Transmyocardial revascularization: the magic of drilling holes in the heart

Drilling holes in myocardial tissue using high-power lasers has shown to be effective in relieving angina in patients in an end-stage coronary heart disease who do not respond to medication and are unsuitable for standard revascularization techniques. An overview is presented of the interaction of various laser systems with myocardial tissue and the many experimental and clinical studies that have been conducted to elucidate the mechanism of the therapeutic effect of transmyocardial (laser) revascularization (TMR or TMLR). An angina relief of 2 classes with an acceptable mortality (5 - 10 %) and morbidity (20 - 30 %) rate is achieved in the majority of patients. Adverse effects can be minimized by critical patient selection and by a percutaneous approach (PMR). There is no significant difference in the results between the treatment modalities. The acute beneficial effect of TMLR might be attributed to sympathetic denervation. The combined thermal and mechanical injury has shown to provoke an angiogenic response that may be enhanced by adding growth factors. Consequent improvement of the myocardial reperfusion and functionality has been observed but needs further verification with, e.g., high-resolution scintigraphic techniques. Based on the experience in over 7000 patients, TMLR shows to be an effective and safe procedure resulting in a significant improvement in the quality of life for a carefully selected patient group suffering from end-stage coronary disease.