Study With Aminophylline to Attenuate of the Side Effects of Regadenoson

A Randomized Double-Blind Placebo Controlled Study With Aminophylline to Attenuate the Side Effect Profile of Regadenoson in Patients Undergoing Myocardial Perfusion Imaging.

The routine administration of 75 mg of intravenous aminophylline following regadenoson (Lexiscan®), a commonly used medication for nuclear stress testing of the heart, can reduce the gastrointestinal (diarrhea and stomach upset) and other side effects related to regadenoson.

Approximately 250 patients who are referred for a nuclear stress testing of the heart with regadenoson (Lexiscan®) will be recruited to participate in the study. Following regadenoson (administered as part of a stress routine test protocol) participants will receive either aminophylline (75 mg - intravenously) or a matching inactive placebo (sterile salt water) injection. Participants will be surveyed for gastrointestinal symptoms and other side effects related to regadenoson. The frequency and severity of such side effects will be compared between the two study groups (aminophylline vs. placebo).

Inclusion Criteria:

• Adult patients referred to undergo a clinically-indicated regadenoson-stress myocardial perfusion imaging at Rush University Medical Center

Exclusion Criteria:

• Patient refusal to participate
• Known allergic reaction to aminophylline.
• Pre-existing headache or acute/subacute GI illness with symptoms of diarrhea, abdominal discomfort, nausea or vomiting.
• Any contraindication to aminophylline: hypotension, unstable cardiac arrhythmias and acute coronary symptoms.
• Uncontrolled seizure disorder defined as more than 2 seizure episodes in the past 12 months or any seizure in the past week.
• Pregnant or breast-feeding women.
• Patients receiving anti-platelet agent dipyridamole (Persantine® or Aggrenox®).