Coronary morphological and functional features in subclinical hypothyroidism with ST-Elevation myocardial infarction.

BACKGROUND

Subclinical hypothyroidism (SH), characterized by normal free tetraiodothyronine (FT4) but high hyroid-stimulating hormone (TSH), gains attention for relationship with cardiovascular diseases. This study aims to investigate coronary artery features of non-culprit lesions in SH patients with ST-elevation myocardial infarction (STEMI) to understand their intracoronary morphological and functional characteristics.

METHODS

A retrospective study of 1,570 STEMI patients with ≥ 50% non-culprit lesions analyzed coronary angiography, optical coherence tomography (OCT) imaging, & quantitative flow ratio (QFR) data. Patients were grouped based on SH status.

RESULTS

Among them, a total of 214 patients had SH. In baseline characteristics, the SH group showed lower male and smoker rates, lower free triiodothyronine (FT3), and higher high-sensitivity C-reactive protein (hs-CRP), N terminal pro B-type natriuretic peptide (NT-proBNP), and TSH levels than the non-SH group. SH group had longer lesions, more micro-vessels, more cholesterol crystals, and lower QFR values for non-culprit lesions. Additionally, SH was an independent predictor for coronary parameters including micro-vessel, cholesterol crystal, and QFR values ≤ 0.8. And the effect of SH on those coronary parameters did not show any interaction in different subgroups.

CONCLUSIONS

There was an association between SH and specific coronary artery characteristics, including increased plaque inflammation and plaque instability (the increase of micro-vessels and cholesterol crystal detected by OCT) and potential endothelial dysfunction (the decrease of QFR value detected by QFR). Our forthcoming research will prioritize extensive, multi-center prospective studies aimed at elucidating the precise mechanisms and long-term prognosis of SH on coronary artery lesions.