Palmar Arch Insufficiency as a Risk Factor for Radial Artery Occlusion After Transradial Catheterization

Study Overview
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Brief Summary
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Transradial access (TRA) is commonly used in different medical fields due to the superficial position of the radial artery and related advantages. Despite its popularity, the incidence and importance of related complications, in particular, radial artery occlusion (RAO) remains unclear. Further, the only known independent predictors of the radial artery occlusion are the periprocedural anticoagulation as well as the catheter size. The effect of a variable arterial anatomy has so far not been evaluated. In this context, most institutions prefer to evaluate the collateral circulation of the hand, i.e., the arterial palmar arch and forearm circulation before TRA. The most commonly employed tests are the modified Allen test (MAT) or the combination of pulse oximetry and plethysmography according to Barbeau.In addition, there are more precise, but still semi-quantitative non-invasive methods for palmar arterial collateral function testing. Despite the wealth of these variably accurate and practical tests, invasive and direct hemodynamic measurement of the arterial forearm circulation and its components is lacking. Thus, the human physiologic circulatory reference at this site has been unknown so far. Further, the need of pre-procedural testing itself can be questioned in light of the reported, widely varying prevalence of RAO (1-38%) or critical ischemia (0-0.09%) after TRA. The present study investigated in a first step the invasively obtained, pressure-derived hemodynamic function, i.e., the physiology of the human arterial palmar arch and forearm collateral circulation and in a second step the clinical consequences of the variable palmar arterial anatomy.

Official Title
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Palmar Arch Insufficiency as a Risk Factor for Radial Artery Occlusion After Transradial Catheterization - a Single-Centre Observational Study

Conditions
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Coronary Artery Disease

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age > 18 years Patient receiving transradial coronary angiography and undergoing evaluation of the palmar arterial arch circulation as a quality control Written informed consent to participate in the follow-up Doppler ultrasound examination Exclusion Criteria: Changed anatomical conditions of the radial artery, e.g. after coronary artery bypass surgery with radial harvest

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Normal modified Allen Test<br>Patients undergoing transradial coronary angiography with a modified Allen-Test ≤ 15 seconds | |
| Abnormal modified Allen Test<br>Patients undergoing transradial coronary angiography with a modified Allen-Test > 15 seconds | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Radial artery occlusion | Frequency of radial artery occlusion after transradial coronary angiography; assessed by Doppler ultrasound measurements | 3 months after transradial coronary angiography | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Palmar arch collateral circulation | Quantitatively measure of the pressure-derived function of the palmar collateral circulation during transradial catheterization. Assessment of the collateral function by setting the invasively obtained blood pressure during external occlusion in relation to the unaffected blood pressure of the radial artery. | Measured during transradial access of the coronary angiography, expected to be 1 minute after local anesthesia and direct after successful punctuation of the radial artery | 
| Radial artery stenosis | Frequency of radial artery stenosis after transradial coronary angiography; assessed by Doppler ultrasound measurements | 3 months after transradial coronary angiography | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Transradial catheterization, Transradial access, Radial artery occlusion, Palmar arch collateral circulation, Collateral flow index