Transmyocardial Laser Revascularization
Transmyocardial laser revascularization is a surgical technique that attempts to improve the blood supply to ischemic myocardium by using a high-powered laser to create multiple minute (1mm) channels, which traverse the heart muscle (transmyocardial). One theory is that these new channels may bring blood from the ventricular cavity directly into the myocardium. The result would therefore be that the heart functions more like a reptilian heart, in which a significant portion of the heart's blood supply comes directly from the left ventricular cavity (sinusoidal blood flow). Another theory is that these channels trigger the in growth of tiny blood vessels into the area treated (angiogenesis).
These transmyocardial channels are placed in the area of myocardium at risk (ischemic) approximately one cm apart, so that there is multiple channel perfusion of ischemic area or areas. For the procedure, the patient is given general anesthesia but in many cases the patient may not be placed on the heart lung machine.
This technique is generally reserved for patients who have "end-stage coronary artery disease" that cannot be corrected by the usual means. Meaning that there is either poor runoff or no place to perform a conventional revascularization either by coronary artery bypass or interventional techniques by the cardiologist, such as angioplasty or stenting.
In all cases patients should have a radioactive perfusion scan which shows evidence of reversible ischemia. That is, there should be areas of myocardium that are ischemic (lacking sufficient blood supply) but not infarcted (dead). The patients should have reasonable heart wall function, with left ventricular ejection fractions above 0.20%. Patients should have very severe disabling angina and should be on maximal medical therapy.