Impact of Coronary Microvascular Dysfunction on Functional Left Ventricular Remodeling and Diastolic Dysfunction

Abstract

Background: Coronary microvascular dysfunction (CMD) is a common complication of ST-segment-elevation myocardial infarction (STEMI) and can lead to adverse cardiovascular events. Whether CMD after STEMI is associated with functional left ventricular remodeling (FLVR) and diastolic dysfunction, has not been investigated.

Methods and results: This is a nonrandomized, observational, prospective study of patients with STEMI with multivessel disease. Coronary flow reserve and index of microcirculatory resistance of the culprit vessel were measured at 3 months post-STEMI. CMD was defined as index of microcirculatory resistance ≥25 or coronary flow reserve <2.0 with a normal fractional flow reserve. We examined the association between CMD, LV diastolic dysfunction, FLVR, and major adverse cardiac events at 12-month follow-up. A total of 210 patients were enrolled; 59.5% were men, with a median age of 65 (interquartile range, 58-76) years. At 3-month follow-up, 57 patients (27.14%) exhibited CMD. After 12 months, when compared with patients without CMD, patients with CMD had poorer LV systolic function recovery (-10.00% versus 8.00%; P<0.001), higher prevalence of grade 2 LV diastolic dysfunction (73.08% versus 1.32%; P<0.001), higher prevalence of group 3 or 4 FLVR (11.32% versus 7.28% and 22.64% versus 1.99%, respectively; P<0.001), and higher incidence of major adverse cardiac events (50.9% versus 9.8%; P<0.001). Index of microcirculatory resistance was independently associated with LV diastolic dysfunction and adverse FLVR.

Conclusions: CMD is present in ≈1 of 4 patients with STEMI during follow-up. Patients with CMD have a higher prevalence of LV diastolic dysfunction, adverse FLVR, and major adverse cardiac events at 12 months compared with those without CMD.

Registration: URL: https://www.clinicaltrials.gov; Unique Identifier: NCT05406297.

Keywords: ST‐segment–elevation myocardial infarction; cardiac diastolic dysfunction; coronary flow reserve; coronary microvascular dysfunction; index of microvascular resistance; left ventricular functional remodeling; percutaneous coronary intervention.

Figure 1. Impact of coronary microvascular dysfunction (CMD) on left ventricular ejection fraction (LVEF) over a 12‐month period.

A, Box plot of LVEF at 12‐month follow‐up, categorized by CMD. B, The 12‐month change in LVEF, categorized by CMD. PCI indicates percutaneous coronary intervention.

Figure 2. Evolution of diastolic dysfunction grades following percutaneous coronary intervention (PCI) over 12 months in relation to coronary microvascular dysfunction (CMD).

A, Alluvial plot illustrating the dynamic changes in diastolic dysfunction during the 12‐month follow‐up. B, Alluvial plot illustrating the dynamic changes in diastolic dysfunction during the 12‐month follow‐up in patients with no evidence of CMD. C, Alluvial plot illustrating the dynamic changes in diastolic dysfunction during the 12‐month follow‐up in patients with evidence of CMD.

Figure 3. Prevalence of diastolic dysfunction at 12 months displayed by coronary microvascular dysfunction (CMD).

Figure 4. Rates of left ventricular (LV) remodeling displayed by coronary microvascular dysfunction (CMD).

Figure 5. Rates of major adverse cardiac events (MACEs; composite of stroke, nonfatal myocardial infarction [MI], revascularization, heart failure hospitalization, and cardiovascular death) and individual components displayed by coronary microvascular dysfunction (CMD).

TVR indicates target vessel revascularization.

Figure 6. Kaplan‐Meier event‐free survival curve for occurrence of major adverse cardiac events grouped by coronary microvascular dysfunction (CMD).