Regadenoson and Adenosine

Comparison of Regadenoson (Rapiscan) and Central Intravenous Adenosine for Measurement of Fractional Flow Reserve

The aim of the study is to test the accuracy of Regadenoson to induce maximal and steady state hyperemia as compared to central venous infusion of adenosine for assessing fractional flow reserve. (adenosine is considered to be the gold standard)and to investigate the time intervals of maximum hyperemia induced by centrally and peripherally administered Regadenoson.

Inclusion Criteria:

• Age 18-80 years
• Scheduled for invasive measurement of FFR for diagnostic and interventional purposes in proximal or mid segments of a coronary artery

Exclusion Criteria:

• Severe aortic valve stenosis
• History of severe COPD
• Syncope or bradycardia (less than 50 beats/min)
• Known conduction disturbances (2nd-3rd degree heart-block, sick sinus without pacemaker or long QT-syndrome)
• Severe hypotension (RR <90 mmHg)
• Patients in whom no access to the coronary circulation can be obtained by the femoral artery or in whom femoral access was problematic
• Coronary anatomy not suitable for FFR measurement (extremely tortuous or calcified coronary vessels)
• Previous coronary bypass surgery
• Recent ST elevation myocardial infarction (<5 days)
• Recent non-ST elevation myocardial infarction (<5 days) if the peak CK is >1000 IU
• Inability to provide informed consent
• Pregnancy
• Use of methylxanthines (in the last 12 hours)
• Use of Dipyridamol (in the last 48 hours)