Our hypothesis is that Dobutamine will act in a similar fashion to Isoproterenol with respect
to cardiac conduction. Our goal is to study the effects of Dobutamine on cardiac conduction
and refractoriness during an Electrophysiology study (EPS). At the end of most EPS
Isoproterenol is commonly administered in an effort to change the conduction properties of
the heart. In our practice we have been using Dobutamine for this purpose for many years.
Dobutamine has never been rigorously studied for this indication however. We designed this
study to systematically study the effect of various doses of Dobutamine on the parameters of
cardiac conduction and refractoriness that are commonly measured during an EPS. We are
specifically looking to compare the effect that Dobutamine has on the sinus node with the
effect it has on the atrioventricular node. Patients undergoing an EPS at Long Island Jewish
Hospital will be recruited and consented. Measurements of various conduction parameters will
be taken at baseline as is standard protocol for an EPS. Dobutamine will then be administered
at doses of 5mcg/kg/min, 10mcg/kg/min, 15mcg/kg/min and 20mcg/kg/min. At each of these
dosages the same conduction parameters will be measured. A comparison will then be made
between the conduction parameters at baseline and when the Dobutamine is administered.