What are the risks of CABG in hypothyroid patients?
The risks of CABG in hypothyroid patients are poorly defined. A retrospective study of hypothyroid patients undergoing CABG had a higher incidence of heart failure and gastrointestinal complications and a lower incidence of post-operative fever than did members of a matched euthyroid group.598 Patients with subclinical hypothyroidism may be at increased risk for developing AF after CABG,599 and 1 study even suggested that triiodothyronine supplementation in patients undergoing CABG (including those who are euthyroid) decreased the incidence of postoperative AF.600 Conversely, controlled studies of triiodothyronine in subjects undergoing CABG have shown no benefit.601,602 Rarely, patients may develop severe hypothyroidism after CABG, which manifests as lethargy, prolonged required ventilation, and hypotension.603 Thyroid replacement is indicated in these individuals.