INCLUSION CRITERIA

1.1 UA/NSTEMI patients

Ischemic symptoms suspected to represent a non-ST segment elevation ACS (unstable angina [UA] or non-ST segment elevation myocardial infarction NSTEMI) defined as:

Clinical history consistent with new onset, or a worsening pattern, of characteristic ischemic chest pain occurring at rest or with minimal exercise (lasting longer than 10 minutes) and planned to be managed with an invasive strategy

AND at least one of the following:

1. Electrocardiogram (ECG) changes compatible with new ischemia [ST depression of at least 1mm or transient ST elevation or ST elevation of less than or equal to 1 mm or T wave inversion greater than 2 mm in at least 2 contiguous leads].

   or

2. Patients > 60 years of age with normal ECG are eligible provided there is a high degree of certainty that presenting symptoms are due to myocardial ischemia. Such patients must have documented evidence of previous coronary artery disease (CAD) with at least one of the following:

   • Prior MI requiring hospitalization
   • Prior revascularization procedure (more than 3 months ago)
   • Cardiac catheterization showing significant CAD
   • Positive exercise test
   • Other objective evidence of atherosclerotic vascular disease or
3. Already elevated cardiac enzymes or troponin I or T above the upper limit of normal.

1.2 STEMI patients

1. Presenting with signs or symptoms of acute myocardial infarction lasting at least 20 minutes and planned to be managed with an invasive strategy with intent to perform a percutaneous coronary intervention (PCI) during the index hospitalization.

2. Definite ECG changes compatible with STEMI: persistent ST-elevation (> 2 mm in two contiguous precordial leads or > 1 mm in at least two limb leads), or new left bundle branch block, or Q-wave in 2 contiguous leads

   2) Randomized during index hospitalization for acute coronary syndrome 3) Suitable candidate for either radial or femoral artery PCI 4) Intent to perform same-sitting angiography and PCI. 5) Palpable radial artery with documented normal Allen's test 6) Acceptance by operator to use whichever route is assigned by the randomization process 7) Previous experience of the operator with at least 50 cases of radial artery access within the past year 8) Written informed consent

   EXCLUSION CRITERIA

   1. Age < 18 years
   2. Active bleeding or significant increased risk of bleeding, severe hepatic insufficiency, current peptic ulceration, proliferative diabetic retinopathy.
   3. Uncontrolled hypertension
   4. Cardiogenic shock
   5. Prior CABG surgery with use of more than one internal mammary artery
   6. Documented severe peripheral vascular disease precluding a femoral approach
   7. Participation in any study with an investigational drug or device within the previous 30 days
   8. Medical, geographic or social factors making study participation impractical