Background: The use of high dose Ergot derived dopamine agonists in patients with Parkinsons disease has been associated with an increased risk of cardiac valvular fibrosis. The UK Medicines and Health products Regulatory Agency (MHRA) currently advises baseline Echocardiogram within 36 months and follow up Echocardiogram at 612 monthly intervals in all patients taking ergot derived dopamine agonists. However, the risk of cardiac valvulopathy with lower doses used to treat prolactinomas remains unclear.
The aims of this study were to audit our adherence to the MHRA guidance in patients treated with ergot derived dopamine agonists for prolactinoma and to determine the prevalence of valvular heart disease in this cohort of patients.
Methods: Retrospective casenote review (n=48) of patients with prolactinoma on Cabergoline (n=42) or Bromocriptine (n=6) attending Endocrine clinic. Thirty-six were already on treatment prior to the publication of MHRA drug safety advice. Seventeen patients were on treatment for >5 years, 26 under 5 years, four <6 months and one of unknown duration.
The median Cabergoline does was 500 μg/week and Bromocriptine 1.88 mg/day.
Results: Thirty-five patients (72.9%) had a baseline echocardiogram of whom 22 (62.8%) had a normal result and 13 had (37.50%) mild/trivial TR, AR or MR. Thirteen patients had not had an echocardiogram.
None had follow up echocardiograms; 26 were not due (<12 months of baseline ECHO), one discontinued cabergoline and no reason documented in 7.
Conclusion: 83.33% patients diagnosed after the MHRA advice had baseline echocardiograms within 6 months of treatment. Sixty-six percent patients on treatment predating MHRA advice had an echocardiogram as soon as the advice was published. In contrast to treatment with high dose cabergoline in patients with Parkinsons disease no significant cardiac valvular dysfunction was found on echocardiogram in patients with prolactinoma treated with low-dose dopamine agonists.