Abstract: A method of and apparatus for performing a transmyocardial revascularization procedure is disclosed which utilizes two laser power sources. A first laser source provides a coagulating or blanching effect on tissue and a second laser source capable of tissue ablation are supplied to a combined optical fiber bundle comprising a plurality of fibers which can be moved axially or rotatively by the operating physician. As the distal end of the fiber bundle is moved forward, bursts of laser energy therefrom may be programmed to first penetrate the epicardium with minimal bleeding and thereafter provide channels or pockets in the myocardium for causing or stimulating angiogenesis.
Abstract: A method of selecting laser parameters for performing laser-assisted transmyocardial revascularization (TMR) to avoid inducing undesired cardiac arrhythmia without synchronization of delivery of laser energy and the patient's cardiac cycle, the method comprising the steps of minimizing the power level of laser energy used, thereby decreasing the overall trauma to the heart, selecting a pulse frequency as great as possible while avoiding adverse summation effects, selecting a pulse width as wide as possible to prevent excessively high peak powers per pulse and not so wide as to cause undesired thermal damage, selecting an energy flux rate, shaping the front end of each pulse of laser energy to provide efficient, non explosive TMR channeling, and correcting the selected power level, pulse width, pulse frequency and energy flux rate for mechanical events, including method of access to the heart, position of selected portions of myocardium in the heart, temporal duration of the procedure, natural movement of the
Type:
Grant
Filed:
October 15, 1996
Date of Patent:
July 28, 1998
Assignee:
Eclipse Surgical Technologies, Inc.
Inventors:
Douglas R. Murphy-Chutorian, Stuart D. Harman
Abstract: A minimally invasive surgical apparatus for providing access to the inside of a chamber of the heart for performing TMR on anterior and posterior walls therein. A unitary or a two piece trocar assembly is positioned through the chest wall. An obturator with a tissue piercing blade at one end is used to saw, pierce or otherwise cut a hole through the epicardium into and through myocardium. Once the trocar assembly extends into the heart chamber, a laser delivery device with deflection means is introduced into the chamber. Deflection or curvature of the end of the laser delivery device can be controlled by angulation control components, such that TMR channels can be created at various positions on the anterior and posterior walls of the chamber. Rotation control components for the fiber or other laser delivery devices will allow the surgeon to rotate the fiber once a predetermined deflection or curvature has been imparted to the distal end of the laser delivery device.