Dopamine agonists and valvular heart disease.

PURPOSE OF REVIEW

Dopamine agonists are first-line therapy for prolactinomas, normalizing serum prolactin and reducing tumor size in the majority of cases. Recent studies reporting cardiac valvular abnormalities in dopamine agonist-treated Parkinson's disease patients have raised concerns regarding potential cardiac effects in dopamine agonist-treated prolactinoma patients. This article reviews the current literature regarding dopamine agonist use and cardiac valve disease and provides guidance for clinical practice.

RECENT FINDINGS

Off-target action of dopamine agonists at 5-hydroxytryptamine 2B receptors is now recognized to cause cardiac valve disease in several studies in Parkinson's disease patients who received high daily dopamine agonist doses, including cabergoline and pergolide. Generally, dopamine agonist doses in prolactinoma therapy are 10-fold lower than those employed in Parkinson's disease, although occasionally dopamine agonist-resistant patients require higher doses. Most studies of dopamine agonist use in prolactinoma have not observed valvular abnormalities.

SUMMARY

Dopamine agonists are effective in treating prolactinomas. At typical doses, the risk for valvulopathy appears low. Increased risk of cardiac valvulopathy should be considered in patients requiring higher doses or long duration of therapy. Echocardiography should be performed in these high-risk patients, drug holidays implemented and patients withdrawn from these agents if possible.