Chronic total coronary occlusions (CTO) occur in up to one-third of patients undergoing coronary angiography. Indications for opening CTOs include relief of angina, improving left ventricular function, decreasing the need for coronary artery bypass surgery, and improved long-term survival. Newer technology, wire-based and non-wired-based, has improved the ability to cross these previously uncrossable lesions, thereby improving the acute success rates of opening these lesions. Also, the advent of drug-eluting stents has markedly increased the long-term patency of these complex lesions. Therefore, the clinical demand for opening these chronically occluded arteries has increased.