flow in patients with acute ST-segment-elevation myocardial infarction; however, failed myocardial reperfusion commonly passes undetected in up to half of these patients. The index of microvascular resistance (IMR) is a novel invasive measure of coronary microvascular function. We aimed to investigate the pathological and prognostic significance of an IMR>40, alone or in combination with a coronary flow reserve (CFR≤2.0), in the culprit artery after emergency percutaneous coronary intervention for acute ST-segment-elevation myocardial infarction. Methods: Patients with acute ST-segment-elevation myocardial infarction were prospectively enrolled during emergency percutaneous coronary intervention and categorized according to IMR (≤40 or >40) and CFR (≤2.0 or >2.0). Cardiac magnetic resonance imaging was acquired 2 days and 6 months after myocardial infarction. All-cause death or first heart failure hospitalization was a prespecified outcome (median follow-up, 845 days). Results: IMR and CFR were measured in the culprit artery at the end of percutaneous coronary intervention in 283 patients with ST-segment-elevation myocardial infarction (mean±SD age, 60±12 years; 73% male). The median IMR and CFR were 25 (interquartile range, 15-48) and 1.6 (interquartile range, 1.1-2.1), respectively. An IMR>40 was a multivariable associate of myocardial hemorrhage (odds ratio, 2.10; 95% confidence interval, 1.03-4.27; P=0.042). An IMR>40 was closely associated with microvascular obstruction. Symptom-to-reperfusion time, TIMI (Thrombolysis in Myocardial Infarction) blush grade, and no (≤30%) ST-segment resolution were not associated with these pathologies. An IMR>40 was a multivariable associate of the changes in left ventricular ejection fraction (coefficient, -2.12; 95% confidence interval, -4.02 to -0.23; P=0.028) and left ventricular end-diastolic volume (coefficient, 7.85; 95% confidence interval, 0.41-15.29; P=0.039) at 6 months independently of infarct size. An IMR>40 (odds ratio, 4.36; 95% confidence interval, 2.10-9.06; P<0.001) was a multivariable associate of all-cause death or heart failure. Compared with an IMR>40, the combination of IMR>40 and CFR≤2.0 did not have incremental prognostic value. Conclusions: An IMR>40 is a multivariable associate of left ventricular and clinical outcomes after ST-segment-elevation myocardial infarction independently of the infarction size. Compared with standard clinical measures of the efficacy of myocardial reperfusion, including the ischemic time, ST-segment elevation, angiographic blush grade, and CFR, IMR has superior clinical value for risk stratification and may be considered a reference test for failed myocardial reperfusion.

    Original languageEnglish
    Pages (from-to)1833-1847
    Number of pages15
    JournalCirculation
    Volume134
    Issue number23
    DOIs
    Publication statusPublished - 6 Dec 2016

    Keywords

    • magnetic resonance imaging
    • microcirculation
    • myocardial infarction
    • prognosis

    ASJC Scopus subject areas

    • Cardiology and Cardiovascular Medicine
    • Physiology (medical)

    Fingerprint

    Dive into the research topics of 'Comparative Prognostic Utility of Indexes of Microvascular Function Alone or in Combination in Patients with an Acute ST-Segment-Elevation Myocardial Infarction'. Together they form a unique fingerprint.

    Cite this