Embodiments of the present invention relate to devices and methods for monitoring vascular health conditions, e.g. restenosis and/or thrombosis. Embodiments of the present invention particularly relate to sensor arrangements in support structures configure for implantation, e.g. stents, and/or to communication techniques of sensor arrangements utilized in such support structures. Specifically, they relate to medical devices configured for monitoring one or more health conditions, particularly restenosis, and to methods of monitoring a health condition, particularly restenosis.
The word “atherosclerosis” comes from the Greek words “athero” and “sclerosis”, meaning gruel or paste and hardness, respectively. As it is inferred from the name, it is a disease in which atheromatous plaque, consisting of fatty substances (i.e. cholesterol), platelets, cellular waste products, and calcium build up in the innermost layer of an artery called endothelium. The disease is typically asymptomatic, chronic, slowly progressive, cumulative, and eventually leads to plaque ruptures and therefore clots inside the artery lumen cover the ruptures. The clots heal and usually shrink but leave behind stenosis (narrowing) or in worst case scenario complete occlusion of the artery.
Atherosclerotic disease may occur anywhere throughout vascular system. For example, coronary heart disease (CHD) that is the most common type of heart disease takes about 500,000 lives in the United States every year. In practice, coronary atherosclerotic disease (CAD) is treated by interventional radiologists or cardiologists through medication, non-invasive, or invasive procedures. The choice of physical treatment approach depends on severity of extended disease, which could lead to minimally invasive (e.g. angioplasty, stent implantation), or invasive (e.g. bypass, heart transplantation) surgical procedures.
Atherosclerosis could occur in peripheral arteries that supply blood from heart to head, arms, legs, kidneys and stomach. Similar to CAD, a minimal invasive procedure could be performed to open up the blockage through angioplasty or stent implantation. Another disease that is also correlated with atherosclerosis is abdominal aortic aneurysm (AAA) that is enlargement of abdominal aorta for more than 50% of its original diameter. AAA is the 13th leading cause of death in the US and about 15000 Americans die each year. It is also a chronic disease and when it ruptures only 10-25% of patients survive leaving 75-90% fatality. Likewise CAD and peripheral atherosclerotic disease (PAD), the AAA is stabilized through stent implantation procedure too, known as endovascular aortic (aneurysm) repair (EVAR).
For many years, the ultimate goal of an interventional cardiologist was to physically expand narrowed artery, using balloon and stent, or create additional blood supply connections through bypass surgery. With refinement of new intravascular imaging modalities, today, primary responsibility of an interventional cardiologist is not only to open up the site of occlusion but also to properly cure the atherosclerosis. For example, the United States food and drug administration (FDA) safety panel has suggested that cardiologists take more measures to reduce risks associated with the stents due to troubling headlines about potentially deadly clotting risks in small percentage of them. So far, researchers have mainly focused on the stents themselves and how they are made. But now, attention is turning more toward the way they are being used. There has been a consensus that widespread use of drug—coated stents may increase the risk of deadly clots formation, which has called attentions in the United States and widely reported in the media (Fox News report, Oct. 9, 2008—The New York Times, Feb. 13, 2007—The Wall Street Journal, May 7, 2007—The Boston Globe, Dec. 26, 2004) and in many scientific journals. The medicine on the stent is released gradually over time to stop the progression of the scar tissue. However, the artery can become narrow again, which is known as restenosis. Currently, there is no systematic approach to monitor the progression of atherosclerosis or any abnormality like thrombosis within implanted stent and early detection of restenosis or possible myocardial infarction.
In view of the above, it is an object of the present invention to provide a devices and methods for monitoring restenosis and/or thrombosis and related disease that overcome at least some of the problems in the art.
In light of the above, a device according to independent claims 1 and 3, and a method according to independent claim 11 are provided. Further aspects, advantages, and features of the present invention are apparent from the dependent claims, the description, and the accompanying drawings.
According to one embodiment a device or assembly configured for monitoring one or more health conditions, particularly restenosis, is provided. The device or assembly includes: two or more sensors configured to be implanted for exposure to blood within a vessel or to blood within a graft provided, e.g. implanted, in a vessel, wherein each of the two or more sensors is configured to sense at least the pressure in the vessel or the graft, a support structure for supporting the two or more sensors, wherein the support structure has a distal end and a proximal end, wherein at least one of the two or more sensors is closer to the distal end than another one of the two or more sensors.
According to another embodiment, a device or assembly configured for monitoring one or more health conditions, particularly restenosis, is provided. The device includes one or more sensors configured to be implanted in a vascular, wherein the one or more sensors are configured to sense at least pressure values, a support structure for supporting the one or more sensors, and an a remote device for wirelessly providing energy to the one or more sensors and for reading the pressure values.
According to another embodiment, a device or assembly configured for monitoring one or more health conditions, particularly restenosis, is provided. The device includes one or more electronic chips integrated with sensors configured to be implanted in a vascular, wherein the one or more electronic chips are configured to transmit one or more sensed indices wirelessly, e.g. at least pressure values, a support structure for supporting the one or more sensors and chips, and an a remote device for wirelessly providing energy to the one or more sensors and for reading the pressure values.
According to a further embodiment, a method of monitoring a health condition, particularly restenosis, is provided. The method includes: wirelessly energizing at least one sensor, which senses at least vascular pressure values, with a remote device, reading at least the pressure values for a predetermined time period via a wireless data transfer from the at least one sensor, communicating the pressure values to a computer system, and receiving information related to the health condition from the computer system.
According to one embodiment a device or assembly configured for monitoring one or more health conditions, particularly restenosis, is provided. The device or assembly includes: two or more sensors configured to be implanted for exposure to blood within a vessel or to blood within a graft provided, e.g. implanted, in a vessel, wherein each of the two or more sensors is configured to sense at least the pressure in the vessel or the graft, a support structure having two or more rings configured to be implanted in a vessel and for supporting the two or more sensors, wherein the support structure has a distal end and a proximal end, wherein at least one of the two or more sensors is arranged at a first ring of the two or more rings, which is closer to the distal end than a second ring of the two or more rings, wherein at least another sensor of the two or more sensors is attached to the second ring, and a remote device for wirelessly providing energy to the one or more sensors and for reading the pressure values and a reading device configured for wireless communication with the two or more sensors and comprising a port for wired or wireless communication with a computer system, wherein the computer system is a system selected from the group consisting of: a personal computer, a portable computer, a smartphone, a server, a cloud computer system, and combinations thereof.
Embodiments are also directed at apparatuses for carrying out the disclosed methods and include apparatus parts for performing each described method step. These method steps may be performed by way of hardware components, a computer programmed by appropriate software, by any combination of the two or in any other manner. Furthermore, embodiments according to the invention are also directed at methods by which the described apparatus operates. It includes method steps for carrying out every function of the apparatus.
So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments. The accompanying drawings relate to embodiments of the invention and are described in the following:
Reference will now be made in detail to the various embodiments of the invention, one or more examples of which are illustrated in the figures. Within the following description of the drawings, the same reference numbers refer to same components. Generally, only the differences with respect to individual embodiments are described. Each example is provided by way of explanation of the invention and is not meant as a limitation of the invention. Further, features illustrated or described as part of one embodiment can be used on or in conjunction with other embodiments to yield yet a further embodiment. It is intended that the description includes such modifications and variations.
According to embodiments described herein, an intelligent implantable health sensing system is provided. The health sensing system can thereby, include one chip such as a RFID chip, or typically two or multiple RFID chips within support structure's length, e.g. stent's length, to measure and record spatially relative pressure differences. The one or more RFID chips may be integrated with a sensor. Measuring pressure differences helps to monitor any abnormality (restenosis, hemorrhage) systematically for early detection of restenosis and/or failure of a stent. Further, development of disease- and patient-specific cardiac models for early detection of myocardial infarction can be based upon embodiments described herein.
According to yet further embodiments, which can be combined with other embodiments described herein, at least one of the two or more sensors is mounted to the support structure adjacent to the distal end, and wherein the another one of the two or more sensors is mounted to the support structure adjacent to the proximal end. The sensors can be employed as radiofrequency coils in magnetic resonance (MR) imaging systems. The sensors and/or chips, which may be further integrated with further structures can be used as MRI coupling coils (passive coupling through a LC circuit tuned to the MRI lamor frequency) for intravascular imaging. This can provide imaging information about a stenosis grade and also about the structure of the plaque.
The health sensing system is supported with a user-interaction device, e.g. a remote device. According to typical embodiments, which can be combined with other embodiments described herein, the user-interaction device can be a computer or a mobile device, e.g. a smartphone and can optionally, be provided with back-end architecture for secure communication and recording of data and online/offline disease-, patient-, or patient-flow-modeling.
Embodiments described herein can provide a device in which senses the progression of restenosis and/or hemorrhage within the implanted stent upon user's request and sends this information to an external near-body device (e.g. a smartphone). The data can, for example, then transferred to a centralized database for online processing and decision-making. According to some embodiments, which can be combined with other embodiments described herein, two or multiple chips (sensors) are designed along with a stent to collect pressure indices and/or temperature indices, flow rate indices, and/or possible biomarkers.
According to some embodiments, two (or multiple) pressure sensors are designed on stent or another support structure and the pressure indices will be fetched through an external near-body device, such as a remote device including a reading device. The data is transferred to a centralized data station for online analysis and eventually a report is created. In case of life threatening situation, an alarm can be sent to an expert.
According to typical embodiments, at least two adjacent to at proximal and distal points of a stent are provided, which are configured to monitor the relative pressures difference between the two sensors. Multiple chips can also be designed within a stent another or support structure and therefore spatially relative pressures will be measured and recorded for any abnormality identification.
According to some embodiments, which can be combined with other embodiments described herein, the devices and systems employ multiple sensors and measure the spatially relative pressure differences. Accordingly, variations in blood pressure due to stress or other abnormal health conditions can be compensated as the pressure difference at two predetermined positions, e.g. a proximal and distal end of a stent or a graft, is measured. Hence, embodiments facilitate detection of any abnormality within the stent in a simpler and more reliable manner compared to measurements with one sensor. Furthermore, in case one of the sensing devices would be malfunctioning due to a failure or due to extensive plaque covers on one of the sensing devices (chips), the other(s) sensing devices can continue providing information.
According to some embodiments, which can be combined with other embodiments described herein, the devices and systems employ multiple sensors and/or chips and measure the spatially relative pressure differences. Accordingly, the first measurements right after implantation can be deploy for data calibration. The data calibration includes measured relative pressure differences, which are served to assess disease severity under different psychological and physical conditions (e.g. rest, exercise, stress, etc.). For example, saturation of sensors can be an indicative for abrupt or gradual changes in disease severity.
According to typical embodiments, which can be combined with other embodiments described herein, the sensors 110 can be radio-frequency chips or integrated with radio-frequency chips, similar to RFID chips. Thereby, the sensors are powered by an external RF source, e.g. in the GHz range, such as 2 GHz to 100 GHz. On receiving energy by the external source, the sensors 110 provide pressure values of the actual pressure at the sensor. The pressure values are transmitted with a wireless connection to an external reading device. According to a typical example, the external RF source and the reading device can be integrated in one remote device for powering and reading the sensors.
During operation such a remote device or the respective RF source and the reading device can be held next the patient's body part, in which the stent 20 with the sensor 110 is implanted for a predetermined period of time. The pressure values can e.g. be read during a time period ranging from 5 seconds to 5 minutes, e.g. 2 min. A few heart cycles can be measured in that time period. Thereby, statistically improved pressure values, e.g. average values or values optimized by other statistic models (e.g. variance correlation) and signal processing technique (e.g. spectral analysis) can be obtained. The limitation to a predetermined time period further has the benefit that possible heat generation due to energy consumption of the chip can be limited to a time span, which is harmless to the tissue of the blood vessel in which the stent is implanted.
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As described above, the support structure, which is configured to be implanted in a human or animal body together with the sensors 110, can be provided by a stent or a graft. However, according to yet further embodiments, which can be combined with other embodiments described herein, the support structure can also be provided by a stent arrangement comprising two or more stents.
According to typical embodiments described herein, the sensor can be provided by a MEMS (micro-electro-mechanical system). Thereby, a chip can be provided with a pressure sensor, a wireless power supply (see, e.g. RFID), a microelectronics and an antenna for transmitting the pressure values and/or further parameter values, or even a sensor ID to an external receiver or reading device. Accordingly, the sensor can include an HF frontend module for transmitting the sensed values as a function of time. The entire electronic can be provided on the chip. The sensor or chip further includes the measurement device or mechanical device, e.g. the pressure gauge, a wireless power supply, wherein the energy is transmitted by RF radiation, e.g. in the GHz range to the sensor, and optionally also a control unit and/or evaluation unit. According to alternatives a control unit and/or evaluation unit can also be provided in a remote reading device receiving the data.
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As described above, a support structure, which is configured to be implanted in a human or animal body together with the sensors 110, is provided. Thereby, as already shown in
According to some embodiments, which can be combined with other embodiments described herein, the support structure can include: a stent, a stent arrangement, a graft, a graft arrangement, two or more rings, or two or more plates, e.g. plate patches, or other elements or medical devices that can be inserted in a vessel. Thereby, according to some additional or alternative implementations, a ring can be provided as a short stent, i.e. a stent with a length in axial direction of 5 mm or below. Unlike stents, the rings are not employed or configured to push away plaques toward arterial walls and open up the site of occlusion but employed through balloon angioplasty by placing them at distal or proximal ends of an inflating balloon. The primary role of the rings is to facilitate online monitoring of disease progression through presented embodiments. The rings and support structures can according to some embodiments, which can be combined with other embodiments described herein, be self-expandable. According to typical embodiments, which can be combined with other embodiments described herein, the ring can be round, oval or any other shape configured to be arranged in a vessel of an animal or human.
According to yet further embodiments, the sensors can have any predetermined longitudinal position along the support structure, e.g. the stent arrangement or ring arrangement, which provides a sufficient distance between a first sensor and a second sensor to sense a pressure difference indicative of the health condition to be monitored. Thereby, according to typical embodiments described herein, which can be combined with other embodiments described herein, the predetermined position is defined merely by a longitudinal position, i.e. a rotation along the longitudinal axis is not considered and measurement results are irrespective thereof. This can, for example, be provided by the fact that pressure differences are considered.
According to yet further embodiments, as illustrated in
Further, according to yet further embodiments, also 3, 4 or 5 sensors can be provided at one ring. Providing two or more sensors at the ring can increase the measurement accuracy because more than one signal can be obtained at one axial position, i.e. the axial position of the ring having the two or more sensors. Further, redundancy is provided in the event one of the two or more sensors fails to provide reliable signals, e.g. because of a failure or by coverage of plaque. In case one of the sensing devices would be malfunctioning due to a failure or due to extensive plaque covers on one of the sensing devices (chips), the other(s) sensing devices can continue providing information.
According to some embodiments, which can be combined with other embodiments described herein, two rings 820, each with at least one sensor 110, forms a medical device 1200, as e.g. shown in
Particularly for embodiment, wherein two or more rings are used as a support structure for the sensors and thereby forming a medical device, additional benefits can be obtained. In a first treatment a balloon angioplasty (see box 114) can be provided. A balloon pushes away the plaque in a vessel. During balloon angioplasty to rings, each with at least one pressure sensor can be implanted. Thereby, atherosclerosis or other stenotic or vascular disease can be treated and at the same time a valuable monitor ability can be provided. Accordingly, a stent implantation can be postponed, whereby the risk during postponing the stent implantation can be determined by the monitoring capability of the medical devices according to some embodiments described herein. Such a surgery could be repeated, e.g. after one or two years as indicated by arrow 115.
In the event atherosclerosis or other stenotic or vascular disease could not be stopped, a stent implantation (box 116) could be postponed with a good risk management. Thereby, several years (e.g. 1 to 3) can be gained before a stent implantation and consequently also before bypass surgery (see box 118) as a further step after stent implantation. In addition for stent implantation and/or for bypass surgery, a monitoring capability can be provided by embodiments described herein. This is indicated by arrows 117 and 119. It is to be understood that the monitoring can be added in the same surgery as the stent implantation or the bypass surgery even though arrows 117 and 119 point back to the balloon angioplasty.
According to typical embodiments described herein, the sensors can be provided by a MEMS (micro-electro-mechanical system). Thereby, a chip can be provided with a pressure sensor, a wireless power supply (see, e.g. RFID), a microelectronics and an antenna for transmitting the pressure values and/or further parameter values, or even a sensor ID to an external receiver or reading device. Accordingly, the sensor can include an HF frontend module for transmitting the sensed values as a function of time. The entire electronic can be provided on the chip. The sensor or chip further includes the measurement device or mechanical device, e.g. the pressure gauge, a wireless power supply, wherein the energy is transmitted by RF radiation, e.g. in the GHz range to the sensor, and optionally also a control unit and/or evaluation unit. According to alternatives a control unit and/or evaluation unit can also be provided in a remote reading device receiving the data.
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Accordingly, embodiments described herein serve for health monitoring of atherosclerotic disease, stenotic disease, other vascular disease, e.g. stenosis or restenosis after stent implantation, stent breakage, or the like. Embodiments described herein, can yield yet further embodiments, when utilized as methods where a continuous monitoring is provided. E.g. remote device can be placed external to a human or animal body in the vicinity of or directed towards the implanted sensor(s) on a regular basis, e.g. daily or weekly or the like and the data can be transferred and evaluated accordingly. Thereby, growing restenosis can be sensed at an early stage.
The sensor or sensors provided use RF energizing techniques such as or similar to RFID chips. Thereby, the implanted sensor or sensors can be miniaturized sufficiently to also be provided in cardiovascular vessels, where stent length of 1.0 mm to 20 mm or other places at the human or animal body where stent length of 2 cm to 20 cm are utilized. According to yet further additional or alternative modifications, the implanted sensor or sensors can be miniaturized sufficiently to also be provided in vessels, where stent diameters are from 0.5 mm to 20 mm, e.g. from 1 mm to 15 mm, such as from 1 mm to 10 mm. Accordingly, the sensor can be miniaturized to a degree beyond previously known sensor for implantation. According to yet further embodiments, which can be combined with other embodiments described herein, two or more sensors are provided, wherein a pressure difference of at least two sensors is sensed. This simplifies and improves sensing of the health condition. Further, rotational positioning can be disregarded. According to yet further embodiments, which can be combined with other embodiments described herein, the support structure can be the stent or two or more stents, which are implanted for curing the vascular or cardiovascular disease. Accordingly, the health monitoring device is in place at least after the surgery for treating the original disease. Thereby, according to optional modifications, a calibration of the freshly implanted stent, e.g. an initial pressure difference can be provided.
According to yet further embodiments, which can be combined with other embodiments described herein, the sensor can be provided in a chip, e.g. as MEMS and/or as silicon based integrated HF circuits and particularly, with wireless broadband communication. Typically, the sensor can be a SoC (System on Chip), wherein sterile packaging can be provided as known in the art.
Data transmission from the sensor occurs initially to a remote device, e.g. a smart phone or another device, and is typically provided to a backend server portal, e.g. in the form of a server cloud solution. The server solution can allow, e.g. with encrypted communication such as AES, reference to a plurality of sensor information, historical data, medication information, expert information from a doctor and other information of interest for a user. The information can be graphically shown to the user for ease of understanding. Further, a cloud solution allows access from different location and also access of different persons, e.g. doctors or emergency physicians.
According to yet further embodiments, which can be combined with other embodiments described herein, a sensing system for quasi-continuous sensing as described herein and methods of monitoring, can further include a test phase with a medication model A, where a plurality of measurement cycles are conducted for a time period of days or weeks and a test phase with a medication model B, where another plurality of measurement cycles are conducted for a period of days or weeks, such that an individual medication for each patient can be developed efficiently.
While the foregoing is directed to embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.
Number | Date | Country | Kind |
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12177301.4 | Jul 2012 | EP | regional |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2013/065322 | 7/19/2013 | WO | 00 |