ACTION-1 is a unique international study into the use of blood thinners (heparin) in open aortic surgery (for abdominal aortic aneurysm, AAA). For the first time in the world, the best method for thinning blood during vascular surgery will be researched in more than 20 hospitals in the Netherlands and Germany. The optimal dose of heparin needed to prevent troublesome blood clots is not yet known. In most cases, a standard single dose of 5,000 units is given. The effectiveness of heparin can be measured by a simple test that indicates the rate blood clots form. This is called the Activated Clotting Time, or ACT. Up until now, this test was not standard procedure in open aneurysm repair surgery. The ACTION-1 study will find the optimal dose of heparin in order to reduce the chances of patients suffering serious complications.

This research was initiated by the department of surgery at Dijklander Hospital in Hoorn, in collaboration with Amsterdam University Medical Centres, locations AMC and VUmc. The study has been made possible by a grant from ZonMw (848043004) and Medtronic®. The study is approved by the Medical Ethics Committee of Amsterdam UMC, location VUmc, and meets all the legal criteria. The study is also supported by the NVvH (Dutch Society of Surgeons), NVvV (Dutch Society of Vascular Surgeons), Federation of Medical Specialists, and the patient association Harteraad.