Cardiothyreosis: Epidemiological, clinical and therapeutic approach

Cardiothyreosis corresponds to the cellular effects of free thyroid hormones on the vascular wall and the myocardium. We aim to describe the clinical, para-clinical and therapeutic aspects of cardiothyreosis and to detail prognostic factors.

We conducted a descriptive retrospective study at the Endocrinology-Diabetology Department of the Hedi Chaker University Hospital in Sfax-Tunisia. We collected medical records of 100 patients with cardiothyreosis between January 1999 and December 2019. We included patients with cardiothyreosis who underwent adequate cardiac evaluation. We excluded patients with cardiac abnormalities related to conditions other than hyperthyroidism, patients who died and patients without cardiothyreosis.

We included 100 adult patients (43 men and 57 women). The mean age was 49.3 ±12.9 years (20-79 years). The diagnosis of cardiothyreosis was concomitant with that of hyperthyroidism in 72% of cases. Weight loss and palpitations were the two most frequently reported signs in 91% of cases each. Hypertension was systolic in 15 patients. The average heart rate was 103.1 beats/min (52-182 bpm). The mean TSH and FT4 levels were 0.042 μIU/ml and 59.6 pmol/l, respectively. Rhythm disorders and heart failure were the most common cardiac complications with 81 and 56 cases, respectively. Cardiac ultrasound showed dilatation of the left atrium in 28.3% of patients. Pulmonary arterial hypertension was present in 43% of cases. 57 patients had been treated with benzylthiouracil at a mean dose of 157.45 mg/day. Radical treatment with radioactive iodine was indicated in 81 patients. The evolution of cardiothyreosis was favourable in 58 patients.

Cardiothyreosis is a serious complication of hyperthyroidism. Future prospective studies will be of great help to better characterise and manage cardiothyreosis.