Contrast echocardiography as an intraoperative method to determine the area of myocardium perfused by transmyocardial laser channels: an experimental study

Transmyocardial laser revascularization (TMLR) of the ischemic myocardium has been recognized as a potentially useful adjunct in the treatment of coronary arterial heart disease. Although there are methods to visualize the induced channels, they have been complex or concerned with long-term patency. The present work was designed as a feasibility study to determine whether contrast echocardiography could provide a simple and rapid method to assist the surgeon in determining the extent of the TMLR-treated area.

Transmyocardial channels were created in five Targhee adult sheep myocardium using a Holmium-YAG laser over the area supplied by the second diagonal branch. A commercially developed echocontrast agent (Optison) was injected into the left atrium.

Passage of the dye through the myocardium was observed by epicardial echocardiography in all the animals.

The current study shows that contrast echocardiography using a newer generation contrast agent capable of enhanced and persistent opacification of left ventricular cavity may serve as an effective tool in delineating intraoperatively the area of myocardium treated with TMLR.