Thyroid hormone affects the metabolism of all tissues in the body. The aim of this study was to analyze the prevalence and implications of thyroid disorders in a cohort of consecutive patients with spontaneous coronary artery dissection (SCAD).

A total of 73 patients with SCAD were analyzed. Baseline characteristics and clinical outcomes were compared between euthyroid and hypothyroid patients. Subsequently, the prevalence of thyroid function abnormalities and the clinical characteristics of SCAD patients were compared with those in 73 patients with acute coronary syndrome but without SCAD, matched by age, sex, and presentation.

Mean age was 55 ± 12 years and 26% had hypothyroidism. Compared with patients with normal thyroid function, patients with SCAD and hypothyroidism were all women (100% vs 69%, P = .01), more frequently had dissection in distal (74% vs 41%, P = .03) and tortuous coronary segments (68% vs 41%, p = .03), and more frequently received conservative medical management (79% vs 41%, P = .007). During a mean clinical follow-up of 4.1 ± 3.8 years, 23% of the patients had adverse cardiac events irrespective of thyroid function status. The prevalence of hypothyroidism was higher in patients with SCAD than in matched patients with acute coronary syndrome without SCAD (26% vs 8%, P = .004).

There is a high prevalence of hypothyroidism in patients with SCAD. Patients with SCAD and hypothyroidism are more frequently women, more frequently have distal dissections in tortuous vessels, and are more frequently managed with a conservative medical strategy.