From the Department of Cardiovascular Disease, Tianjin Chest Hospital, the Affiliated Hospital of Tianjin University and Nankai University, the Clinical College of Tianjin Medical University, Tianjin, China; Tianjin Institute of Cardiovascular Diseases, Tianjin Chest Hospital, Tianjin, China.
From the Department of Cardiovascular Disease, Tianjin Chest Hospital, the Affiliated Hospital of Tianjin University and Nankai University, the Clinical College of Tianjin Medical University, Tianjin, China; Tianjin Institute of Cardiovascular Diseases, Tianjin Chest Hospital, Tianjin, China.
Endocr Pract. 2020 Aug;26(8):840-845. doi: 10.4158/EP-2019-0600.
After an intravenous bolus injection of 100 mL of iodinated contrast agent (370 mgI/mL), the amount of iodine atoms entering the blood is tens of thousands of times the daily dose of iodine recommended by the World Health Organization. However, the effect of iodinated contrast in patients with nonthyroidal illness, manifested as reduced serum total triiodothyronine (TT3) concentrations, is unclear. We studied the effect of iodinated contrast on thyroid function and auto-antibodies in patients with reduced TT3 after diagnosis and treatment of coronary heart disease.
This was a prospective cohort study. One hundred and fifty-four stable angina pectoris patients with reduced TT3 and normal thyroid-stimulating hormone (TSH), free thyroxine (FT4), and reverse triiodothyronine (rT3) were enrolled from January, 2017, to June, 2018. All subjects had no history of thyroid dysfunction and had no recent infections, tumors, trauma, or other critical illnesses. Fourty-one patients underwent coronary angiography and 113 patients underwent coronary intervention.
There were 6 patients (3.9%) with hypothyroidism and 30 patients (19.5%) developed subclinical hypothyroidism (SCHypo) on the first day after surgery. There were 6 patients (3.9%) with hypothyroidism, 6 patients (3.9%) with SCHypo, and 18 patients (11.7%) with subclinical hyperthyroidism (SCHyper) at the first month postsurgery. There were 23 patients (14.9%) with SCHyper and 6 patients (3.9%) with SCHypo at the sixth month after surgery. No patient with longterm severe thyroid dysfunction occurred during follow-up. The levels of free triiodothyronine, FT4, TT3, total thyroxine, and TSH showed statistically significant changes at 1 day, and 1, 3, and 6 months postoperative (P<.005). The level of rT3 showed no statistically significant change at 1, 3, and 6 months postoperative (P>.05). The levels of thyroglobulin antibody and thyroid peroxidase antibody decreased at 6 months postoperative (P<.001).
The risk of subclinical thyroid dysfunction and transient hypothyroidism occurred with a single large dose of iodinated contrast in the diagnosis and treatment of coronary heart disease, but no longterm severe thyroid dysfunction occurred. Patients with preoperative thyroid antibody elevation were more likely to have subclinical thyroid dysfunction after surgery.
FT3 = free triiodothyronine; FT4 = free thyroxine; PCI = percutaneous coronary intervention; rT3 = reverse triiodothyronine; SCHyper = subclinical hyperthyroidism; SCHypo = subclinical hypothyroidism; TGAB = thyroglobulin antibody; TPOAB = thyroid peroxidase antibody; TT3 = total triiodothyronine; TT4 = total thyroxine; TSH = thyroid-stimulating hormone; WHO = World Health Organization.
静脉推注 100 毫升碘造影剂（370mgI/mL）后，进入血液的碘原子数量是世界卫生组织推荐的碘每日剂量的数万倍。然而，碘造影剂在非甲状腺疾病患者中的作用，表现为血清总三碘甲状腺原氨酸（TT3）浓度降低，其作用尚不清楚。我们研究了碘造影剂对冠心病诊断和治疗后 TT3 降低的患者甲状腺功能和自身抗体的影响。
这是一项前瞻性队列研究。2017 年 1 月至 2018 年 6 月，共纳入 154 例 TT3 降低且甲状腺刺激激素（TSH）、游离甲状腺素（FT4）和反三碘甲状腺原氨酸（rT3）正常的稳定型心绞痛患者。所有患者均无甲状腺功能障碍病史，且无近期感染、肿瘤、创伤或其他急危重症。41 例患者行冠状动脉造影检查，113 例行冠状动脉介入治疗。
术后第 1 天，6 例（3.9%）患者出现甲状腺功能减退，30 例（19.5%）患者发生亚临床甲状腺功能减退（SCHypo）。术后第 1 个月，6 例（3.9%）患者出现甲状腺功能减退，6 例（3.9%）患者出现 SCHypo，18 例（11.7%）患者出现亚临床甲状腺功能亢进（SCHyper）。术后第 6 个月，23 例（14.9%）患者出现 SCHyper，6 例（3.9%）患者出现 SCHypo。随访期间无长期严重甲状腺功能障碍患者。游离三碘甲状腺原氨酸、FT4、TT3、总甲状腺素和 TSH 水平在术后 1 天和 1、3、6 个月时均有统计学意义（P<.005）。rT3 水平在术后 1、3 和 6 个月时无统计学意义（P>.05）。术后 6 个月时，甲状腺球蛋白抗体和甲状腺过氧化物酶抗体水平下降（P<.001）。
在诊断和治疗冠心病时，单次大剂量碘造影剂会导致亚临床甲状腺功能障碍和短暂性甲状腺功能减退，但不会导致长期严重的甲状腺功能障碍。术前甲状腺抗体升高的患者术后更易发生亚临床甲状腺功能障碍。
