II. Definition
- Myocardial Perfusion Imaging using Adenosine (or Regadenoson/Lexiscan)
III. Approach
- Hold nitrates (Nitroglycerin) on day of the test
- Hold methylzanthines 24 hours before test
- Theodur
- Aminophylline
- Dipyridamole
IV. Preparations
V. Advantages
- Short duration of Adenosine action (<3 seconds)
- Vasodilator increases coronary flow 5x
- More sensitive than Dobutamine (but less specific)
- ST Depression specific for serious disease
- Left main Coronary Artery Disease
- Three-vessel Coronary Artery Disease
VI. Indications
- Left Bundle Branch Block
- Paced Rhythm
- WPW Syndrome
VII. Contraindications
- Asthma
- Severe Chronic Obstructive Pulmonary Disease (COPD)
- Concurrent medication use
- Dipyridamole
- Aggrenox
- Theophylline
- Caffeine prior to test (e.g. Coffee, Chocolate)