Optimal Delay Time to Initiate Anticoagulation after Ischemic Stroke in Atrial Fibrillation

Study Synopsis

START will determine the best time to initiate blood-thinning treatment in patients after they have had a stroke in the setting of Atrial Fibrillation, the most common heart arrhythmia in the United States and one which increases the risk of stroke.

After an ischemic stroke has occurred in a patient with a clot-forming condition such as Atrial Fibrillation, it is typically standard for the patient to be prescribed anticoagulants or blood-thinning medications. Although this is the standard treatment, is it not known when to initiate treatment. Starting anticoagulation too soon may cause a patient’s stroke to actually bleed, while waiting too long may cause another clot to form and cause another stroke. Current AHA guidelines suggest starting treatment between 2-14 days after the stroke has occurred.

Previous research to answer this question has been retrospective and has suggested that a large, prospective, randomized trial was needed. START is the first study of its kind in the United States to randomize when these patients should begin their treatment and compare the different groups’ rates of having recurrent strokes or bleeding events 30 days out from their stroke. Interim analyses will take place after every 100 patients are enrolled, and based on the rates in each group, the probability a future patient may be randomized to a given group will be altered to favor randomization to the time groups that have fewer bleed/stroke events happening to patients in that group.

Research Update

START began recruitment June 15, 2017, at Dell Medical School’s four Seton-affiliated hospitals in the Austin area. Since then, we have initiated the study at nine other comprehensive stroke centers across Texas through the Lone Star Stroke Consortium.

As of May 8, 2023, 200 patients have been enrolled in START and recruitment goal has been accomplished.