187 results about "Myocardial Fractional Flow Reserve" patented technology

A method and system for determining fractional flow reserve (FFR) for a coronary artery stenosis of a patient is disclosed. In one embodiment, medical image data of the patient including the stenosis is received, a set of features for the stenosis is extracted from the medical image data of the patient, and an FFR value for the stenosis is determined based on the extracted set of features using a trained machine-learning based mapping. In another embodiment, a medical image of the patient including the stenosis of interest is received, image patches corresponding to the stenosis of interest and a coronary tree of the patient are detected, an FFR value for the stenosis of interest is determined using a trained deep neural network regressor applied directly to the detected image patches.

A method and system for multi-scale anatomical and functional modeling of coronary circulation is disclosed. A patient-specific anatomical model of coronary arteries and the heart is generated from medical image data of a patient. A multi-scale functional model of coronary circulation is generated based on the patient-specific anatomical model. Blood flow is simulated in at least one stenosis region of at least one coronary artery using the multi-scale function model of coronary circulation. Hemodynamic quantities, such as fractional flow reserve (FFR), are computed to determine a functional assessment of the stenosis, and virtual intervention simulations are performed using the multi-scale function model of coronary circulation for decision support and intervention planning.

Non-invasive systems and methods for determining fractional flow reserve. At least one method of determining fractional flow reserve within a luminal organ of the present disclosure comprising the steps of positioning a monitoring device external to a luminal organ and near a stenosis, the monitoring device capable of determining at least one characteristic of the stenosis, operating the monitoring device to determine the at least one characteristic of the stenosis, and determining fractional flow reserve at or near the stenosis based upon the at least one characteristic determined by the monitoring device.

Devices and systems for determining fractional flow reserve. In at least one embodiment of a device for determining fractional flow reserve of a fluid within a luminal organ, the device comprises an elongated body sized and shaped to fit within a luminal organ, and at least two sensors positioned along the elongated body a predetermined distance from one another, wherein the device is operable to detect a first fluid with a first parameter having a first value using at least one of the at least two sensors when the device is positioned within the luminal organ, and wherein the device is further operable to detect a second fluid having a second parameter, wherein the second parameter of the second fluid has a second value different from the first value, upon introduction of the second fluid within the luminal organ at or near the at least two sensors, and wherein the device is further operable to determine fractional flow reserve when the device is positioned within the luminal organ at or near a stenosis, wherein the fractional flow reserve is based upon a flow velocity obtained by the device, a mean aortic pressure within the luminal organ, and at least one cross-sectional area at or near the stenosis.

In part, the invention relates to methods, apparatus, and systems suitable for determining a fractional flow reserve (FFR) and variations of modifications thereof One embodiment relates to a method and apparatus for obtaining a corrected FFR in a vessel having a stenosis. In one aspect, the invention relates to an apparatus for measuring corrected FFR of a vessel having a stenosis. In one embodiment, the apparatus includes a probe comprising an optical coherence tomography assembly and a pressure assembly; and a processor in communication with the optical coherence tomography assembly and the pressure assembly. In one embodiment, the pressure assembly measures values of pressure in predetermined locations the vessel and communicates them to the processor. In one embodiment, a dual guidewire is used to reduce the interference in the pressure measurement.

In one aspect, the invention relates to system comprising: a processor configured to receive a first optical coherence tomography (OCT) data set obtained during a pullback of a data collection probe along a first length of a first blood vessel; determine a minimum lumen area disposed along the first length using the first OCT data set; and determine a first FFR value along the first length based on the minimum lumen area. In one embodiment, the first FFR value is an estimated FFR. In another aspect, the invention relates to a method that includes measuring, using OCT, the area of a lumen of a vessel for which the vessel's FFR is to be determined; and calculating, using a computer, A²m/(A²m+k) or Y^A2min/(Y^A2min+k) as a FFR value. In one embodiment, k is about 0.7 mm2 and γ is patient-specific variable that depends on the coronary branch in which the images were obtained.

A medical system includes a medical instrument (102) configured for interventional deployment and a shape sensing system (104) mounted on or in the medical instrument and configured to measure a shape of the medical instrument during the interventional deployment. An imaging device (106) is mounted on or in the medical instrument and configured to image a lumen in which the imaging device is deployed. A registration module (140) is configured to register the shape of the medical instrument to an image of the lumen at a particular time to reconstruct a three-dimensional geometry of the lumen, accounting for motion.

A method and system for prediction of post-stenting hemodynamic metrics for treatment planning of arterial stenosis is disclosed. A pre-stenting patient-specific anatomical model of the coronary arteries is extracted from medical image data of a patient Blood flow is simulated in the pre-stenting patient-specific anatomical model of the coronary arteries with a modified pressure-drop model that simulates an effect of stenting on a target stenosis region used to compute a pressure drop over the target stenosis region. Parameter values for the modified pressure-drop model are set without modifying the pre-stenting patient-specific anatomical model of the coronary arteries. A predicted post-stenting hemodynamic metric for the target stenosis region, such as fractional flow reserve (FFR), is calculated based on the pressure-drop over the target stenosis region computed using the modified pressure-drop model.

A method of determining fractional flow reserve (FFR) in a blood vessel having stenosis includes injecting fluid into the blood vessel upstream of the stenosis using a power fluid injector, measuring pressure drop across the stenosis, and calculating FFR from measured pressure drop. The injected fluid may comprise a contrast medium. Further actions may include placing a pressure sensor proximal of the stenosis, injecting fluid into the blood vessel upstream of the stenosis using the power fluid injector, and measuring pressure in the blood vessel proximal of the stenosis. The pressure sensor may then be repositioned to a position distal of the stenosis, fluid may be reinjected into the blood vessel upstream of the stenosis using the power fluid injector, and pressure may be measured in the blood vessel distal of the stenosis.

A predetermined time-based index ratio such as time-based fractional flow reserve (FFR) is determined for evaluating a level of blood circulation between at least two locations such as a proximal location and a distal location in a selected blood vessel in the region of interest. One time-based FFR is obtained by normalizing a risk artery ratio by a reference artery ratio.

The invention relates to a hemodynamic fast planning method for personalized coronary artery bypass graft surgery. According to the method, a personalized coronary artery lumped parameter model is built according to information of a patient, the coronary artery fractional flow reserve for reflecting coronary artery functional diseases is calculated, the surgery indication is evaluated, and in combination with SYNTAX grading of anatomic disease extension, the evaluation is used as the comprehensive evaluation basis for selecting a coronary artery bypass graft surgery strategy. A bypass graft scheme is selected on the premise of adaptation and involves the bypass graft blood vessel number, the bypass graft position, the transfer catheter type and the like. The personalized lumped parameter model is calculated, and postoperative coronary artery flow and pressure changes and postoperative bypass graft blood vessel parameters are obtained. According to the average wall shear stress, the wall shear stress oscillation index and the competitive flow degree, the long-term permeability of the transfer catheter of the scheme is analyzed. The long-term permeability of transfer catheters in different bypass graft schemes is compared, and the best bypass graft scheme is obtained. The hemodynamic fast planning method solves the problems that an existing method is invasive, indirect, long in consumed time and the like.

An intravascular sensor delivery device for measuring a physiological parameter of a patient, such as blood pressure, within a vascular structure or passage. In some embodiments, the device can be used to measure the pressure gradient across a stenotic lesion or heart valve, such as a fractional flow reserve (FFR) across a stenotic lesion. The sensor delivery device has a distal sleeve configured to pass or slide over a standard medical guidewire. The sensor delivery device can be sized to pass over different sizes of guidewires to enable usage in coronary and peripheral arteries, for example. The sensing mechanism (sensor) can be a fiber optic pressure sensor, such as a MEMS-based FabryPerot fiber optic pressure sensor, for example, or could employ some other technology, e.g., MEMS capacitive or piezoresistive sensor.

This invention describes methods to compute coronary physiology indexes using a high precision registration model, which consists of acquiring coronary angiography images of coronary vessels, performing intravascular imaging, and registering the coronary angiography images with intravascular images to create a high precision registration model, based upon which the coronary flow, fractional flow reserve (FFR) and index of microcirculation resistance (IMR) can be computed. The methods described in this invention to compute coronary flow, FFR, IMR are based on both coronary angiography and intravascular images, and the accuracy is better than those derived from coronary angiography alone or intravascular imaging alone, and have high practical values.

An embodiment in accordance with the present invention provides a method for non-invasively determining the functional severity of coronary artery stenosis. The method includes gathering patient-specific data related to concentration of a contrast agent within a coronary artery of a patient using a coronary computed tomography angiography scan (CCTA). The patient-specific data is used to calculate a patient-specific transluminal attenuation gradient for the coronary artery of the patient. The patient specific transluminal attenuation gradient is used to determine an estimate of a coronary flow velocity, pressure gradient, loss coefficient, coronary flow reserve, and/or fractional flow reserve for the patient. Coronary flow velocity, pressure gradient, loss coefficient, coronary flow reserve, and fractional flow reserve can then be used to estimate the functional severity of coronary artery stenosis.

Embodiments hereof relate to methods and systems for determining a pressure gradient across a lesion of a vessel without requiring the use of a pharmacological hyperemic agent. A measurement system includes at least an injection catheter and a pressure-sensing instrument or guidewire slidingly disposed through the catheter, the pressure-sensing guidewire including at least one pressure sensor configured to obtain a pressure measurement for use in determining the pressure gradient across the lesion. The catheter is configured to deliver or inject a non-pharmacological fluid, such as saline or blood, across the lesion in order to increase a flow rate there-through, thereby simulating hyperemia without the use of a pharmacological hyperemic agent. Once an increased flow rate that simulates hyperemia is achieved, the pressure sensor of the pressure-sensing guidewire may be utilized to measure the pressure gradient across the lesion in order to assess the severity of the lesion.

A method and system for anatomical object detection using marginal space deep neural networks is disclosed. The pose parameter space for an anatomical object is divided into a series of marginal search spaces with increasing dimensionality. A respective deep neural network is trained for each of the marginal search spaces, resulting in a series of trained deep neural networks. Each of the trained deep neural networks can evaluate hypotheses in a current parameter space using discriminative classification or a regression function. An anatomical object is detected in a medical image by sequentially applying the series of trained deep neural networks to the medical image.

A catheter includes an elongate shaft including a proximal portion and a distal portion extending from the proximal portion to a distal opening at a distal end of the shaft. The proximal portion defines a proximal guidewire lumen and has a first outer diameter. The distal portion defines a distal guidewire lumen in communication with the proximal guidewire lumen and has a second outer diameter smaller than the first outer diameter. A pressure sensor is coupled to the proximal portion such that the pressure sensor faces the proximal guidewire lumen. When the catheter is tracked to a treatment site within the vasculature, the pressure sensor is disposed proximal the treatment site, the distal opening is disposed distal to the treatment site, and the distal guidewire lumen fills with blood such that the pressure sensor senses a pressure of the blood at the distal end of the shaft.

A medical system for determining the individual Fractional Flow Reserve (FFR) value for one or many lesions of interest of a blood vessel, the system comprising an intravascular pressure measurement device for acquiring pressure measurements in the blood vessel during continuous blood flow there through. The pressure measurement device comprises a pressure sensor at its distal portion. The system further comprises an FFR processor adapted to determine the FFR value related to said lesion solely/only based upon the pressure measurements performed by said pressure sensor.

The invention discloses a method, device and system for acquiring the fractional flow reserve, and a computer storage medium. The method for acquiring the fractional flow reserve comprises: a step S1,acquiring image data and physiological parameters related to a coronary artery and a heart, and constructing a corresponding three-dimensional model by processing the image data; a step S2, solving ahemodynamic control equation according to the three-dimensional model to obtain a hemodynamic parameter distribution of the coronary artery in a region expressed by the three-dimensional model, wherein the hemodynamic parameter of a boundary portion of the three-dimensional model is obtained by using a lumped model and a genetic algorithm; a step S3, calculating the fractional flow reserve of theangiostenosis site according to the relevant parameter obtained in step S2; and step S4, generating a corresponding fractional flow reserve report on the basis of the result of step S3. The method can accurately calculate and acquire of the fractional flow reserve FFR of the coronary artery of a patient.