Low-molecular-weight heparin in radial artery occlusion treatment: the LOW-RAO randomized study.

Radial artery occlusion (RAO) is the commonest complication of transradial catheterization. There is no evidence-based therapy, in the frame of a randomized control study, for the treatment of RAO. The purpose of the LOW-RAO study is to question the hypothesis if low-molecular-weight heparin is effective in the treatment of RAO after transradial coronary catheterization (both angiography and percutaneous coronary intervention). It is a prospective, open label, randomized controlled trial that will randomize 60 patients with RAO, irrespective of symptoms, into two groups, one receiving anticoagulation with low-molecular-weight heparin and the other receiving no treatment. The primary end point is improvement in radial artery patency rate at 4 weeks after the procedure. Clinical trial registration number: NCT04196309 (ClinicalTrials.gov).

Lay abstract Coronary angiogram, a procedure to check if there is any blockage in the heart's blood vessels, is often performed nowadays through a vessel in the wrist, called radial artery. One of the commonest risks of this procedure is the blockage of the radial artery afterward. This could go totally unnoticed; however, it may cause pain, tingling and numbness feeling in the fingers, loss of handgrip power and inability to use the artery for medical reasons in the future. Since there is no definite treatment for this situation up to now, the purpose of the LOW-RAO study is to try to find a solution for this problem. Patients diagnosed with radial artery blockage, will randomly receive for up to 4 weeks an injection that contains a blood-thinner, called low-molecular-weight heparin and is believed to be able to reopen the blocked radial artery. All patients will be regularly followed-up with ultrasounds for a month to check any progress with the blockage.