The association between Takotsubo cardiomyopathy and thyrotoxicosis: A systematic review

Purpose This study aims to review all published cases on the association between thyrotoxicosis and Takutsubo Syndrome by describing clinical characteristics, diagnostic work-up, treatment, and outcome. Methods We searched PubMed and Embase databases from inception to the 17th of February 2022 for case reports or series reporting the above-mentioned association. We extracted data on demographic characteristics, clinical features, diagnostic work-up, treatment, and clinical outcomes. Cases were stratified into groups based on the presumed cause of the thyrotoxicosis (iatrogenic vs non-iatrogenic and Graves' diseases vs non-Graves' disease, respectively). Results We identified 25 cases from 24 articles. The mean age was 61.7 years (+/- SD 14.5). Most patients were women (88%). Graves' disease (52%) was the leading cause of thyrotoxicosis. Previous cancer was significantly more common in patients with iatrogenic thyrotoxicosis (P = 0.03). The most common symptoms were respiratory symptoms (68%), chest pain (56%), and palpitations (40%). The most common ECG characteristics were T-wave abnormalities (48%) and ST-elevations (36%). Elevated troponin levels were found in 92% of the cases. Patients with Graves's disease and Takutsubo Syndrome had higher plasma levels of serum thyroxine (P = 0.03) and were more often treated with beta-blockers (P = 0.01) compared to patients with thyrotoxicosis of other origins. Notably, 40% of cases experienced in-hospital complications. No deaths were reported. All patients had improved cardiac function within a median follow-up of 42 days. Conclusion Evidence-based on current case reports suggests an increased risk of Takutsubo Syndrome and subsequently increased risk of in-hospital complications in patients with thyrotoxicosis.