Surgery: light – thermal – and electrical application – Light – thermal – and electrical application – Electrical therapeutic systems
Reexamination Certificate
2000-09-26
2003-09-30
Schaetzle, Kennedy (Department: 3762)
Surgery: light, thermal, and electrical application
Light, thermal, and electrical application
Electrical therapeutic systems
C607S002000
Reexamination Certificate
active
06628987
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to methods and systems for performing a medical procedure, especially procedures during which it is necessary to adjust the beating of the heart. More particularly, this invention relates to methods and systems for sensing imminent cardiac contractions during such a procedure.
BACKGROUND OF THE INVENTION
The current leading cause of death in the United States is coronary artery disease in which the coronary arteries are blocked by atherosclerotic plaques or deposits of fat. The typical treatment to relieve a partially or fully blocked coronary artery is coronary artery bypass graph (CABG) surgery.
CABG surgery, also known as “heart bypass” surgery, generally entails using a graph to bypass the coronary obstruction. The procedure is generally lengthy, traumatic and subject to patient risks. Among the risk factors involved is the use of a cardiopulmonary bypass (CPB) circuit, also known as a “heart-lung machine”, to pump blood and oxygenate the blood so that the patient's heart may be stopped during the surgery.
Conventional CABG procedures are typically conducted on a stopped heart while the patient is on a CPB circuit. A stopped heart and a CPB circuit enables a surgeon to work in a bloodless, still operative field. However, there are a number of problems associated with CABG procedures performed while on CPB including the initiation of a systemic inflammatory response due to interactions of blood elements with the artificial material surfaces of the CPB circuit and global myocardial ischemia due to cardioplegic cardiac arrest. For these reasons, avoiding the use of CPB or cardioplegic cardiac arrest may help minimize post-operative complications.
One method, as disclosed in U.S. Pat. No. 5,651,378 to inventors Matheny and Taylor and in U.S. Pat. No. 5,913,876 to inventors Taylor et al., for facilitating coronary bypass surgery on a beating heart and thereby avoid the use of CPB and cardioplegic cardiac arrest includes stimulating the vagal nerve electrically in order to temporarily stop or substantially reduce the beating of the heart. This may be followed by pacing the heart to start its beating.
Another method, as disclosed in two published PCT applications, WO 99/09971 and WO 99/09973, both to inventor Puskas, involves stopping the beating of the heart during coronary bypass surgery using electrical stimulation of the vagal nerve in combination with administration of drugs. Another method, as disclosed in U.S. Pat. No. 6,060,454 to inventor Duhaylongsod, involves stopping the beating of the heart during coronary bypass surgery via the local delivery of drugs to the heart.
Although it is desirable to stop the heart for a period of time in order to allow the surgeon to accomplish a required task without interference from heart movement, i.e. a motionless operative field, it is undesirable to have the heart stopped for too long a period of time since the body needs, among other things, a constant supply of oxygen. In fact, it is particularly important to maintain sufficient blood flow, and therefore oxygen flow, to the brain. Stopping the heart for prolonged periods of time may cause damage to the patient.
Moreover, once stopped or still, the heart may still contract occasionally. This is sometimes referred to as an “escape beat.” Such an “escape beat” may occur without any warning to the surgeon and the movement associated with the escape beat may interfere with the medical procedure being carried out.
It would be desirable therefore to provide a method for temporarily stopping or slowing the heart in order to control blood flow during a medical procedure.
It would further be desirable to provide a means for sensing an imminent cardiac contraction during the procedure.
It would further be desirable to provide a means for alerting the surgeon of an imminent contraction during the procedure.
SUMMARY OF THE INVENTION
One aspect of the present invention provides a system for performing a medical procedure. The system includes a sensor to sense a state of a cardiac tissue and an indicator to indicate the state of the cardiac tissue.
The system may also include a nerve stimulator in communication with the sensor to inhibit beating of a heart when the state indicated by the indicator is a non-contracting state. The nerve stimulator may stimulate a nerve such as a vagal nerve, a carotid sinus nerve, a fat pad. The nerve stimulator may be, for example, one or more electrodes, such as nerve stimulation electrodes, endotracheal electrodes, endoesophageal electrodes, intravascular electrodes, transcutaneous electrodes, intracutaneous electrodes, balloon-type electrodes, basket-type electrodes, umbrella-type electrodes, tape-type electrodes, suction-type electrodes, screw-type electrodes, barb-type electrodes, bipolar electrodes, monopolar electrodes, metal electrodes, wire electrodes, patch electrodes, cuff electrodes, clip electrodes, needle electrodes and probe electrodes.
The system may also include a cardiac stimulator in communication with the sensor to stimulate beating of a heart when the state indicated by the indicator is a contracting state. The cardiac stimulator may be, for example, one or more electrodes, such as cardiac stimulation electrodes, clip electrodes, needle electrodes, probe electrodes, pacing electrodes, epicardial electrodes, patch electrodes, intravascular electrodes, balloon-type electrodes, basket-type electrodes, tape-type electrodes, umbrella-type electrodes, suction-type electrodes, endotracheal electrodes, endoesophageal electrodes, transcutaneous electrodes, intracutaneous electrodes, screw-type electrodes, barb-type electrodes, bipolar electrodes, monopolar electrodes, metal electrodes, wire electrodes and cuff electrodes.
The sensor may be an electrical sensor, a chemical sensor, an electromagnetic interference sensor, an electrochemical sensor, a pressure sensor, a sound wave sensor, a magnetic sensor, an ultraviolet sensor, a visible light sensor, an infrared sensor, a radiation sensor, a flow sensor, a temperature sensor, a gas sensor, an optical sensor, a pH sensor, a potentiometric sensor, a fluorescence sensor, a depolarization sensor and a biosensor. The sensor may also comprise one or more electrodes, such as cardiac stimulation electrodes, clip electrodes, needle electrodes, probe electrodes, pacing electrodes, epicardial electrodes, patch electrodes, intravascular electrodes, balloon-type electrodes, basket-type electrodes, tape-type electrodes, umbrella-type electrodes, suction-type electrodes, endotracheal electrodes, endoesophageal electrodes, transcutaneous electrodes, intracutaneous electrodes, screw-type electrodes, barb-type electrodes, bipolar electrodes, monopolar electrodes, metal electrodes, wire electrodes and cuff electrodes. The sensor and the cardiac stimulator may be the same.
The system may also include drug delivery means such as a spray, a cream, an ointment, a medicament, a pill, a patch, a catheter, a cannula, a needle and syringe, a pump, and an iontophoretic drug delivery device to deliver at least one drug during the procedure. The drug may be a beta-blocker, a cholinergic agent, a cholinesterase inhibitor, a calcium channel blocker, a sodium channel blocker, a potassium channel agent, adenosine, an adenosine receptor agonist, an adenosine deaminase inhibitor, dipyridamole, a monoamine oxidase inhibitor, digoxin, digitalis, lignocaine, a bradykinin agent, a serotoninergic agonist, an antiarrythmic agent, a cardiac glycoside, a local anesthetic, atropine, a calcium solution, an agent that promotes heart rate, an agent that promotes heart contractions, dopamine, a catecholamine, an inotrope glucagon, a hormone, forskolin, epinephrine, norepinephrine, thyroid hormone, a phosphodiesterase inhibitor, prostacyclin, prostaglandin and a methylxanthine. The drug may be naturally occurring or chemically synthesized.
The system may also include a breathing regulator, which may control a respirator. The breathing regulator may stimulate a phrenic nerve. The breathing regulator m
Hill Michael R. S.
Jahns Scott E.
Keogh James R.
Berry Thomas G.
Droesch Kristen
Latham Daniel W.
Medtronic Inc.
Schaetzle Kennedy
LandOfFree
Method and system for sensing cardiac contractions during... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and system for sensing cardiac contractions during..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and system for sensing cardiac contractions during... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3041194