摘要:
A method of selecting laser parameters for performing laser-assisted myocardial revascularization 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 heart, specific heart geometry, pre-existing heart arrhythmia and other factors causing a predisposition to heart arrhythmia. A method for performing laser-assisted transmyocardial revascularization (TMR) and percutaneous transluminal myocardial revascularization (PTMR) using such laser energy with parameters selected to avoid inducing undesired cardiac arrhythmia, the method comprising the steps of generating laser energy having a predetermined non-square wave shape, a predetermined wavelength, a predetermined energy flux and a predetermined power level, and delivering the laser energy in a plurality of pulses, the plurality of pulses having a predetermined pulse frequency and a predetermined pulse width, to selected portions of myocardium to form TMR and PTMR channels without synchronizing delivery of the laser beam with the cardiac cycle.
摘要:
An apparatus for stimulating revascularization of myocardium tissue in the ventricular wall of a human heart is disclosed. The apparatus includes means for moving the distal end of an optical fiber element forwardly through the epicardium of the heart and into the myocardium and emitting relatively low power bursts of laser energy from the distal end to form stimulus injury zones that promote capillary growth and tissue revascularization. Each penetration of the optical fiber element may produce multiple stimulus zones spaced radially from or in line with the axis of the optical fiber element. Apparatus for moving the optical fiber element and controlling the laser emissions in a predetermined manner is also disclosed.
摘要:
A drug delivery apparatus for dispensing a predetermined amount of one or more drugs into a laser created opening in the human body, the apparatus consisting of a laser delivery means such as an optical fiber or fiber bundle, a drug conduit which transfers the one or more drugs, drug solutions or other substances to the distal end of the laser delivery means, and the laser delivery means disposed essentially coaxially with the drug conduit. Laser delivery means is used to create a TMR channel or other opening in the body. Dispensed drug or other substance travels through the drug conduit and emanates from the drug conduit to be delivered into the TMR channel or other laser created opening. Drug is dispensed by manually or automatically activating an electric motor which actuates a piston element. A method of use is also disclosed.
摘要:
A drug delivery apparatus for dispensing predetermined volumes of drug, drug solution or other substances into an opening, such as a TMR channel in the human heart, or other laser treated area within the human body, the apparatus consisting of a bifurcated needle with a laser inlet for guiding a laser delivery means, such as an optical fiber or fiber bundle, to adjacent a surface of the human heart or other body structure for creating an opening, such as a TMR channel, or other laser treated area thereon. A drug inlet is for receiving the drug and transmitting the drug to the TMR channel or other laser treated area. Optionally, a piercing tip and/or suction device assists in positioning the apparatus adjacent the tissue to be treated. Drug is dispensed by manually or automatically actuating a piston or syringe element. A method of use is also disclosed.
摘要:
A drug delivery apparatus for dispensing predetermined volumes of drug, drug solution or other substances into an opening, such as a TMR channel in the human heart, or other laser treated area within the human body, the apparatus consisting of a bifurcated needle with a laser inlet for guiding a laser delivery means, such as an optical fiber or fiber bundle, to adjacent a surface of the human heart or other body structure for creating an opening, such as a TMR channel, or other laser treated area thereon. A drug inlet is for receiving the drug and transmitting the drug to the TMR channel or other laser treated area. Optionally, a piercing tip and/or suction device assists in positioning the apparatus adjacent the tissue to be treated. Drug is dispensed by manually or automatically actuating a piston or syringe element. A method of use is also disclosed.
摘要:
A treatment tool such as a catheter, MIS or other surgical tool apparatus for placement within a heart chamber, organ aperture or other body opening and axial ranging therein, the apparatus particularly adapted for laser-assisted percutaneous transmyocardial revascularization (MTR). At the distal end of the tool is an annular ultrasound transducer with associated structure, positioned to transmit ultrasound signals substantially axially aligned with the axis of the treatment tool to the cardiovascular tissue, the transducer further receiving returning signals from the cardiovascular tissue to be treated. In a preferred embodiment, the transducer comprises a piezoelectric crystal material. The transducer assembly is attached to the distal tip of the tool such that a laser delivery means or other functional device can be extended through the lumen of the tool and the annular ultrasound transducer. In a preferred embodiment, the invention is a modular ultrasound device capable of being detachably attached to a steerable catheter, MIS or other surgical tool apparatus. The system also comprises a signal interface extending from the ultrasound transducer and signal processing component operatively connected to the signal interface for real time determination of at least one boundary surface of cardiovascular tissue relative to one or more positions of the distal tip of the treatment tool. A method of delivering laser energy to tissue is disclosed, the method including the steps of positioning the firing tip of a laser delivery means adjacent the front surface of the tissue, delivering laser energy to the tissue, transmitting ultrasound energy to the tissue, receiving ultrasound signals reflected from at least the rear surface of the tissue, and determining the distance betwveen the firing tip of the laser delivery means and the rear surface of the tissue. In a preferred embodiment, the method includes quantitative determination of the contractility or motion of the beating heart, such that changes in the depth of tissue can be used to control the channel depth or other treatment parameters. Retrolasing can also be achieved by mechanically piercing the tissue to a determined depth based on axial ranging measurements, and retracting the treatment tool while simultaneously delivering laser energy therefrom.
摘要:
The method for combined mechanical/laser myocardial revascularization of a human heart includes: inserting a mechanical piercing device and an elongated flexible lasing apparatus into the chest cavity of a patient; mechanically piercing, micro-tearing or spreading the epicardium of the heart; and then lasing from beneath the epicardium through the myocardium. The apparatus is guided to an area exterior to a ventricle of the patient's heart, and the distal end of the optical fiber apparatus is placed internal to the exterior wall of the heart through an opening which has been created by mechanically piercing, micro-tearing or spreading the epicardium, so that the myocardium and not the epicardium is irradiated with laser energy to allow passage of said optical fiber distal end or said laser energy into the left ventricular cavity without causing a laser irradiation of the epicardium which might be a cause of operative bleeding and for better allowing the sealing of the epicardium after the apparatus is removed.
摘要:
Methods and apparatus of embodiments of the invention are adapted to treat tissue inside a patient's body. Aspects of the invention can be used in a wide variety of applications, but certain embodiments provide minimally invasive alternatives for treating atrial fibrillation by delivering a tissue-damaging agent to selected areas of the heart. One exemplary embodiment of the invention provides a method of treating cardiac arrhythmia. This method includes positioning a distal tissue-contacting portion of a body in surface contact with a tissue surface of cardiac tissue; detecting the surface contact between the tissue-contacting portion and the tissue surface; and thereafter, injecting a tissue-ablating agent into the cardiac tissue through the tissue-contacting portion of the body.
摘要:
Methods and apparatus of embodiments of the invention are adapted to treat tissue inside a patient's body. Aspects of the invention can be used in a wide variety of applications, but certain embodiments provide minimally invasive alternatives for treating atrial fibrillation by delivering a tissue-damaging agent to selected areas of the heart. One exemplary embodiment of the invention provides a method of treating cardiac arrhythmia. This method includes positioning a distal tissue-contacting portion of a body in surface contact with a tissue surface of cardiac tissue; detecting the surface contact between the tissue-contacting portion and the tissue surface; and thereafter, injecting a tissue-ablating agent into the cardiac tissue through the tissue-contacting portion of the body.
摘要:
Methods and apparatus of embodiments of the invention are adapted to treat tissue inside a patient's body. Aspects of the invention can be used in a wide variety of applications, but certain embodiments provide minimally invasive alternatives for treating atrial fibrillation by delivering a tissue-damaging agent to selected areas of the heart. One exemplary embodiment of the invention provides a method of treating cardiac arrhythmia. This method includes positioning a distal tissue-contacting portion of a body in surface contact with a tissue surface of cardiac tissue; detecting the surface contact between the tissue-contacting portion and the tissue surface; and thereafter, injecting a tissue-ablating agent into the cardiac tissue through the tissue-contacting portion of the body.