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Published on: March 27, 2018
Subclinical Hypothyroidism as a Risk for Coronary Artery Bypass Grafting
Ricardo Mendes Martins1,2, Felipe José M Pittella2, Beatriz C de Oliveira1
1Department of Internal Medicine, Federal Fluminense University, Niteroi, Rio de Janeiro, Brazil, uff.br.
Subclinical hypothyroidism (SH) increases the risk of major adverse cardiovascular events (MACE) and postoperative complications, including stroke and atrial fibrillation, in patients undergoing coronary artery bypass grafting (CABG). Euthyroid patients experienced fewer adverse outcomes.
Area of Science:
- Cardiology
- Endocrinology
- Cardiovascular Surgery
Background:
- The established link between hypothyroidism and cardiovascular disease (CVD) is known.
- Limited data exist on subclinical hypothyroidism (SH) and its impact on major adverse cardiovascular events (MACE) and postoperative complications after coronary artery bypass grafting (CABG).
Purpose of the Study:
- To investigate the association between subclinical hypothyroidism (SH) and the risk of MACE and postoperative complications in patients undergoing CABG.
- To compare outcomes between patients with SH and euthyroid patients after CABG.
Main Methods:
- A cohort of 863 patients undergoing CABG between 2010 and 2019 was analyzed.
- Primary outcomes included MACE (all-cause death, cardiovascular death, stroke, acute myocardial infarction, new revascularization) and postoperative complications (atrial fibrillation, pleural effusion, pericardial effusion, infections, mediastinitis).
Main Results:
- Patients with SH exhibited significantly higher rates of MACE (20.3% vs. 8.2%) and stroke (10.2% vs. 3.0%) compared to euthyroid patients.
- Postoperative complications were more frequent in the SH group, including atrial fibrillation (18.6% vs. 9.7%), pleural effusion (52.6% vs. 19.2%), pericardial effusion (20.3% vs. 7.8%), and infections (28.8% vs. 16.9%).
- No significant differences were observed in all-cause death, cardiovascular death, acute myocardial infarction, new revascularization, or mediastinitis.
Conclusions:
- Subclinical hypothyroidism is associated with an increased risk of MACE and several postoperative complications following CABG.
- These findings highlight the importance of considering SH as a risk factor in patients undergoing cardiovascular surgery.
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