Clinical phenotypes and prognosis of thyrotoxic heart failure and cardiomyopathy in patients hospitalized for acute heart failure

BACKGROUND: We sought to examine clinical characteristics and outcomes in patients hospitalized for acute heart failure (HF) and thyrotoxicosis. METHODS: Patients with thyrotoxic HF were compared with age and gender‐matched patients hospitalized for acute HF (controls). Thyr‐HF was defined by the Framingham criteria for HF and clinical hyperthyroidism. Thyrotoxic cardiomyopathy was defined as left ventricular ejection fraction (LVEF) < 55%. RESULTS: Of 11 109 consecutive patients hospitalized for acute HF between 1 January 2002 and 1 January 2017, 92 patients (0.8%) had thyrotoxic HF. Clinical and echocardiographic data were available in 87 patients (age 51 ± 16 years; 74% female), representing the study population. Compared with controls, patients with Thyr‐HF had a smaller body surface area (BSA), a higher LVEF, a lower LV end‐diastolic diameter, a higher tricuspid annular plane systolic excursion (TAPSE), higher blood pressure, higher heart rate, and were more likely to have right‐sided HF at presentation (P < 0.01 for all). The survival rate among patients with thyrotoxic HF was higher than the control group (HR: 4.3; 95% CI: 2.1–9.5). Fifty‐eight percent of patients with thyrotoxic HF had thyrotoxic cardiomyopathy. In multivariate analysis, TAPSE (OR = 46; 95% CI: 1.04–2008.20; P = 0.047) and leukocytosis (OR = 16; 95% CI 1.01–259.39; P = 0.049) correlated with thyrotoxic cardiomyopathy. LV recovery was observed in 69% of these patients. CONCLUSIONS: Thyrotoxic HF was uncommon among patients hospitalized for acute HF. However, after definitive therapy, these patients had a more favourable prognosis than those hospitalized for acute HF without thyrotoxic HF. Clinical phenotypes of thyrotoxic HF include small BSA, middle‐aged female, HF‐pEF, and right‐sided HF. Thyrotoxic cardiomyopathy affected over half of the patients with thyrotoxic HF with a two‐third recovery rate.