Effect of Sex Difference of Coronary Microvascular Dysfunction on Long-Term Outcomes in Deferred Lesions

JACC Cardiovasc Interv. 2020 Jul 27;13(14):1669-1679. doi: 10.1016/j.jcin.2020.04.002. Epub 2020 Jun 24.

Abstract

Objectives: This study investigated the sex difference of long-term cardiovascular outcomes on coronary flow reserve (CFR) and index of microcirculatory resistance (IMR) in patients with deferred coronary artery lesions.

Background: Coronary microvascular dysfunction is associated with poorer long-term outcomes. It can be assessed by CFR and the IMR.

Methods: The study prospectively enrolled 434 patients (133 women and 301 men) and analyzed CFR, IMR, fractional flow reserve, and quantitative coronary angiography. Clinical outcomes were assessed by major adverse cardiovascular event(s) (MACE) of cardiac death, myocardial infarction, and revascularization during 5 years of follow-up. The study protocol was approved by the Institutional Review Board or Ethics Committee at each participating center, and all patients provided written informed consent. The study protocol was in accordance with the Declaration of Helsinki.

Results: Women had milder epicardial disease compared with men (fractional flow reserve: 0.91 [interquartile range (IQR): 0.87 to 0.96] vs. 0.90 [IQR: 0.86 to 0.95]; p = 0.037). IMR was similar between the sexes, but CFR was lower in women (2.69 [IQR: 2.08 to 3.90] vs. 3.20 [IQR: 2.20 to 4.31]; p = 0.006) due to a shorter resting mean transit time, whereas hyperemic mean transit times were similar. At 5-year follow-up, MACE was significantly lower in women compared with men (1.1% vs. 5.5%; p = 0.017). Sex, diabetes mellitus, and CFR were independent predictors for MACE for all patients. The risk of MACE was significantly higher in men with low versus high CFR (hazard ratio: 4.58; 95% confidence interval: 1.85 to 11.30; p = 0.011) which was not seen in women.

Conclusions: There was no sex difference in microvascular function by IMR. CFR was lower in women due to a higher resting coronary flow; however, long-term clinical outcomes in deferred lesions were better in women compared with men. (Clinical, Physiological and Prognostic Implication of Microvascular Status; NCT02186093).

Keywords: coronary artery disease; coronary flow reserve; fractional flow reserve; index of microcirculatory resistance; microvascular function.

Publication types

  • Comparative Study
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Cardiac Catheterization*
  • Coronary Artery Disease / diagnosis*
  • Coronary Artery Disease / physiopathology
  • Coronary Artery Disease / therapy
  • Female
  • Fractional Flow Reserve, Myocardial*
  • Health Status Disparities
  • Healthcare Disparities
  • Humans
  • Male
  • Microcirculation*
  • Middle Aged
  • Myocardial Revascularization
  • Predictive Value of Tests
  • Prospective Studies
  • Republic of Korea
  • Risk Assessment
  • Risk Factors
  • Sex Factors
  • Time Factors
  • Time-to-Treatment
  • Treatment Outcome
  • Vascular Resistance*

Associated data

  • ClinicalTrials.gov/NCT02186093