Cardiac effects of pergolide.

We examined the effect of pergolide, a semisynthetic ergot alkaloid, alone or combined with carbidopa and levodopa (Sinemet), on the cardiac rhythm of 12 patients with Parkinson's disease. The patients were selected on the basis of severe Parkinson's disease and stable cardiac rhythm as determined by 1 to 5 days of Holter monitoring. Monitoring was then carried out for an additional period of between 2 and 10 wk while the patients were on pergolide. Seven of the 12 patients had repetitive ventricular rhythms (RVRs). These were isolated, infrequent, and not associated with increases in premature ventricular contractions. The dose at which the RVRs occurred may be a function of the presence or absence of heart disease, but the significance of RVRs remains to be determined.