Direct myocardial revascularization (DMR), either surgical or catheter-based, uses lasers to create channels between ischemic myocardium and the left ventricular cavity to improve perfusion and decrease angina. This technique can also be used to deliver drugs to the damaged tissue. Candidates include patients with chronic, severe, refractory angina and those unable to undergo conventional surgical revascularization or angioplasty because remaining conduits or acceptable target vessels are lacking. Although the mechanism of action of DMR is still not known, several theories have been proposed, including stimulated angiogenesis. Late sequelae also remain to be determined. Channel characteristics differ depending on whether they were created by carbon dioxide or holmium/yttrium-aluminum-garnet (Ho: YAG) lasers. Catheter-based DMR obviates thoracotomy and anesthesia and, in systems that can create electromechanical maps, fluoroscopy. Phase I clinical trials are now under way to evaluate catheter-based DMR, with endpoints that include improvement in symptoms of angina, exercise capacity, and radionuclide myocardial perfusion.