Technique - Overview - Patient selection

Patient selection

Patients with good pulsating radial arteries and with adequate collateral connections with the ulnar artery, are suitable for transradial coronary angioplasty.

General exclusion criteria are:

1. Absence of radial artery pulsation
2. Absent functional collaterals as demonstrated by the Allen's test or by saturation measurements in combination with phlethysmography*
3. Arteriovenous shunt for renal dialysis

*At the OLVG no more tests on presence of collaterals are performed.

Depending on the level of experience, additional relative contraindications are:

1. Small radial artery
2. Acute myocardial infarction
3. Known pathology in the proximal vasculature

Starting physicians should select optimal patients first, in order to become familiar with the technique:

1. Clinically stable
2. Large radial artery with a normal Allen's test
3. Aortic root size and configuration within normal limits
4. Normal take-off of coronary arteries
5. Limited coronary artery disease, easily accessible
6. (Expected) hemodynamic stability during angioplasty
7. No peripheral arterial disease

For the assessment of the diameter of the radial artery, simple palpation is enough. You do not need ultrasound to determine the suitability of a radial artery for 6F cannulation. However, during early experience some ultrasound studies on radial artery diameter will help you to validate your assessment on physical examination.

These contraindications can be deleted from a previous list:

1. Acute myocardial infarction:
At present an experienced operator should be motivated to do emergent procedures also via the radial approach, since most of these patients are heavily anticoagulated.
2. Expected need for intraaortic balloon pumping.
Use of one groin for IABP will reduce risk of bleeding, compared to a situation in which the other groin is used for coronary cannulation.
3. Expected need for venous access (pacing, Swan Ganz).
The use of the radial arteryfor coronary access will still reduce risk of bleeding. Venous femoral access allows right heart catheterization.
4. 6F incompatible techniques
With the release of larger 7F catheters and with introduction of 8F catheters more complex pathology requiring rotablator and other bulky devices can be addressed.
5. LIMA angiography / angioplasty
It is possible to cannulate the LIMA from the right radial artery. Specific curves are underway. The left radial artery is ideal for LIMA cannulation.

Allen's test
	The presence of collaterals between the radial and ulnar arteries is clinically assessed by the Allen test: Under complete compression of both radial and ulnar arteries, the patient is asked to make a fist. The hand becomes pale at opening. A positive Allen test indicating good functioning collaterals is present if, at release of pressure over the ulnar artery, the normal color of the hand returns within 10 seconds. If the hand remains pale, the Allen test is negative.
A more sensitive test to assess the presence of functioning collaterals is plethysmography. The sensor is clipped on the thumb and the radial and ulnar arteries are compressed. The curve will flatten. If at release of pressure over the ulnar artery the plethysmography curve returns, collaterals are present. If the curve does not return immediately, wait an extra minute. You might see that the curve slowly returns, by recruitment of collaterals. If you then repeat the test, the curve comes back more rapidly, which means that there are functioning collaterals. A persistent absence of a curve means that there are no collaterals. In that case that radial artery should not be punctured.