Prevention of Radial Artery Occlusion After Transradial Access Using Nitroglycerin

Study Overview
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Brief Summary
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The radial approach for a coronary angiography has became popular in several centers because of its simplicity and fewer complications. The radial artery occlusion (RAO) is the main inconvenient and impose a limitation of future use of the radial artery as an access site for catheterization in the future. Several strategies have been used to decrease the incidence of RAO (heparin, patent hemostasis, etc). Nitrates in intra-arterial have been widely studied in prevention of this spasm. Current data show that nitroglycerin intra-arterial at the end of the procedure reduce the incidence of RAO. The hypothesis that use of nitroglycerin at the start of catheterization would have the same effect was not tested.

Detailed Description
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Transradial access (TRA) has been increasingly adopted for diagnostic and interventional cardiovascular procedures in many centers worldwide. This is largely driven by the evidence supporting an unequivocal reduction in access site-related complications associated with TRA compared with transfemoral access, as well as reduction in cost and increased patient comfort. The radial artery occlusion (RAO) is the main inconvenient and impose a limitation of future use of the radial artery as an access site for catheterization in the future. RAO is the most commun complication of transradial access, and its incidence continues to reach up to 12%. Nitrates in intra-arterial have been widely studied in prevention of this spasm. Nitroglycerin binds to the surface of endothelial cells and undergoes two chemical reductions to form nitric oxide (NO). The nitric oxide then moves out of the endothelial cell and into an adjacent smooth muscle cell, where it promotes the formation of cyclic guanosine monophosphate (cGMP), which then promotes muscle relaxation. Current data show that nitroglycerin intra-arterial at the end of the procedure reduce the incidence of radial artery occlusion. A big sheath to artery size ratio could reduce the incidence of RAO, so the main objective of this study is to evaluate whether administration of nitroglycerin at the start of a transradial procedure may preserve the patency of the radial artery; as well, confirm if nitroglycerin administration just before sheet removal helps to keep the radial artery patency.

Official Title
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Prevention of Radial Artery Occlusion After Transradial Access Using Nitroglycerin

Conditions
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Injury of Radial Artery

Intervention / Treatment
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* Drug: Nitroglycerin I
* Drug: Placebo I
* Drug: Nitroglycerin II
* Drug: Placebo II


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Indication for cardiac catheterization; Suitable candidates for transradial approach; Use of 5 or 6 French sheath in the procedure; Signed informed consent. Exclusion Criteria: Unable to tolerate nitrates or known allergy to nitrates; Use of any nitrate, by any route of administration, up to 1 hour before the procedure; ST-segment elevation acute myocardial infarction patients during the first 12 hours of sympton onset; Intubated patients (on mechanical ventilation); Complications before or during procedure (cardiac arrest, pulmonary edema, cardiogenic shock, stroke); Prior inclusion in this trial.

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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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Placebo I/Placebo II<br>0,9% Saline 10 mL was given intra-arterially through the sheath at the start of a transradial procedure (right after sheath placement) and 0,9% Saline 10 mL was given intra-arterially through the sheath at the end of procedure (just before sheath removal). | Drug: Placebo I<br>* Saline 0,9% intra-arterially administered through the radial sheath, right after sheath placement and before catheterization.<br>* Other names: Saline;Drug: Placebo II<br>* Saline 0,9% intra-arterially administered through the radial sheath, just before sheath removal and before hemostasis.<br>* Other names: Saline;|
| Experimental: Nitroglycerin I/Placebo II<br>500 microgram of Nitroglycerin (in 10 mL saline) was given intra-arterially through the sheath at the start of a transradial procedure (right after sheath placement) and 0,9% Saline 10 mL was given intra-arterially through the sheath at the end of procedure (just before sheath removal). | Drug: Nitroglycerin I<br>* 500 microgram of Nitroglycerin intra-arterially administered through the radial sheath, right after sheath placement and before catheterization.<br>* Other names: Tridil;Drug: Placebo II<br>* Saline 0,9% intra-arterially administered through the radial sheath, just before sheath removal and before hemostasis.<br>* Other names: Saline;|
| Active Comparator: Placebo I /Nitroglycerin II<br>0,9% Saline 10 mL was given intra-arterially through the sheath at the start of a transradial procedure (right after sheath placement) and 500 microgram of Nitroglycerin (in 10 mL saline) was given intra-arterially through the sheath at the end of procedure (just before sheath removal). | Drug: Placebo I<br>* Saline 0,9% intra-arterially administered through the radial sheath, right after sheath placement and before catheterization.<br>* Other names: Saline;Drug: Nitroglycerin II<br>* 500 microgram of Nitroglycerin intra-arterially administered through the radial sheath, just before sheath removal and before hemostasis.<br>* Other names: Tridil;|
| Experimental: Nitroglycerin I /Nitroglycerin II<br>500 microgram of Nitroglycerin (in 10 mL saline) was given intra-arterially through the sheath at the start of a transradial procedure (right after sheath placement) and 500 microgram of Nitroglycerin (in 10 mL saline) was given intra-arterially through the sheath at the end of procedure (just before sheath removal). | Drug: Nitroglycerin I<br>* 500 microgram of Nitroglycerin intra-arterially administered through the radial sheath, right after sheath placement and before catheterization.<br>* Other names: Tridil;Drug: Nitroglycerin II<br>* 500 microgram of Nitroglycerin intra-arterially administered through the radial sheath, just before sheath removal and before hemostasis.<br>* Other names: Tridil;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Radial artery occlusion | Incidence of radial artery occlusion as confirmed by absence of antegrade flow in vascular doppler ultrasound | 2 to 24 hours after procedure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Late radial artery occlusion | Incidence of radial artery occlusion as confirmed by absence of antegrade flow in vascular doppler ultrasound | 30 days after procedure | 
| Pain assessment | Pain felt by the patient in the forearm, assessed using numeric pain rating scale | up to 24 hours after procedure | 
| Spasm (operator evaluation) | Catheter friction, as experienced by the operator (subjective measure) | Immediate | 
| Procedure duration | Total duration of the procedure, from puncture to haemostatic dressing. | Immediate | 
| Radiation exposure | Total radiation used in the procedure | Immediate |