46 results about "Afterload" patented technology

An extracardiac pumping for supplementing the circulation of blood, including the cardiac output, in a patient without any component thereof being connected to the patient's heart, and methods of using same. One embodiment of the intravascular extracardiac system comprises a pump with inflow and outflow conduits that are sized and configured to be implantable intravascularly through a non-primary vessel, whereby it may positioned where desired within the patient's vasculature. The system comprises a subcardiac pump that may be driven directly or electromagnetically from within or without the patient. The pump is configured to be operated continuously or in a pulsatile fashion, synchronous with the patient's heart, thereby potentially reducing the afterload of the heart. In another embodiment, the system is positioned extracorporeally, with the inflow conduit and outflow conduit applied percutaneously to a non-primary vessel for circulating blood to and from the non-primary vessel or between the non-primary vessel and another blood vessel within the patient's vasculature.

A method of and a device for non-invasively measuring the neurological depressed state and the hemodynamic state of a human patient and involving steps and units of non-invasively measuring EEG, cardiac cycle period, electrical-mechanical interval, mean arterial pressure, and ejection interval and converting the EEG into a neurological index as well as converting the measured electrical-mechanical interval, mean arterial pressure and ejection interval into the cardiac parameters such as Preload, Afterload and Contractility, which are the common cardiac parameters used by an anesthesiologist. A general anesthetic is administered based upon the converted neurological index. A vasoactive agent is independently administered based upon the converted cardiac parameters as necessary in order to restore cardiovascular homeostasis in the patient. The converted neurological and hemodynamic state of a patient are displayed on a screen as an index value and a three-dimensional vector with each of its three coordinates respectively representing Preload, Afterload and Contractility. Therefore, a medical practitioner looks at the screen and quickly obtains the important and necessary information.

An apparatus and method for assessing myocardial wall stress is disclosed. The method may be used in conjunction with electro-stimulatory therapy for preventing or reversing ventricular remodeling. In such therapy, one or more stimulatory pulses are delivered to the heart such that a stressed region of the myocardium is pre-excited relative to other regions, thereby subjecting the stressed region to a lessened preload and afterload during systole. The unloading of the stressed myocardium over time effects reversal of undesirable ventricular remodeling.

An apparatus and method for reversing ventricular remodeling with electro-stimulatory therapy. A ventricle is paced by delivering one or more stimulatory pulses in a manner such that a stressed region of the myocardium is pre-excited relative to other regions in order to subject the stressed region to a lessened preload and afterload during systole. The unloading of the stressed myocardium over time effects reversal of undesirable ventricular remodeling.

Provided herein are implantable systems that include an implantable photoplethysmography (PPG) sensor, which can be used to obtain an arterial PPG waveform. In an embodiment, a metric of a terminal portion of an arterial PPG waveform is determined, and a metric of an initial portion of the arterial PPG waveform is determined, and a surrogate of mean arterial pressure is determined based on the metric of the terminal portion and the metric of the initial portion. In another embodiment, a surrogate of diastolic pressure is determined based on a metric of a terminal portion of an arterial PPG waveform. In a further embodiment, a surrogate of cardiac afterload is determined based on a metric of a terminal portion of an arterial PPG waveform.

Methods and associated algorithms for determining cardiac and/or cardiovascular performance that are based on at least one cardiac function determinant associated with or at least in part, reflective of preload, contractility and afterload.

The invention provides a treatment for congestive heart failure (CHF) in a patient. At least one pressure applicator is arranged externally around a body segment of the patient. Negative pressure, relative to atmospheric pressure, is applied to the body segment of the patient during cardiac systole using the pressure applicator, thereby reducing ventricular afterload in the patient. The negative pressure to the body segment of the patient is removed during cardiac diastole.

A method and system is provided for determining the cardiac contractility of a cardiovascular system. The method includes utilizing values representing stroke volume, preload, and afterload to calculate the cardiac contractility. The calculation may include a mathematical relationship in which the cardiac contractility is represented by a first edge of a tetrahedron, the preload is represented by a second edge of the tetrahedron, the afterload is represented by a third edge of the tetrahedron, and the stroke volume is represented by the volume of the tetrahedron. A display apparatus is also provided. The display apparatus includes a schematic representation of a tetrahedron and indicia indicating that the cardiac contractility, the preload, the afterload, and the stroke volume are represented by mutually distinct parameters of the tetrahedron.

The invention discloses a novel closestool. A seat ring of the closestool is in a saddle type; the height difference between the lowest points of the upper end surface and the lower end surface of the seat ring is 55 to 60mm; the length of the seat ring is 280 to 290mm; the width of the seat ring is 350 to 360mm; the length of a seat ring hole formed in the seat ring is 230 to 250mm; the width of the seat ring hole is 170 to 190mm; an included angle between a connecting line between the lowest point of the lower end surface and the highest point of the front end of the upper end surface of the seat ring, and the horizontal tangent line of the lowest point of the lower end surface is 15 to 20 degrees; an included angle between the connecting line between the lowest point of the lower end surface and the highest point of the rear end of the upper end surface of the seat ring, and the horizontal tangent line of the lowest point of the lower end surface is 30 to 45 degrees. The novel closestool has the advantages that in the use process, the lower limbs naturally droop; the skeletal muscle is relaxant; the returned blood volume is reduced; the afterload of the heart is reduced; the elevation-angle-increase sitting posture defecation is realized, so that the defecation body position is comfortable and smooth; the novel closestool conforms to the defecation habit; the defecation time is shortened, so that the constipation occurrence rate is reduced.

A device and method for analyzing of a disturbed pattern of pulse wave front results in a non-invasive, real-time diagnostic tool of arterial vascular performance on both a global and regional scale. The device provides a single number quantifying how well the arterial tree as a whole is coupled to receive and distribute a stroke volume of a single heartbeat. Changing heart rate, contractility, volume status, and afterload will change stroke volume and ejection time. Different vasculatures with different properties (e.g., size and intrinsic stiffness) will be best matched for different stroke volumes and ejection times to provide optimal coupling. The device will allow finding the optimal set of parameters for individual patient.

The invention discloses an FFR rapid calculation system model based on a zero-dimensional hemodynamic model, which belongs to the field of hemodynamic numerical simulation. The system comprises a personalized zero-dimensional hemodynamic construction model, a stenosis resistance theoretical calculation model, a stenosis resistance determination model and an FFR model. In a resting state, the zero-dimensional model is personalized through coronary artery post-load and other model parameters including the heart. In a hyperemia state, the stenosis resistance output by the resistance model is taken as the input of the zero-dimensional model to influence the flow distribution of each branch of the coronary artery of the zero-dimensional model, and the stenosis branch flow output by the zero-dimensional model is taken as the input of the resistance model to recalculate the stenosis resistance. The two models are repeatedly iterated until the flow is matched with the resistance, the stenosisresistance is finally determined, the pressure of each branch of the coronary artery is obtained, and the FFR is calculated according to the ratio of the average pressure of the distal stenosis end tothe average pressure of the root of the aorta in the hyperemia state. The system can quickly and accurately calculate the FFR. The system is rapid and accurate.

The invention belongs to the traditional Chinese medicine field, and relates to corynoxeine and an application of an isomer of the corynoxeine in preparing medicines. In the invention, the results of animal experiments prove that the corynoxeine and the isomer thereof have the effects of expanding vessels and lowering blood pressure, and can be used for preparing the medicines for expanding the vessels and lowering the blood pressure; the corynoxeine and isocorynoxeine have the effects of expanding the vessels, lowering heart afterload, lightening heart burden and decreasing myocardial oxygen consumption, and can be used for preparing anti-angina pectoris medicines; the corynoxeine has the effects of negative myodynamia, directly decreasing the myocardial oxygen consumption, and doubly lowering the myocardial oxygen consumption; the corynoxeine and the isocorynoxeine have the effects of improving the ventricular muscle excited threshold and lowering the ventricular muscle contraction frequency, can be used for treating ventricular tachycardia, and can be used as a quality identification uncaria and tagged molecules of the ffective parts of the corynoxeine and the isocorynoxeine.

The invention discloses a high-flow pulsating electromagnetic blood pump, which comprises a mounting bracket. At least two magnetic pushing devices mounted on the support surface, the magnetic pushingdevices comprising a drive coil, a permanent magnet piston, a two-way joint, an inner bag and a magnetic shielding cylinder; At least one set of linkage assemblies for linkage of permanent magnet pistons in two of the magnetic propulsion devices of the same set reciprocating alternately; A processor for controlling a control circuit of the driving coil by a set rhythm or according to an electrocardiogram signal of a human body surface; And an electrocardiogram electrode for detecting and transmitting a body surface electrocardiogram signal of the human body to the processor. The invention integrates a plurality of magnetic pushing devices and is linked by the linkage components in two groups, thereby effectively reducing heat generation, increasing the power of the whole machine in multiple, simultaneously increasing the flow rate, and effectively improving the working condition. It can also be controlled according to extracorporeal electrocardiogram signals, which can avoid increasing the afterload of myocardium in systolic phase.

An examination device for a heart. An afterload device connected to the aorta provides a counterpressure by an annular space delimited between a rigid cylinder and an elastic tube inserted in the rigid cylinder. The annular space comprises a compressible medium, such as air, nitrogen gas or carbon dioxide and is connected to a reservoir providing a predetermined pressure corresponding to a diastolic pressure. The reservoir is connected to the annular space via a restriction and a back-flow valve. During diastole, the annular space is inflated by the reservoir and provides a diastolic counter pressure for providing coronary flow. During systole, the ejected fluid from the heart ventricle displaces the medium inside the annular space through the restriction to the reservoir, thereby removing energy from the fluid. The compressible medium forms a compliance. In addition, there is a preload device comprising a vertical collapsible tube forming a fluid column for preload of the atrium with a desired preload pressure without introducing air into the fluid. A pump delivers fluid to the preload device and removes fluid from the afterload device.