Wall motion analyzer

Abstract

A system and method for real-time quantitative analysis of heart wall motion is provided. A Doppler imaging system is used to monitor the movement of a heart, or other organ. A B-mode reference image of the target organ is made and then a region-of-interest is defined through the use of a gate. Then pulsed wave spectral tissue Doppler data of the region-of-interest is formed and used to determine the velocity of a region of the target organ. The system may be used for determining appropriate biventricular pacemaker settings for patients suffering from heart disease.

1 . A quantitative method for measuring tissue movement comprising:
 operating a Doppler imaging system to form a B-mode reference image of moving tissue;   forming a first plurality of gates along a first spectral Doppler line to define a first region of interest of the cardiac tissue;   forming a second plurality of gates along a second spectral Doppler line to define a second region of cardiac tissue;   forming pulsed wave spectral tissue Doppler data of the region of cardiac tissue; and   determining displacement of the cardiac tissue during a cardiac cycle.   
     
     
         2 . The method of  claim 1  further comprising forming a Doppler image of the tissue, and forming the first plurality of gates using the tissue Doppler image. 
     
     
         3 . The method of  claim 1  further comprising measuring displacement of a septal wall and lateral free wall of the heart as a function of time for at least a cardiac cycle. 
     
     
         4 . The method of  claim 1  further comprising displaying simultaneously a displacement of a septal wall and lateral wall of a heart as a function of time for at least a cardiac cycle. 
     
     
         5 . The method of  claim 1  wherein the step of forming the gates comprise forming at least two pulsed wave spectral Doppler lines in an single image frame to defining the region of interest. 
     
     
         6 . The method of  claim 5  further comprising determining an ejection fraction of a heart. 
     
     
         7 . The method of  claim 1  wherein the first region comprises a septal wall of a heart and the second region comprises a lateral wall of the heart. 
     
     
         8 . The method of  claim 6  further comprising using automatic border detection to measure tissue movement. 
     
     
         9 . The method of  claim 1  further comprising triggering an image capture using an EKG signal. 
     
     
         10 . The method of  claim 1  further comprising determining a directional value to indicate a direction of tissue displacement. 
     
     
         11 . The method of  claim 1  further comprising providing an apical image of a heart. 
     
     
         12 . The method of  claim 1  further comprising providing a short axis view of a heart. 
     
     
         13 . The method of  claim 1  further comprising determining a strain rate of tissue within the region of interest. 
     
     
         14 . The method of  claim 6  further comprising averaging the multiple-gate to detect global displacement of a septal wall of a heart and global displacement of a left free wall of the heart. 
     
     
         15 . The method of  claim 1  further comprising time integrating the pulsed wave spectral Doppler data to determine displacement of tissue within the region of interest. 
     
     
         16 . The method of  claim 14  further comprising measuring dysynchronous ventricular movement of the left ventricle of the heart. 
     
     
         17 . The method of  claim 12  further comprising displaying a B-mode image and simultaneously displaying displacement of an interventricular septal wall and a left free wall of a heart as a function of time for at least a cardiac cycle to visualize dysynchronous ventricular movement of the heart. 
     
     
         18 . The method of  claim 12  further comprising gold standard image set to guide the echocardiography imaging operations and to facilitate obtaining the quantitative data representative of heart wall motion. 
     
     
         19 . A quantitative method for measuring tissue movement by operating an echocardiography imaging system to determine a displacement of tissue, the method comprising:
 forming a sequence of B-mode reference images of moving tissue;   using automatic border detection to detect tissue movement; and   determining displacement of the tissue within the region of interest.   
     
     
         20 . The method of  claim 19  wherein the step of using automatic border detection further comprises using a B-mode image and a motion compensated block search process, each block comprising a plurality of pixels of the image. 
     
     
         21 . The method of  claim 20  wherein each block has a size in a range of 3×3 pixels to 31×31 pixels. 
     
     
         22 . The method of  claim 20  wherein the step of using automatic border detection further comprises providing an intensity threshold sequence to determine wall tissue boundaries. 
     
     
         23 . The method of  claim 20  further comprising determining an intensity value by summing an intensity of each pixel in a block. 
     
     
         24 . The method of  claim 19  further comprising simultaneously measuring displacement of a septal wall and a left free wall of a heart as a function of time for at least one cardiac cycle. 
     
     
         25 . The method of  claim 19  further comprising determining phase angle of displacement of a septal wall and a left wall of a heart, determining relative delay movement between the septal wall and the left wall of the heart. 
     
     
         26 . The method of  claim 19  wherein B-mode imaging capturing is EKG triggered. 
     
     
         27 . The method of  claim 19  further comprising setting at least 5 anchor points on an image of a heart to define a search area for block matching. 
     
     
         28 . A method for providing operating parameters for a biventricular pacemaker comprising:
 performing an echocardiographic imaging process to provide quantitative data representative of heart wall motion; and   selecting a lead delay setting for a biventricular pacemaker using the quantitative data.   
     
     
         29 . The method of  claim 28  wherein the step of performing a Doppler imaging process includes forming a plurality of gates in a single image frame for the measurement of the lateral wall and septal wall of a heart. 
     
     
         30 . The method of  claim 28  further comprising forming pulsed wave spectral tissue Doppler data of the lateral wall and the septal wall. 
     
     
         31 . The method of  claim 28  wherein capture of the echocardiographic image is EKG trigger. 
     
     
         32 . The method of  claim 28  wherein the gates are formed using a plurality of spectral Doppler lines on single image frame of the heart. 
     
     
         33 . The method of  claim 28  further comprising determining phase angle of displacement of an interventricular septal wall and a left free wall of a heart, determining relative delay movement between the two walls. 
     
     
         34 . The method of  claim 28  further comprising performing a phase analysis of heart wall motion using automatic border tracking. 
     
     
         35 . A system for diagnostic ultrasound imaging of moving tissue comprising:
 an ultrasound image display; and   a processing system, operative to execute a processing sequence stored on a computer readable medium, the processing sequence generating pulsed wave spectral Doppler data of moving tissue within a plurality of gates positioned along a plurality of spectral Doppler lines of an image frame that determine a displacement of tissue.   
     
     
         36 . The system of  claim 35  further comprising a programming processor connected to the processing system that programs a pacemaker. 
     
     
         37 . The system of  claim 35  further comprising a Doppler processor. 
     
     
         38 . The system of  claim 35  wherein the processing sequence further comprises spectral lines defining gates within an image frame. 
     
     
         39 . The system of  claim 35  further comprising an external ultrasound probe. 
     
     
         40 . The system of  claim 35  further comprising an ultrasound probe insertable within a body lumen.