摘要:
Disclosed is a completely implantable system that can detect the occurrence of a myocardial infarction, i.e., a heart attack, and automatically inject a thrombolytic and/or anti-thrombogenic agent into the bloodstream to promptly dissolve the thrombus that caused the myocardial infarction and prevent the formation of additional thrombi. It is well known that a myocardial infarction can be detected from a patient's electrocardiogram by noting an ST segment voltage deviation. Upon detection of a myocardial infarction, an ST segment deviation electronic detection circuit within the implanted device can produce an output signal that can cause a thrombolytic and/or anti-thrombogenic agent contained within an implanted, pressurized reservoir to immediately and automatically release medications into the patient's bloodstream. A patient warning system is also provided by an audio alarm or an electrical tickle within the human body indicating that a myocardial infarction has been detected. An externally located part of the system, in the form of a patient operated initiator, can be used to trigger the release of medication as soon as a first sign of a stroke has been detected in order to prevent damage to brain tissue that would be caused by that stroke. Thus the system can be used to prevent trissue damage from either a myocardial infarction or a stroke. The implanted system can also send a radio message to an externally located receiver that automatically dials an emergency rescue team to take the patient to a hospital for continuing treatment of a myocardial infarction or a stroke.
摘要:
Disclosed is a system for detecting a myocardial infarction (i.e., a heart attack) at the earliest possible time and promptly warning the patient that he should immediately seek medical care. Specifically, a first embodiment of the present invention has an implantable electronic system that can sense a change in the patient's electrogram that is indicative of a myocardial infarction. If a myocardial infarction is sensed, the device would then cause an implantable or externally located alarm means such as an audio sound to be actuated to warn the patient of his condition. The patient could then promptly seek medical care, for example, at a hospital emergency room. Having been trained to recognize such an alarm, most patient would neither fail to recognize such an indication of a myocardial infarction nor would they ignore such an alarm signal if it were to occur. Since an implantable heart pacemaker or defibrillator already has within its structure many of the elements required for the device to recognize a myocardial infarction, it would be expeditious to add a capability to these existing devices to detect a myocardial infarction and provide an implantable or external alarm means to inform the patient to take appropriate action.
摘要:
Disclosed is a balloon on a distal portion of a balloon angioplasty catheter. The section of the balloon onto which a stent can be mounted has a central segment that is substantially cylindrical in shape that is centered between two segments each having the shape of a sector of a prolate spheroid. This shape for a balloon for a stent delivery catheter provides a more cylindrical shape for the stent after it is implanted in an artery that has a typical distribution of plaque in an arterial stenosis, which distribution of plaque is greatest for some limited length at a central region of the stenosis and then decreases somewhat uniformly as one approaches the edges of the stenosis. Another embodiment of the invention utilizes two segments that are frustums of a cone instead of sectors of a prolate spheroid, which conical segments surround the central cylindrical segment. Also disclosed is a balloon whose compliance decreases continuously as a function of the distance away from either end of the central segment. Any of these embodiments can employ dual conical end segments at each end of the balloon which consist of two adjacent frustums of a cone making different half-angles with the longitudinal axis of the balloon.
摘要:
The present invention is an injection port assembly for subcutaneous delivery of medication. A single molded body has a soft cannula extending downward from a generally flat bottom surface and a self-sealing septum mounted at the center of a top surface which is generally of a concave shape sloping downward towards its outer perimeter at which point the single body is very thin. The single body also has a tubular extension which is directed outward parallel to the skin's surface. A metal needle which penetrates through the septum and through the lumen of the soft cannula is used for inserting the cannula through the skin. Once the soft cannula is placed subcutaneously, the needle is removed and an adhesive tape is placed over the single body and onto the skin beyond the body's outer perimeter. By having a distal section of the needle which is smaller in diameter as compared to most of the needle's length, and by having the soft cannula fit tightly onto the needle, most of the cannula's length will be in tension during insertion thereby preventing an accordion-like compressional failure of the cannula. A quick-release connector on the proximal end of the tubular extension or mounted directly on the injection port assembly allows the tubing connecting the injection port assembly to a portable medication pump to be disconnected when the patient showers or performs some similar activity.
摘要:
Disclosed is a system for the detection of cardiac events (a guardian system) that includes an implanted device called a cardiosaver, a physician's programmer and an external alarm system. The system is designed to provide early detection of cardiac events such as acute myocardial infarction or exercise induced myocardial ischemia caused by an increased heart rate or exertion. The system can also alert the patient with a less urgent alarm if a heart arrhythmia is detected. Using one or more detection algorithms, the cardiosaver can detect a change in the patient's electrogram that is indicative of a cardiac event within five minutes after it occurs and then automatically warn the patient that the event is occurring. To provide this warning, the guardian system includes an internal alarm sub-system (internal alarm means) within the cardiosaver and/or an external alarm system (external alarm means). If the guardian system is put into a pacemaker, the algorithm can utilize a different analysis of the electrogram depending on whether or not the pacemaker is actually pacing the heart.
摘要:
Disclosed is a system for the detection of cardiac events (a guardian system) that includes an implanted device called a cardiosaver, a physician's programmer and an external alarm system. The system is designed to provide early detection of cardiac events such as acute myocardial infarction or exercise induced myocardial ischemia caused by an increased heart rate or exertion. The system can also alert the patient with a less urgent alarm if a heart arrhythmia is detected. Using one or more detection algorithms, the cardiosaver can detect a change in the patient's electrogram that is indicative of a cardiac event within five minutes after it occurs and then automatically warn the patient that the event is occurring. To provide this warning, the guardian system includes an internal alarm sub-system (internal alarm means) within the cardiosaver and/or an external alarm system (external alarm means). If the guardian system is put into a pacemaker, the algorithm can utilize a different analysis of the electrogram depending on whether or not the pacemaker is actually pacing the heart.
摘要:
A hybrid stent that is defined as having a central section that is balloon expandable and end sections that are self-expanding. The entire stent is mounted on a balloon of a balloon angioplasty catheter. One way to retain the self-expanding portion of the stent onto a balloon onto which it has been nested is to place a cylindrical elastomer tube around each of the self-expanding end sections of the stent. Another way to retain the hybrid stent onto a stent delivery system is to use a conventional sheath that is pulled back to initiate stent deployment
摘要:
The present invention is a stent delivery system that uses a short section of a guide wire that is fixedly attached to a distal section of a balloon angioplasty catheter. By not having a guide wire that slides through the balloon of the balloon angioplasty catheter, the balloon on which the stent is mounted can have a reduced diameter. Therefore, the outside diameter of the undeployed stent mounted onto that balloon is also minimized. This provides a minimum profile, i.e., a minimum outside diameter, for the stent. A minimum profile at the distal section of the stent delivery system is highly advantageous for improving the percentage of cases that can be treated by means of direct stenting; i.e., without requiring pre-dilation of a stenosis.
摘要:
An expandable stent for delivery to a coronary artery. The stent has at least two longitudinally spaced apart circumferential rings having closed ends. Each of the circumferential rings has at least two peak segments and at least two valley segments. At least one longitudinally extending connector extends between adjacent circumferential rings. The connector has a first end portion fixedly connected to a first circumferential ring and a second end portion fixedly connected to an adjacent circumferential ring. The connector has at least one circumferentially extending turn back portion between its first and second end portions that can expand or contract in length while being passed through a curved coronary artery.
摘要:
The present invention is a hybrid stent that is defined as having a central section that is balloon expandable and end sections that are self-expanding. The entire stent is mounted on a balloon of a balloon angioplasty catheter. One way to retain the self-expanding portion of the stent onto a balloon onto which it has been nested is to place a cylindrical elastomer tube around each of the self-expanding end sections of the stent. Another way to retain the hybrid stent onto a stent delivery system is to use a conventional sheath that is pulled back to initiate stent deployment