Stents are great for things like increasing blood flow and reducing the risk of heart attacks, but a new study says they’re not great for what they’re mainly used for—treating chest pain. Researchers split a cohort of 230 UK patients experiencing chest pain into two groups: one received coronary stents, one got a placebo procedure. Six weeks later, they found no difference in experienced chest pains between the two groups. Again, chest pain isn’t the only medical use for stents, and this study only had patients with a single blocked artery. But since 500,000 patients worldwide receive stents for chest pain relief every year, cardiologists might soon be spending less time optimizing patient blood flows, and more time playing old school oil flow games.