Objective: Treatment with ergot-derived dopamine agonists, pergolide, and cabergoline has been associated with an increased frequency of valvular heart disease in Parkinson's disease. The aim of the present study was to assess the prevalence of valvular heart disease in patients treated with dopamine agonists for prolactinomas. Design: This was a cross-sectional study. Patients: We performed two-dimensional and Doppler echocardiography in 78 consecutive patients with prolactinoma ( mean age 47 +/- 1.4 yr, 26% male, 31% macroprolactinoma) treated with dopamine agonists for at least 1 yr ( mean 8 +/- 0.6 yr) and 78 control subjects. Patients were classified according to treatment: patients treated with cabergoline ( group 1: n = 47) and patients not treated with cabergoline ( group 2: n = 31). Results: Clinically relevant valvular heart disease was present in 12% of patients (nine of 78) vs. 17% of controls ( 13 of 78) ( P = 0.141) and 17% ( eight of 47) of patients treated with cabergoline vs. 3% ( one of 31) of patients not treated with cabergoline ( P = 0.062). Mild tricuspid regurgitation was present in 41% of patients vs. 26% of controls ( P = 0.042), and aortic valve calcification was present in 40% of patients, compared with 18% of controls ( P = 0.003). There was no relation between the cumulative dose of cabergoline and the presence of mild, moderate, or severe valve regurgitation. Conclusion: Several years of dopamine agonist treatment in patients with prolactinomas is associated with increased prevalence of aortic valve calcification and mild tricuspid regurgitation but not with clinically relevant valvular heart disease. Therefore, additional studies on the adverse cardiac effects of dopaminergic drugs in prolactinoma are warranted, especially in patients with much longer use of these drugs.