Disclosure of Invention
Accordingly, the present invention is directed to a method, an apparatus and a storage medium for calculating the left outflow tract cross-sectional area, which solve the problems in the prior art that the degree of the obstruction of the heart outflow tract of the user is judged by the pressure difference, the pressure difference is affected by the cardiac output, and when the degree of the obstruction of the heart outflow tract of the user is unchanged, that is, the morphology of the blood flow cavity at the outflow tract is unchanged, the pressure difference is reduced due to the reduction of the cardiac output, so that the severity of the obstruction of the patient is underestimated.
According to a first aspect of an embodiment of the present invention, there is provided a left-hand chamber outflow channel cross-sectional area calculating method, including:
obtaining the relation between the pressure difference from the left chamber cavity to the outflow tract section, the systolic flow and the cross-sectional area of the outflow tract according to the relation between the blood flow velocity of the outflow tract of the left chamber and the systolic flow and the cross-sectional area of the outflow tract;
according to the relation between the systolic flow and the cardiac output, respectively obtaining the relation between the cardiac output and the cross-sectional area of the outflow tract and the pressure difference from the left chamber cavity to the outflow tract section, and the relation between the cardiac output and the cross-sectional area of the outflow tract and the blood flow velocity of the outflow tract of the left chamber;
acquiring cardiac output of a user, blood flow velocity of an outflow tract of a left chamber and pressure difference between a cavity of the left chamber and an outflow tract section;
calculating the cross-sectional area of the outflow tract according to the relation between the cardiac output and the cross-sectional area of the outflow tract and the pressure difference between the left chamber and the outflow tract, or calculating the cross-sectional area of the outflow tract according to the relation between the cardiac output and the cross-sectional area of the outflow tract and the blood flow velocity of the outflow tract of the left chamber;
the obstruction degree of the left outflow tract of the user is judged through the cross-sectional area of the outflow tract.
Preferably, the method further comprises:
acquiring the aortic blood flow velocity of a user, measuring the cardiac output of the user, and calculating the cross-sectional area of the aortic valve according to the cardiac output and the relation between the cross-sectional area of the aortic valve and the aortic blood flow velocity;
the aortic valve stenosis of the user is judged by the cross-sectional area at the aortic valve.
Preferably, the method comprises the steps of,
the formula for obtaining the relation between the pressure difference from the left chamber cavity to the outflow tract section, the systolic flow and the cross-sectional area of the outflow tract according to the relation between the blood flow velocity of the outflow tract of the left chamber and the systolic flow and the cross-sectional area of the outflow tract is as follows:
in the method, in the process of the invention,indicating systolic flow, +.>Indicating the cross-sectional area at the outflow tract.
Preferably, the method comprises the steps of,
the formula of the relationship between systolic flow and cardiac output is as follows:
in the method, in the process of the invention,representing cardiac output;
the process of respectively obtaining the relation between the cardiac output and the cross-sectional area of the outflow tract and the pressure difference from the left chamber to the outflow tract according to the relation between the systolic flow and the cardiac output, and the relation between the cross-sectional area of the outflow tract and the blood flow velocity of the outflow tract of the left chamber is as follows:
；
the conversion of this formula yields respectively:
。
preferably, the method comprises the steps of,
the formula for calculating the cross-sectional area at the aortic valve according to the relation between the cardiac output and the aortic blood flow velocity is as follows:
；
in the method, in the process of the invention,represents the cross-sectional area at the aortic valve->Representing the blood flow velocity at the aortic valve.
According to a second aspect of an embodiment of the present invention, there is provided a left-hand chamber outflow tract cross-sectional area calculating device, the device including:
the first cross-sectional area relation acquisition module: the method is used for obtaining the relation between the pressure difference from the left chamber cavity to the outflow tract section, the systolic flow and the cross-sectional area of the outflow tract according to the relation between the blood flow velocity of the outflow tract of the left chamber and the systolic flow and the cross-sectional area of the outflow tract;
a second cross-sectional area relation acquisition module: the method is used for respectively obtaining the relation between the cardiac output and the left chamber cavity to outflow tract section pressure difference and the relation between the cardiac output and the outflow tract cross-sectional area and the left chamber outflow tract blood flow velocity according to the relation between the systolic flow and the cardiac output;
and a data acquisition module: the method comprises the steps of acquiring cardiac output of a user, blood flow velocity of an outflow tract of a left chamber and pressure difference from a cavity of the left chamber to an outflow tract section;
the cross-sectional area calculation module: for calculating the outflow tract cross-sectional area based on the cardiac output and the relationship of the outflow tract cross-sectional area to the left chamber to outflow tract segment pressure differential, or calculating the outflow tract cross-sectional area based on the cardiac output and the relationship of the outflow tract cross-sectional area to the left chamber outflow tract blood flow velocity;
and a judging module: for determining the degree of left ventricular outflow tract obstruction of a user by the outflow tract cross-sectional area.
According to a third aspect of embodiments of the present invention, there is provided a storage medium storing a computer program which, when executed by a master, implements the steps of the above-described method.
The technical scheme provided by the embodiment of the invention can comprise the following beneficial effects:
according to the method, the cross-sectional area is introduced, the relation between the left-chamber outflow channel blood flow velocity and the systolic flow and the cross-sectional area at the outflow channel is obtained, the relation between the left-chamber-to-outflow channel section pressure difference and the systolic flow and the cross-sectional area at the outflow channel is obtained, the relation between the cardiac output and the outflow channel cross-sectional area and the left-chamber-to-outflow channel section pressure difference is obtained according to the relation between the left-chamber-to-outflow channel blood flow velocity and the systolic flow and the cross-sectional area at the outflow channel, and the relation between the cardiac output and the outflow channel cross-sectional area and the left-chamber-to-outflow channel blood flow velocity are obtained.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed.
Detailed Description
Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements, unless otherwise indicated. The implementations described in the following exemplary examples do not represent all implementations consistent with the invention. Rather, they are merely examples of apparatus and methods consistent with aspects of the invention as detailed in the accompanying claims.
Example 1
FIG. 1 is a flow diagram illustrating a method of calculating a left-hand outflow tract cross-sectional area, according to an exemplary embodiment, as shown in FIG. 1, the method comprising:
s1, obtaining the relation between the pressure difference from the left chamber cavity to the outflow tract section, the systolic flow and the cross-sectional area of the outflow tract according to the relation between the blood flow velocity of the outflow tract of the left chamber and the systolic flow and the cross-sectional area of the outflow tract;
s2, respectively obtaining the relation between the cardiac output and the cross-sectional area of the outflow tract and the pressure difference from the left chamber cavity to the outflow tract section and the relation between the cardiac output and the cross-sectional area of the outflow tract and the blood flow velocity of the outflow tract of the left chamber according to the relation between the systolic flow and the cardiac output;
s3, acquiring cardiac output of a user, blood flow velocity of an outflow tract of a left chamber and pressure difference from a cavity of the left chamber to a section of the outflow tract;
s4, calculating the cross-sectional area of the outflow tract according to the relation between the cardiac output and the cross-sectional area of the outflow tract and the pressure difference between the left chamber cavity and the outflow tract, or calculating the cross-sectional area of the outflow tract according to the relation between the cardiac output and the cross-sectional area of the outflow tract and the blood flow velocity of the left chamber outflow tract;
s5, judging the obstruction degree of the left outflow tract of the user through the cross section area of the outflow tract;
it will be appreciated that left ventricular outflow tract obstruction, as shown in fig. 2 or fig. 3, generally refers to a condition where the blood flow of a patient suffering from hypertrophic obstructive heart disease is blocked by the movement of the hypertrophic ventricular septum myocardium and the mitral valve SAM (systolic anterior motion) during systole and the heart cannot be effectively pumped, and the current clinical practice for quantitatively describing the cardiac outflow tract obstruction and aortic valve stenosis is mainly based on the differential pressure calculated based on the maximum flow rate of color doppler ultrasound measurement, in the figures,-systolic flow,/->-ascending aortic pressure (AA), +.>-outflow tract pressure, < >>-left chamber pressure,/->-ascending aortic blood flow velocity,/->-outflow tract blood flow velocity, < >>-left ventricular cavity blood flow velocity,/->Left chamber to outflow tract Duan Yacha, -a left chamber to outflow tract>-left ventricular chamber to aortic segment pressure drop, +.>-aortic valve->The mitral valve is present in the form of a mitral valve,based on the bernoulli equation used in color doppler ultrasound, one can get:
（1）
the formula applies when blood is considered to be an ideal fluid, without regard to energy loss due to obstruction of the blood flow lumen. In general, for patients with outflow obstruction and aortic stenosis, there is often an increase in blood flow velocity at the local stenosis, assuming thatAnd the above formula can be simplified to be without considering the influence of gravitational acceleration:
（2）
the formula 2 is a formula widely applied in color Doppler ultrasound for calculating pressure difference based on blood flow velocity, in this application, the above-mentioned obtaining of blood flow velocity of left ventricular outflow tract and pressure difference from left ventricular cavity to outflow tract actually obtains blood flow velocity of left ventricular outflow tract of user according to color Doppler ultrasound, then calculates from the above-mentioned formula 2 according to ideal Bernoulli equation to obtain left ventricular cavity to outflow tract Duan Yacha, according to the formula, the pressure difference measured by clinically used color Doppler ultrasound is completely determined by blood flow velocity at outflow tract and aortic valve, and is in quadratic relation with local blood flow velocity. According to clinical observation and related medical research, the local obstruction is greatly influenced by load conditions and myocardial contractility, and the characteristic of dynamic obstruction is presented, which is also a calculation formula for judging the obstruction degree of the outflow tract of the heart in the prior art, and the continuous deduction of the formula 2 can be obtained:
（3）
equation 3 demonstrates that the ultrasound differential pressure is primarily directly related to two physiological parameters of the patient, one being the outflow tract cross-sectional area and the otherIs cardiac output. The conclusion obtained by the formula is also more consistent with clinical observation and related medical research. When the form of the blood flow cavity at the outflow channel is unchangedAnd the pressure difference is kept unchanged), when the outflow obstruction is unchanged from the morphological point of view, the change of the cardiac output can directly influence the pressure difference measured by color Doppler ultrasound, and the pressure difference measured by the ultrasound is in a quadratic relation with the cardiac output of a patient. Clinically, patients with serious obstruction can observe that cardiac output is obviously reduced, and pressure difference measured by ultrasound is correspondingly smaller, so that the severity of the obstruction of the patients is underestimated. The difference in relevant evaluation is greater for patients with substantial regurgitation of the mitral valve during systole. Meanwhile, for patients with abnormal hypertrophic papillary muscles and obvious hypertrophy of the left ventricular wall, the reduction of cardiac output is also caused by the insufficient volume of the left ventricular cavity, and the pressure difference of the measured outflow tract is further smaller. There are also patients with left ventricular cavity middle obstruction, and the blood flow near the apex of the heart cannot be effectively pumped out of the heart in the systole, which also causes the reduction of cardiac output and the small pressure difference. The above-mentioned partial situation is serious, and judging the severity of the obstruction of the blood flow cavity and the aortic valve stenosis of the patient by singly measuring the pressure difference by color Doppler ultrasound may cause underestimation of the severity of the disease, and further cause the irrecoverable result, so the present application judges the obstruction degree of the outflow tract of the user by the cross-sectional area, and the cross-sectional area is determined by the morphology of the blood flow cavity at the obstruction position, and can be used for quantitatively describing the parameters of the obstruction condition at the heart, and can be directly calculated according to two common clinical parameters: ultrasonic measured outflow tract blood flow velocity, calculating pressure difference according to blood flow velocity, calculating cross-sectional area according to pressure difference and cardiac output, and similarly, we can calculate cross-sectional area according to outflow tract blood flow velocity and cardiac output, and obtaining cardiac output is a quite mature technology in the prior art, for example, patent publication No.: CN104739400B, patent name: the patent issued to the automatic cardiac output measurement system, in the solution of the present application, determines the severity of the obstruction of the user by the cross-sectional area of the outflow tract,compared with the problem that the judgment of the pressure difference can be influenced by the cardiac output in the prior art, the cross-sectional area is directly determined by the blood flow cavity morphology of the obstruction position and can be used for quantitatively describing parameters of the obstruction condition at the heart.
Preferably, the method further comprises:
acquiring the aortic blood flow velocity of a user through color Doppler ultrasound, measuring the cardiac output of the user, and calculating the cross-sectional area of the aortic valve according to the cardiac output and the relation between the cross-sectional area of the aortic valve and the aortic blood flow velocity;
judging the aortic valve stenosis degree of the user through the cross-sectional area of the aortic valve;
it will be appreciated that the above-described embodiment may be used to describe the stenosis of the aortic valve in addition to the degree of obstruction of the outflow tract, and the calculation principle is the same as that of the degree of obstruction of the outflow tract, except that the cross-sectional area of the aortic valve is calculated, and the calculation of the aortic blood flow velocity and the cardiac output is required when calculating the cross-sectional area of the aortic valve.
Based on Bernoulli equation, the formula for obtaining the pressure difference from the left chamber to the outflow tract section of the user through the blood flow velocity of the left chamber outflow tract is as follows:
（2）
in the method, in the process of the invention,representing the left chamber to outflow tract Duan Yacha, -a>Indicating left ventricular outflow tract blood flow velocity, < >>Represents blood density;
it will be appreciated that the left chamber to outflow tract pressure differential can be calculated from the acquired left chamber outflow tract blood flow velocity, which is a solution adopted in the prior art and is the basis for the subsequent calculation of the cross-sectional area in the present application.
Preferably, the method comprises the steps of,
the formula for obtaining the relation between the pressure difference from the left chamber cavity to the outflow tract section, the systolic flow and the cross-sectional area of the outflow tract according to the relation between the blood flow velocity of the outflow tract of the left chamber and the systolic flow and the cross-sectional area of the outflow tract is as follows:
in the method, in the process of the invention,indicating systolic flow, +.>Representing the cross-sectional area at the outflow tract;
it will be appreciated that by transforming equation 2 based on fig. 3, a relationship between left chamber to outflow tract differential systolic flow and outflow tract cross-sectional area can be obtained that shows how the outflow tract cross-sectional area can be calculated from cardiac output and differential pressure or left chamber outflow tract blood flow velocity.
Preferably, the method comprises the steps of,
the formula of the relationship between systolic flow and cardiac output is as follows:
in the method, in the process of the invention,representing cardiac output;
it will be appreciated that the systole normally occupies one third of the whole cardiac cycle, i.e. the systole requires pumping out the flow of the whole cardiac cycle in one third of the time, so
。
The process of respectively obtaining the relation between the cardiac output and the cross-sectional area of the outflow tract and the pressure difference from the left chamber to the outflow tract according to the relation between the systolic flow and the cardiac output, and the relation between the cross-sectional area of the outflow tract and the blood flow velocity of the outflow tract of the left chamber is as follows:
（3）
the conversion of this formula yields respectively:
（4）
；（5）
it will be appreciated that by transforming equation 3, two calculation equations for the outflow tract cross-sectional area, equation 4 and equation 5, can be obtained, and since cardiac output is available, left-ventricular outflow tract blood flow velocity is obtained by ultrasound, and left-ventricular outflow tract blood flow velocity can be calculated by the ideal bernoulli equation to obtain left-ventricular chamber to outflow tract segment differential pressure, either one of equations 4 and 5 can calculate outflow tract cross-sectional area.
Preferably, the method comprises the steps of,
the formula for calculating the cross-sectional area at the aortic valve according to the relation between the cardiac output and the aortic blood flow velocity is as follows:
；
in the method, in the process of the invention,represents the cross-sectional area at the aortic valve->Representing blood flow at aortic valveA degree;
it will be appreciated that when determining the stenosis of the aortic valve of the user, the cross-sectional area of the aortic valve is calculated on the same principle as the cross-sectional area of the outflow tract, and the cross-sectional area of the aortic valve is calculated by calculating the cardiac output and the aortic blood flow velocity, or by calculating the pressure drop from the left chamber to the aortic segment by the aortic blood flow velocity, and by calculating the pressure drop from the left chamber to the aortic segment and the cardiac output.
Example two
FIG. 4 is a system diagram illustrating a left chamber outflow tract cross-sectional area calculating device according to another exemplary embodiment, including:
first cross-sectional area relation acquisition module 1: the method is used for obtaining the relation between the pressure difference from the left chamber cavity to the outflow tract section, the systolic flow and the cross-sectional area of the outflow tract according to the relation between the blood flow velocity of the outflow tract of the left chamber and the systolic flow and the cross-sectional area of the outflow tract;
the second cross-sectional area relationship acquisition module 2: the method is used for respectively obtaining the relation between the cardiac output and the left chamber cavity to outflow tract section pressure difference and the relation between the cardiac output and the outflow tract cross-sectional area and the left chamber outflow tract blood flow velocity according to the relation between the systolic flow and the cardiac output;
data acquisition module 3: acquiring cardiac output of a user, blood flow velocity of an outflow tract of a left chamber and pressure difference between a cavity of the left chamber and an outflow tract section;
cross-sectional area calculation module 4: calculating the cross-sectional area of the outflow tract according to the relation between the cardiac output and the cross-sectional area of the outflow tract and the pressure difference between the left chamber and the outflow tract, or calculating the cross-sectional area of the outflow tract according to the relation between the cardiac output and the cross-sectional area of the outflow tract and the blood flow velocity of the outflow tract of the left chamber;
and a judging module 5: the method comprises the steps of judging the obstruction degree of a left outflow channel of a user through the cross-sectional area of the outflow channel;
it can be understood that the application also discloses a left-chamber outflow tract cross-sectional area calculating device, and the first cross-sectional area relation obtaining module 1 obtains the relation between the pressure difference from the left chamber cavity to the outflow tract section, the systolic flow and the cross-sectional area of the outflow tract according to the relation between the blood flow velocity of the left-chamber outflow tract, the systolic flow and the cross-sectional area of the outflow tract; the second cross-sectional area relation acquisition module 2 respectively acquires the relation between the cardiac output and the left chamber cavity to outflow tract section pressure difference and the relation between the cardiac output and the outflow tract cross-sectional area and the left chamber outflow tract blood flow velocity according to the relation between the systolic flow and the cardiac output; acquiring cardiac output of a user, blood flow velocity of an outflow tract of a left chamber and pressure difference from a cavity of the left chamber to an outflow tract section through a data acquisition module 3; the cross-sectional area calculating module 4 is used for calculating the cross-sectional area of the outflow tract according to the relation between the cardiac output and the cross-sectional area of the outflow tract and the pressure difference between the left chamber and the outflow tract, or calculating the cross-sectional area of the outflow tract according to the relation between the cardiac output and the cross-sectional area of the outflow tract and the blood flow velocity of the outflow tract of the left chamber; the judging module 5 judges the obstruction degree of the left outflow tract of the user through the cross section area of the outflow tract; the severity of the obstruction of the user is judged through the cross-sectional area of the outflow channel, compared with the problem that the influence of the cardiac output can be caused by the judgment of the pressure difference in the prior art, the cross-sectional area is directly determined by the blood flow cavity form of the obstruction position and can be used for quantitatively describing the parameters of the obstruction condition at the heart.
Embodiment III:
the present embodiment provides a storage medium storing a computer program which, when executed by a master controller, implements each step in the above method;
it is to be understood that the above-mentioned storage medium may be a read-only memory, a magnetic disk or an optical disk, etc.
It is to be understood that the same or similar parts in the above embodiments may be referred to each other, and that in some embodiments, the same or similar parts in other embodiments may be referred to.
It should be noted that in the description of the present invention, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Furthermore, in the description of the present invention, unless otherwise indicated, the meaning of "plurality" means at least two.
Any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps of the process, and further implementations are included within the scope of the preferred embodiment of the present invention in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the present invention.
It is to be understood that portions of the present invention may be implemented in hardware, software, firmware, or a combination thereof. In the above-described embodiments, the various steps or methods may be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, may be implemented using any one or combination of the following techniques, as is well known in the art: discrete logic circuits having logic gates for implementing logic functions on data signals, application specific integrated circuits having suitable combinational logic gates, programmable Gate Arrays (PGAs), field Programmable Gate Arrays (FPGAs), and the like.
Those of ordinary skill in the art will appreciate that all or a portion of the steps carried out in the method of the above-described embodiments may be implemented by a program to instruct related hardware, where the program may be stored in a computer readable storage medium, and where the program, when executed, includes one or a combination of the steps of the method embodiments.
In addition, each functional unit in the embodiments of the present invention may be integrated in one processing module, or each unit may exist alone physically, or two or more units may be integrated in one module. The integrated modules may be implemented in hardware or in software functional modules. The integrated modules may also be stored in a computer readable storage medium if implemented in the form of software functional modules and sold or used as a stand-alone product.
The above-mentioned storage medium may be a read-only memory, a magnetic disk or an optical disk, or the like.
In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
While embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the invention, and that variations, modifications, alternatives and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the invention.