Grant: Project Grant

Patients suffering a heart attack undergo a life-saving procedure called angioplasty, by which the blockage in the artery that caused the heart attack is opened and a stent is placed. In about half of the patients, additional blockages are found in other arteries. These are incidental findings and doctors have debated for years whether they should be treated with angioplasty or medications. We recently answered this question in a large multinational study called the COMPLETE trial. We showed that opening additional blockages reduced patient deaths or repeating heart attacks. A major concern is that not all of these angioplasties are necessary, but doctors do not know which arteries should be opened and which should be left alone. In the COMPLETE trial, the severity of blockages was estimated by visual inspection which is not a reliable method. Recently, new technique involving a special wire was proposed. It measures the blood pressure before and after a narrowing to estimate its severity. The advantage of this method is it can reduce the number of angioplasties by opening only the most important blockages thereby improving safety and costs. The main problem with using this method today is that doctors do not know of it. We are proposing a first large-scale trial to address this important issue. COMPLETE-2 trial will enroll 5100 patients at 140 sites worldwide. We aim to test whether the use of a pressure wire is as good as visually estimating the degree of narrowing when deciding which additional blockages found during the heart attack need to be treated with stents. We will test the usefulness of both methods and if it will improve patient safety by reducing unnecessary procedures, thereby decreasing bleeding, strokes and kidney injury. This study question is important in Canada because we have an unique health care system and the collaboration of doctors across the country will allow for efficient performance of randomized trials of heart attack patients.