 Good morning. Today we'll be talking about not very common problem, but it's a problem we face a lot in cardiology. It's called chronic total occlusion of coronary artery. What does that mean? Let's say someone have chest pain. That chest pain caused by a blockage. We do stress test, it's not normal. We do a cardiac cath and we find out that the blockage is 90% or 80% or 70%. And okay, in that case we will go ahead, open it. Usually you put a stint and usually success is close to 99%. However, 28% of the time we find out that the blockage is 100%. It's old, it's not new. It's usually more than three months old and has a lot of calcium on it. Those are very hard blockages to deal with. They're like cement. And we call those chronic, which means old, older than three months, chronic total occlusion. So chronic total occlusion could be handled. Traditionally, most doctors either leave it alone, put patient on bunch of medications. Sometimes they work, sometimes they don't. Some patients keep having symptoms like chest pain or shortness of breath. Fatigue, lack of productivity. Every time they want to do something, their chest hold them back. So those patients we handle by a procedure that approaches the chronic total occlusion. This procedure requires trip to the cat lab. We have to access both groins and we go after the blockage from both ends. The end that starts with it and the other end backward through collateral flow. So those collateral flow are small, tiny vessels from the opposite vessel. Let's say the right vessel is blocked 100%. Well then the left vessel gives the collateral. So we go through the left and go backward through the collateral up the blocked vessel. So we go from the back door in a way. This procedure has really changed the success rate from 10% to over 85%. I have done many patients and the results are fantastic. Patients feel great after we succeed and they go back to regular life. They have to be emplavics and aspirin afterwards for about a year or two. But they are happy with taking that because they feel a whole lot better.