Treating prolactinoma with dopamine agonists does not appear to result in significant valvular heart disease, though changes in valvular morphology and function may develop, according to a report.

Treating prolactinoma with dopamine agonists (DA) does not appear to result in significant valvular heart disease, though changes in valvular morphology and function may develop, according to a report in the September issue of The Journal of Clinical Endocrinology & Metabolism.

"Cabergoline can still be used in the treatment for prolactinoma, but physicians should be very careful and screen their patients with echocardiography during follow-up, and maybe even at baseline before ergot-derived DA are started, to look for unknown (congenital) valve disease," Dr. Marleen Kars told Reuters Health. "Those patients should not be treated with ergot-derived DA."

Dr. Kars, at Leiden University Medical Center, The Netherlands, and colleagues assessed the prevalence of valvular abnormalities in 78 consecutive patients with prolactinomas treated with dopamine agonists for at least one year and a mean of eight years, and in 78 matched controls.

Nine patients (12 per cent) had significant valve regurgitation of any valve, compared with 13 controls (17 per cent), the authors report.

Some degree of tricuspid valve regurgitation was present in significantly more patients taking cabergoline (24/47, 51 per cent) than control patients (22/78, 28 per cent), the report indicates, and there was a trend to more clinically relevant regurgitation of any valve in patients treated with cabergoline, compared with the patients treated with other or no dopamine agonist.

The prevalence of thickened leaflets of the mitral and aortic valves and calcifications of the mitral valve did not differ significantly between the two groups, but calcifications of the aortic valve were significantly more common in the dopamine agonist group than in the control group, because of the higher prevalence of aortic calcifications in patients treated with cabergoline.

Three patients treated with cabergoline accounted for all the patients with thickened leaflets of the tricuspid valve.

"My opinion is that all patients with prolactinoma treated with ergot-derived DA should have an echocardiography during several years of treatment, even if they are asymptomatic," Dr. Kars said.

"Further studies are necessary to determine the risk for patients treated with cabergoline longer than the period in the recent studies," Dr. Kars added. "Furthermore, studies determining the change of valve morphology before and after the use of cabergoline, for example after 1-2-5 years, are necessary."

J Clin Endocrinol Metab 2008;93:3348-3356