All drugs capable to activate β1 myocardial receptors may potentially have some proarrhythmic action, by increasing intracellular Ca++ and cyclic AMP. Ibopamine, an orally active dopamine-related drug, acts mainly on dopaminergic postjunctional DA1 receptors eliciting a direct dilating effect on several vascular beds, and presynaptic DA2 and α2 adrenergic receptors, by reducing the release of norepinephrine from sympathetic nerve endings. Ibopamine acts also, although modestly, on β1 myocardial adrenergic receptors (which are however down regulated in CHF) and should theoretically elicit some troubles of rhythm. Many studies were carried out to evaluate the effect of ibopamine on heart rate, cardiac rhythm and electrical safety during electrophysiological studies, or during ambulatory Holter monitoring for 24 or 48 hours, or by observing the incidence of sudden death in, long-term controlled or uncontrolled studies. Ibopamine was used at doses ranging between 50 mg t.i.d. and 200 mg t.i.d. The results show that in patients with CHF and troubles of rhythm ibopamine does not have a significant proal rhythmic effect and sudden death is not increased with ibopamine treatment. A possible explanation for the absence of negative influence of ibopamine on cardiac rhythm could lie in the reduction of norepinephrine plasma levels and the decrease in left ventricle wall stress.
|Number of pages||6|
|Journal||New Trends in Arrhythmias|
|Publication status||Published - 1994|
- Arrhythmogenic effect
- Congestive heart failure
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine