Stenting in unprotected left main coronary stenosis-"What no progress"?

There does not appear to be a difference in patient outcomes of percutaneous coronary intervention for unprotected left main coronary artery stenosis whether using first- or second-generation drug elutting stent. This is despite increase in patients having more adjunctive procedures such as intravascular imaging and newer generation antiplatelet agents. This single-center study provokes questions as to why there has not been improvement in outcomes.