Abstract: A method for calculating coronary artery fractional flow reserve includes determining myocardial volume by extracting myocardial images; locating a coronary artery inlet and accurately segmenting coronary arteries; generating a grid model required for calculation by edge detection of coronary artery volume data; determining myocardial blood flow in a rest state and CFR by non-invasive measurement; calculating the total flow at the coronary artery inlet in a maximum hyperemia state; determining the flow in different blood vessels in the coronary artery tree in the maximum hyperemia state and then determining flow velocity V1 in the maximum hyperemia state; using V1 as the flow velocity at the coronary artery inlet and calculating a pressure drop ?P from the coronary artery inlet to a distal end of a coronary stenosis, and a mean intracoronary pressure Pd at the distal end of the stenosis Pd=Pa??P, and calculating fractional flow reserve.

Abstract: A method for calculating an index of microcirculatory resistance includes determining myocardial volume by extracting myocardial images; locating a coronary artery inlet and accurately segmenting coronary arteries; generating a grid model required for calculation; determining myocardial blood flow in a rest state and CFR; calculating total flow at the coronary artery inlet in a maximum hyperemia state; determining flow in different blood vessels in a coronary artery tree in the maximum hyperemia state and then determining a flow velocity V1 in the maximum hyperemia state; obtaining the average conduction time in the maximum hyperemia state Tmn, and calculating a pressure drop ?P from the coronary artery inlet to a distal end of a coronary artery stenosis, and a mean intracoronary pressure Pd at the distal end of the stenosis Pd=Pa??P, and calculating the index of microcirculatory resistance.

Abstract: Disclosed is a method for calculating fractional flow reserve, comprising: collecting a pressure at the coronary artery inlet of heart by a blood pressure sensor in real-time, and storing a pressure value in a data linked table; obtaining an angiographic time according to the angiographic image, finding out the corresponding data from data queues based on time index using the angiographic time as an index value, screening out stable pressure waveforms during multiple cycles, and obtaining an average pressure Pa; and obtaining a length of the segment of blood vessel from angiographic images of the two body positions, and obtaining a blood flow velocity V; calculating a pressure drop ?P for the segment of the blood vessel using the blood flow velocity V at the coronary artery inlet, and calculating a pressure Pd at the distal end of the blood vessel, and further calculating the angiographic fractional flow reserve.

Abstract: Disclosed is a method for calculating an instantaneous wave-free ratio based on a pressure sensor and angiogram images, comprising: acquiring pressures at the coronary artery ostium of heart by a blood pressure sensor in real-time, and storing the pressure values in a data linked table, and the data linked table being indexed by time and the time and real-time pressure being saved in the form of key-value pairs; finding out corresponding datas from the data queue based on time index using the angiography time as an index value, taking an average value of four wave-free pressure values as a wave-free pressure value Pa; obtaining a time Tn of an end phase of a diastolic period, namely of a wave-free period within one cycle according to the time index within the cycle; obtaining a length L of a segment of a blood vessel through angiogram images of two body positions, and obtaining a blood flow velocity V; calculating a pressure drop ?P and calculating a pressure Pd which at the distal end of the blood vessel as

Abstract: A method for calculating an index of microcirculatory resistance includes determining myocardial volume by extracting myocardial images; locating a coronary artery inlet and accurately segmenting coronary arteries; generating a grid model required for calculation; determining myocardial blood flow in a rest state and CFR; calculating total flow at the coronary artery inlet in a maximum hyperemia state; determining flow in different blood vessels in a coronary artery tree in the maximum hyperemia state and then determining a flow velocity V1 in the maximum hyperemia state; obtaining the average conduction time in the maximum hyperemia state Tmn, and calculating a pressure drop ?P from the coronary artery inlet to a distal end of a coronary artery stenosis, and a mean intracoronary pressure Pd at the distal end of the stenosis Pd=Pa??P, and calculating the index of microcirculatory resistance.

Abstract: A method for calculating coronary artery fractional flow reserve includes determining myocardial volume by extracting myocardial images; locating a coronary artery inlet and accurately segmenting coronary arteries; generating a grid model required for calculation by edge detection of coronary artery volume data; determining myocardial blood flow in a rest state and CFR by non-invasive measurement; calculating the total flow at the coronary artery inlet in a maximum hyperemia state; determining the flow in different blood vessels in the coronary artery tree in the maximum hyperemia state and then determining flow velocity V1 in the maximum hyperemia state; using V1 as the flow velocity at the coronary artery inlet and calculating a pressure drop ?P from the coronary artery inlet to a distal end of a coronary stenosis, and a mean intracoronary pressure Pd at the distal end of the stenosis Pd=Pa??P, and calculating fractional flow reserve.

Abstract: A coronary artery load detection method includes: (S1) obtaining the cross-sectional area of a reference cavity, and separately obtaining voltage values of a primary device at a location corresponding to the cross-sectional area of the reference cavity in a low frequency state and a high frequency state; (S2) separately obtaining voltage values of the primary device at the location of a bottom end or a top end of a to-be-detected object in the low frequency state and the high frequency state under the same current; (S3) driving the primary device to move at a constant speed, and obtaining a voltage value of the primary device during the movement in the low frequency state under the same current; and (S4) obtaining the cross-sectional area of each location of the to-be-detected object according to a preset fixed current value, the cross-sectional area of the cavity, and the obtained voltage values.

Abstract: A method, device and system for acquiring blood vessel evaluation parameters based on an angiographic image are provided. The method includes: acquiring a real-time pressure Pa at a coronary artery inlet in an angiographic state to obtaining a Pa-t pressure waveform in time domain; subjecting a segment of blood vessel of interest in a two-dimensional angiographic image of the coronary artery in the angiographic state to three-dimensional modeling to obtain a three-dimensional grid model for the blood vessel; acquiring a real-time blood flow velocity v of the three-dimensional grid model for the blood vessel to obtain a v-t velocity waveform in the time domain; obtaining a ?P-t pressure drop waveform in the time domain from the coronary artery inlet to a distal end of the coronary artery stenosis through Fourier transform and the inverse Fourier transform; acquiring the coronary artery blood vessel evaluation parameters in the angiographic state.

Abstract: Disclosed is a method for calculating fractional flow reserve, comprising: collecting a pressure at the coronary artery inlet of heart by a blood pressure sensor in real-time, and storing a pressure value in a data linked table; obtaining an angiographic time according to the angiographic image, finding out the corresponding data from data queues based on time index using the angiographic time as an index value, screening out stable pressure waveforms during multiple cycles, and obtaining an average pressure Pa; and obtaining a length of the segment of blood vessel from angiographic images of the two body positions, and obtaining a blood flow velocity V; calculating a pressure drop ?P for the segment of the blood vessel using the blood flow velocity V at the coronary artery inlet, and calculating a pressure Pd at the distal end of the blood vessel, and further calculating the angiographic fractional flow reserve.

Abstract: A coronary artery load detection method includes: (S1) obtaining the cross-sectional area of a reference cavity, and separately obtaining voltage values of a primary device at a location corresponding to the cross-sectional area of the reference cavity in a low frequency state and a high frequency state; (S2) separately obtaining voltage values of the primary device at the location of a bottom end or a top end of a to-be-detected object in the low frequency state and the high frequency state under the same current; (S3) driving the primary device to move at a constant speed, and obtaining a voltage value of the primary device during the movement in the low frequency state under the same current; and (S4) obtaining the cross-sectional area of each location of the to-be-detected object according to a preset fixed current value, the cross-sectional area of the cavity, and the obtained voltage values.