[Thyroid gland and the heart : Pathophysiological background, diagnostic and therapeutic consequences]

Area of Science:

• Cardiology
• Endocrinology
• Internal Medicine

Background:

• Thyroid dysfunction is common and linked to cardiovascular disease.
• Observational studies indicate a connection between thyroid disorders and cardiovascular morbidity/mortality.

Purpose of the Study:

• To critically review the relationship between thyroid dysfunction and heart conditions.
• To outline treatment recommendations for co-occurring thyroid and cardiac disorders.

Main Methods:

• Literature search conducted in PubMed and Medline.

Main Results:

• Overt and subclinical hyperthyroidism are associated with cardiovascular risks, though interventional data is limited.
• Basic thyroid diagnostics are advised for cardiovascular disease.
• Overt hyperthyroidism and hypothyroidism require immediate treatment.
• Subclinical thyroid dysfunction needs laboratory confirmation.
• Treatment for subclinical hyperthyroidism with heart disease is beneficial (e.g., radioiodine therapy).
• Treatment thresholds for subclinical hypothyroidism remain debated; levothyroxine is typically initiated for TSH > 10 mIU/L.
• Baseline thyroid assessment is essential before amiodarone treatment or if general condition deteriorates.

Conclusions:

• Thyroid function significantly influences cardiovascular health.
• Management strategies differ for overt versus subclinical thyroid dysfunction.
• Individualized treatment approaches are necessary, especially for subclinical hypothyroidism.