# Associations of Culprit Vessel Size and Plaque Characteristics in Patients with ST-Segment Elevation Myocardial Infarction

## TL;DR

This study explores how the size of a culprit vessel and plaque characteristics relate in patients with heart attacks, finding no significant difference in clinical outcomes despite differences in plaque features.

## Contribution

The study identifies associations between culprit vessel size and plaque characteristics in STEMI patients using OCT imaging.

## Key findings

- Patients with larger culprit vessel diameters showed higher incidence of plaque rupture and macrophage presence.
- Clinical outcomes (MACEs) did not differ significantly among groups with different vessel diameters and plaque phenotypes.
- Culprit vessel size is significantly associated with plaque phenotype in STEMI patients.

## Abstract

Small vessel disease (SVD) widely exists in patients with
acute coronary syndrome. However, the plaque characteristic of SVD has not been
investigated.

Optical coherence tomography (OCT) of culprit
lesion was examined in 576 patients with ST-segment elevation myocardial
infarction (STEMI) and finally 404 patients with qualified images were analysed of plaque
phenotypes and microstructure. The cohort was divided into three groups according
to vessel diameters of culprit lesion which were measured by OCT. Major adverse
cardiac events (MACEs) were recorded of each patient and compared among patients
with different vessel diameters and plaque phenotypes.

Gender,
age and body mass index (BMI) were significantly different among patients with
different diameters of culprit vessels (98.4% vs. 85.7% vs.71.4%, p
< 0.001; 40.0 ± 7.0 vs. 54.9 ± 6.6 vs. 68.9 ± 5.8, p
< 0.001; 28.4 ± 4.0 vs. 25.8 ± 2.9 vs. 25.2 ± 3.0, p
< 0.001, respectively). Moreover, patients with diameters of culprit lesion
>3 mm presented with more incidence of plaque rupture and macrophage (57.7%
vs. 42.1% vs. 46.2%, p = 0.015, 55.1% vs. 41.0% vs. 36.9%,
p = 0.010). Total MACE did not differ among groups of different vessel
diameters and plaque phenotypes.

Vessel size of culprit
lesion is significantly associated with plaque phenotype in patients with STEMI.
However, patients with different diameters and plaque phenotypes showed no
significant difference of clinical outcomes.

NCT03593928.