Prevention of Radial Artery Occlusion After Transradial Access Using Nitroglycerin

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.

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.