Pulmonary hypertension is frequent in hyperthyroidism and normalizes after therapy

Area of Science:

• Cardiology
• Endocrinology
• Pulmonology

Background:

• Growing evidence suggests a link between hyperthyroidism and pulmonary hypertension.
• This study investigates the prevalence of pulmonary hypertension in hyperthyroid patients.

Purpose of the Study:

• To evaluate the prevalence of pulmonary hypertension in hyperthyroidism.
• To determine the role of methimazole in regulating pulmonary vascular resistance.

Main Methods:

• 114 hyperthyroid patients (47 Graves', 67 nodular goiter) and 20 controls underwent Doppler echocardiography.
• Systolic pulmonary artery pressure (PAPs) was measured. Patients with pulmonary hypertension were followed for 120 days.
• Subgroups received either methimazole (1A) or partial thyroidectomy (1B).

Main Results:

• Mild pulmonary hypertension was found in 43% of hyperthyroid patients (mean PAPs 27.77 mmHg) vs. 0% in controls (mean PAPs 21.32 mmHg).
• A significant negative correlation existed between T.S.H. levels and PAPs (r=-0.85, p<0.001).
• Methimazole treatment led to a rapid PAPs reduction (34.3 to 29.2 mmHg in 15 days), while thyroidectomy showed no significant change (34.3 to 34.1 mmHg).

Conclusions:

• Hyperthyroidism is frequently associated with mild, transient pulmonary hypertension.
• Methimazole treatment results in a faster decrease in pulmonary artery pressure compared to partial thyroidectomy.