Ultrasonic diagnostic apparatus and method of retrieving and displaying heart function test period

The present invention provides an ultrasonic diagnostic apparatus including a bio-signal analyzing section sequentially acquiring a bio-signal from a bio-signal acquiring section over a plurality of cycles to evaluate stability of a heart function in one cycle between particular signal waveforms of the bio-signal and one cycle between particular signal waveforms adjacent to the one cycle between the particular signal waveforms, selecting the one cycle between the particular signal waveforms and one cycle between the particular signal waveforms adjacent to the one cycle between the particular signal waveforms as a test period for the heart function based on the content of the evaluation, and associating the selected test period with a time phase of the bio-signal.

TECHNICAL FIELD

The present invention relates to an ultrasonic diagnostic apparatus and a method of retrieving and displaying a heart function test period in which a test period in a bio-signal suitable for use in a heart function test is retrieved and then output and displayed on a display screen to improve the efficiency in the heart function test for an object.

BACKGROUND ART

Heart functions are closely correlated not only with electrocardiogram waveforms (electrocardiograms) but also with bio-signals periodically changing due to motions of a heart such as pulses, blood pressures, and heart sounds, so that those bio-signals are used to perform a heart function test. The hear function test involves displaying section images of organs with an ultrasonic diagnostic apparatus over several cycles of the periodically changing bio-signal and computing measurement data representing the hear functions such as the bloodstream state, bloodstream rate, annulus rate, atrium volume, and heart wall motions.

It is presumed that the heart function test should desirably be performed with a plurality of cycles of the bio-signal remaining stable. Thus, ultrasonic measurement data including ultrasonic image data is acquired in association with the changes of the bio-signal and is once stored in a storage section such as a cine memory. Then, for example, a tester retrieves the cycle in which the bio-signal is stable while seeing the bio-signal and the reproduced image of the ultrasonic measurement data, and sets the retrieved cycle to a test period to perform the heart function measurement.

In a case with arrhythmia having unstable pulses, the electrocardiogram waveforms stored in the cine memory are reproduced, and the tester advances frames one by one using an input unit to retrieve the period with stable pulses while seeing the electrocardiogram waveforms.

In Non-Patent document 1, time intervals (R-R time) between two adjacent R waves from one R wave (heart beat) to the next R wave are sequentially measured on the basis of electrocardiogram waveforms, and a tester manually retrieves with an input unit, as a conforming period, the period in which the ratio between two adjacent R-R times is approximately one, and specifies the R-R time immediately after the conforming period as a test period. The hear function measurement is performed in the test period. The measurement is shown to be valid as the measurement value in the case with arrhythmia.

According to the method described in Non-Patent document 1, however, the retrieval of the conforming period requires the tester to watch the displayed image to determine whether or not the ratio between the two adjacent R-R times falls within the allowable range to retrieve the conforming period while he manually reproduces the bio-signal with the input unit. This causes time and effort and a burden on the tester, and in addition, when the tester erroneously retrieves the conforming period, he may retrieve an inappropriate test period as a result.

On the other hand, Patent Document 1 has proposed that the waveforms from a certain R wave to the second earlier R wave are taken on the basis of the history of electrocardiogram waveforms, the difference between the two R-R times included therein is calculated, and when the time difference is equal to or lower than a preset threshold value, that period is evaluated as a conforming period in which pulses are stable.

PRIOR ART REFERENCES

Patent Literature

Non-Patent Literature 1: Tomotsugu Tabata, et al., Assessment of LV systolic function atrial fibrillation using an index of preceding cardiac cycles, Am J physiol Heart Circ Physiol 281: H573-H580, 2001

SUMMARY OF THE INVENTION

Problems that the Invention is to Solve

According to the method described in Patent Document 1, however, the difference between the time intervals of the plurality of conforming periods (evaluation value) for which the test period is specified is not output for display, so that the tester has difficulty in comparing the evaluations of the plurality of retrieved test periods and may not determine the reliability of the measurement data provided from the heart function measurement based on the bio-signal in one test period. As a result, the heart function measurement is performed again in the other test periods as a precaution. Thus, Patent Document 1 requires the heart function measurement again and has the unsolved problem in which the efficiency of the heart function test needs to be improved.

It is an object of the present invention to provide an ultrasonic diagnostic apparatus capable of efficiently performing a heart function test based on a bio-signal and a method of retrieving and displaying a heart function test period.

Means for Solving the Problems

To achieve the above object, the present invention includes a bio-signal analyzing section sequentially acquiring a bio-signal from a bio-signal acquiring section over a plurality of cycles to evaluate stability of a heart function in one cycle between particular signal waveforms of the bio-signal and one cycle between particular signal waveforms adjacent to the one cycle between the particular signal waveforms, selecting the one cycle between the particular signal waveforms and one cycle between the particular signal waveforms adjacent to the one cycle between the particular signal waveforms as a test period for the heart function based on the content of the evaluation, and associating the selected test period with a time phase of the bio-signal.

Advantage of the Invention

According to the present invention, the heart function test based on the bio-signal can be performed efficiently.

BEST MODE FOR CARRYING OUT THE INVENTION

Referring toFIG. 1showing a block schematic diagram, description is made of an ultrasonic diagnostic apparatus according to an embodiment of the present invention implementing a method of retrieving and displaying a heart function test period. As shown, an ultrasonic diagnostic apparatus1is formed to include an ultrasonic probe3, an ultrasonic transmitting/receiving section4, an ultrasonic image producing section5, a storage section6, an input section7, an output/display section8, a bio-signal acquiring section9, a bio-signal analyzing section10, a measuring and computing section11, a control section12, and a system bus13.

The ultrasonic probe3is formed to include a plurality of oscillators for transmitting and receiving ultrasonic to and from an object2which is an organ of interest. The ultrasonic probe3may be provided by using a scan method of a linear type, a convex type, and a sector type.

The ultrasonic transmitting/receiving section4receives information about the power and the timing of an ultrasonic signal to be transmitted and received from the control section12and controls the ultrasonic probe3such that a predetermined reflection echo signal is acquired. The ultrasonic transmitting/receiving section4processes and outputs the reflection echo signal received by the ultrasonic probe3to the ultrasonic image producing section5and the measuring and computing section11.

The ultrasonic image producing section5passes the reflection echo signal input from the ultrasonic transmitting/receiving section4through a phasing circuit and an amplifier circuit to process the signal in accordance with imaging settings provided by the control section12. The ultrasonic image producing section5produces ultrasonic images based on the shaped ultrasonic signal such as a section image of an organ of the object2, a bloodstream image and an bloodstream rate image based on the Doppler measurement, and an organ Doppler image, for example.

The storage section6stores ultrasonic measurement data including the ultrasonic image produced in the ultrasonic image producing section5, measurement data computed in the measuring and computing section11, and bio-signal data acquired in the bio-signal acquiring section9. The storage section6also stores a program for realizing the functions of the respective sections constituting the ultrasonic diagnostic apparatus1. For example, the storage section6stores a computation algorithm used in executing the signal analyzing section10and the measurement computing section11.

The input section7is an interface for a tester to perform various types of operations in the ultrasonic diagnostic apparatus1and includes an input device such as a keyboard, trackball, switch, and dial. For example, the input section7is used to perform measurement settings of an organ on an ultrasonic image displayed on a display screen of the output/display section8and to move the current time phase of a reproduced image and a test period. The output/display section8displays the bio-signal, the ultrasonic image, and the measurement data on the screen or outputs the measurement data in a measurement report.

The bio-signal acquiring section9acquires and converts the bio-signal of the object2into bio-signal data and stores the data in the storage section6. The bio-signal acquiring section9directly inputs the acquired bio-signal to the bio-signal analyzing section10or acquires and inputs the bio-signal from the storage section6to the bio-signal analyzing section10. Specifically, when the bio-signal analyzing section10is operated in real time, the bio-signal data is directly input from the bio-signal acquiring section9to the bio-signal analyzing section10. Although an electrocardiogram is a typical example of the bio-signal, the present invention is not limited thereto, and a heart sound diagram or a pulse signal can be used as long as the time intervals between heart beats can be retrieved in the bio-signal.

The bio-signal analyzing section10has the function of sequentially acquiring the bio-signal over a plurality of cycles from the bio-signal acquiring section9, evaluating the stability of heart functions in one cycle between particular signal waveforms of the bio-signal and one cycle between particular signal waveforms adjacent to the one cycle between the particular signal waveforms, selecting the one cycle between the particular signal waveforms and one cycle between the particular signal waveforms adjacent to the one cycle between the particular signal waveforms as a test period of the heart functions based on the evaluations, and associating the selected test period with the time phase of the bio-signal.

In other words, the bio-signal analyzing section10retrieves the heart beats in a preset number of successive periods (for example, two) based on the bio-signal data input from the bio-signal acquiring section9to compare whether or not the retrieved successive periods have equal heart beat data. The comparison is performed with the computation algorithm stored in the storage section6. The details are described later.

The measuring and computing section11determines through computation the measurement data representing the bloodstream rate, atrium volume, annulus motions, and heart wall motions based on the Doppler measurement and the ultrasonic measurement data of the organ Doppler relating to the heart functions. For example, the measuring and computing section11computes the measurement data such as the bloodstream rate in a region of interest (ROI) set with the input section7by using the computation algorithm stored in the storage section6. The measurement values resulting from the computation are stored in the storage section6and read out as required. The control section12is formed to include a CPU and the like and controls the overall ultrasonic diagnostic apparatus1. In the present embodiment, the control section12particularly controls the synchronization of a series of operations performed in the bio-signal acquiring section9, the bio-signal analyzing section10, the measuring and computing section11, and the output/display section8. The system bus13is a bus on which the data is passed between the respective processing units.

The method of retrieving and displaying the heart function test section characteristics of the present invention will hereinafter be described in individual embodiments. Although the following embodiments are described in conjunction with the use of an electrocardiogram signal as the bio-signal, it goes without saying that the present invention is not limited to the use of the electrocardiogram signal.

Embodiment 1 is an example in which electrocardiogram data to be analyzed is previously accumulated in the storage section6before analysis. This is an example of so-called off-line processing, andFIG. 2shows a flow chart of the processing. As shown inFIG. 2, electrocardiogram data is acquired by the bio-signal acquiring section9, the ultrasonic probe3is brought into contact with the object2to transmit and receive ultrasonic under predetermined imaging conditions to perform ultrasonic measurement, and the ultrasonic measurement data including the acquired ultrasonic image data and Doppler measurement data is stored in the storage section6(S101). At this point, for example, moving images including an electrocardiogram waveform diagram and an ultrasonic image are displayed on the display screen of the output/display section8.

Next, when the tester performs freeze operation with the input section7, the output of the images to the display screen by the output/display section8is stopped (S102). At this point, the storage section6has the accumulated ultrasonic measurement data and electrocardiogram data acquired at S102. Then, the bio-signal acquiring section9is activated to acquire the electrocardiogram data of a range to be analyzed from the electrocardiogram data stored in the storage section6(S103).

The bio-signal producing section8may be activated after the freeze or may be executed by pressing an electrocardiogram data analyzing button provided for the input section7.

Upon start of the operation, the bio-signal acquiring section9extracts the electrocardiogram data of the required time range from the electrocardiogram data accumulated in the storage section6. The range to be analyzed may be all the accumulated electrocardiogram data or only the period displayed as waveforms on the screen of the output/display section8, for example. The range of the electrocardiogram data to be analyzed can be narrowed to reduce the analyzing time to smooth the operation of the apparatus, thereby providing the effect of improving the test efficiency.

The electrocardiogram data read out from the storage section6by the bio-signal acquiring section9is input to the bio-signal analyzing section10to perform the analysis of the electrocardiogram data (S104). The analysis of the electrocardiogram data in the bio-signal analyzing section10is described with reference toFIG. 3. As shown inFIG. 3(a) andFIG. 3(b), R waves in the electrocardiogram waveform are set to particular signal waveforms. Each time the R wave is input, the bio-signal analyzing section10retrieves the time interval between that R wave and the previously input R wave. For example, as shown inFIG. 3(a), assuming that the electrocardiogram waveform is input in the order of R3, R2, then R1, the bio-signal analyzing section10determines a time interval R3-R2between R3and R2corresponding to one cycle of the electrocardiogram waveform and a time interval R2-R1between R2and R1corresponding to the adjacent one cycle of the electrocardiogram waveform. When a comparison between the two adjacent time intervals shows that they are approximately equal, the bio-signal analyzing section10assumes that the pulses are regular and stable, and retrieves those R-R periods as a conforming period. On the other hand, inFIG. 3(b), an interval R2-R1is shorter than an interval R3-R2, so that the bio-signal analyzing section10assumes that the pulses are irregular and unstable, and sets those periods as non-conforming periods.

The following three methods are contemplated as the specific methods of using the two adjacent time intervals R3-R2and R2-R1to evaluate the stability of the heart functions to select or retrieve the conforming period.

(1) As the ratio between the two adjacent time intervals R3-R2and R2-R1is closer to one, the stability evaluation value is higher.

FIG. 3(a) shows the example in which (R2-R1)/(R3-R2) is approximately one and the evaluation value of the stability is high.FIG. 3(b) shows the example in which (R2-R1)/(R3-R2)<<1 and the evaluation value of the stability is low. Thus, inFIG. 3(a), the R3-R2period and the R2-R1period are retrieved as the conforming periods. The period immediately after the conforming period R1is specified as a test period suitable for the heart function measurement. In this case, the ratio between the time intervals of the two R-R periods evaluated as the conforming periods is compared with a preset threshold value. The threshold value can be set as a range having the lower limit and upper limit such that the lower limit is 0.95 and the upper limit is 1.05, for example. The threshold value can be set by the tester using the input section7, or a standard value can be preset for the apparatus.

(2) As the absolute value of the difference between the two adjacent time intervals R3-R2and R2-R1is closer to zero, the stability evaluation value is higher.

FIG. 3(a) shows the example in which |(R3-R2)−(R2-R1)| is approximately zero and the evaluation proves high stability.FIG. 3(b) shows the example in which |(R3-R2)−(R2-R1)|>>0 and the evaluation proves low stability. While the threshold value for the evaluation is also set in this case, the threshold value is set to 50 ms or less, for example, since it represents the difference in time intervals.

(3) As the matching between the waveforms of the two adjacent R-R periods is higher, the evaluation value of the stability is higher.

In the example shown inFIG. 3, the matching between the R3-R2waveform and the R2-R1waveform is used as an evaluation criterion. The matching between the waveforms is evaluated not only with the correlation coefficient of both waveforms and but also by previously storing a normal waveform in the storage section6and performing pattern matching between the normal waveform and the R-R waveform. When the matching falls within a preset range of threshold values, that R-R period is retrieved as the conforming period.

Since the above evaluation methods (1) and (2) involve simple computation, they have the advantages such as short calculation times, smooth operation of the apparatus, and excellent operability of the apparatus. On the other hand, the evaluation method (3) can evaluate the stability of the electrocardiogram waveform more precisely than in the evaluations methods (1) and (2), but the method (3) requires a long time for the computation to result in less smooth operation of the apparatus.

The above evaluation methods (1), (2), and (3) have been described with the example in which the stability is evaluated on the basis of the difference between the two adjacent R-R periods and the like to retrieve the conforming period. It goes without saying that the present invention is not limited thereto and that the stability can be evaluated on the basis of three or more adjacent R-R periods to retrieve the conforming period. For example,FIG. 4(a) andFIG. 4(b) show examples in which three successive time intervals R4-R3, R3-R2, and R2-R1are used to evaluate the stability of the heart functions. In the example shown inFIG. 4(a), since the ratio or the difference between the three successive time intervals satisfies an evaluation threshold value or satisfies an evaluation threshold value for the matching between the waveforms of the three successive time intervals, the electrocardiogram cycle immediately after the last conforming period R1is specified as the test period. On the other hand, in the example shown inFIG. 4(b), since the time interval or the waveform between R4and R3is significantly different from those of the other two R-R intervals, those periods are not conforming periods. Thus, the electrocardiogram cycle immediately after the R2-R1interval cannot beset to the test period. Similar evaluation can be performed for four or more successive intervals. The number of the successive intervals can be set to a value by the tester using the input section7or a standard value can be preset for the apparatus.

According to the method of evaluating the test period suitable for the heart function measurement described above, the stable heart beats can be set selectively to be shorter or longer depending on the severity of the arrhythmia of the object to improve the usability of the apparatus.

The method of evaluating the conforming period described above is applied to the entire range of the electrocardiogram data acquired at step S103inFIG. 2. For each R-R period for which the computation is performed, the relevant information is stored in the storage section6such as the evaluation value of the ratio or the difference or the matching, the R-R time interval, and the serial number given to the specified test period.

Next, at step S105inFIG. 2, the output/display section8functions to display the electrocardiogram information of the test period and the preceding R-R periods involved in the evaluation as shown inFIG. 5.FIG. 5shows an example of a display screen201of the output/display section8immediately after the completion of step S104at which the electrocardiogram data is analyzed. As shown, the analysis of the electrocardiogram data is performed in the range of an electrocardiogram waveform204displayed on the screen.FIG. 5shows the example in which the number of successive R-R periods used for retrieving the conforming periods is set to two. An ultrasonic image202which is the section image of the heart is displayed on the display screen201. The ultrasonic image202is the section image of the heart at the position of a time phase bar203on the time axis displayed on the electrocardiogram waveform204. Thus, the time phase bar203represents the time phase of the currently reproduced ultrasonic image202on the electrocardiogram waveform. Instead of or together with the ultrasonic image202, the measurement value calculated in the measuring and computing section11or the Doppler waveform may be displayed.

Below the electrocardiogram waveform204, a range205of the time axis including two R-R periods evaluated as the conforming periods and the test period is displayed, and the time (ms) of each R-R period is displayed. The evaluation value of the stability is displayed at the R wave time phase at the beginning of the test period. For example, in the left half of the electrocardiogram waveform204, the time intervals of the two R-R periods serving as the conforming periods are 800 and 820, respectively. Thus, the ratio (evaluation value) thereof is approximately 0.98. The evaluation value is displayed as an evaluation value206above the R wave time phase at the beginning of the test period subsequent to the conforming periods. In an example shown in the right half of the electrocardiogram waveform204, the evaluation proves high stability of two adjacent R-R periods in the three successive periods. In this case, when the stability is evaluated with the set number equal to two, the two test periods are specified and the two evaluation values are calculated in the conforming periods of the first two periods and the conforming periods of the second two periods. Thus,FIG. 5shows the evaluation values206of 0.99 and 1.02 at the two positions of the R waves. In addition, the number of all the R-R periods (R-R8)207retrieved within the range of the electrocardiogram data acquired at step S103is displayed. Serial numbers208are displayed at the positions of the R wave time phases at the beginnings of the test periods.

The test periods are highlighted by solid lines and the other R-R periods are displayed by broken lines to allow visual recognition. The highlighting of the test periods may be performed by changing the color of or blinking the electrocardiogram waveform in the test periods. For example, although the range205of the time axis of the conforming periods is shown by double lines inFIG. 5, the double lines may be shown in light color and the range205of the test period may be highlighted in dark color. Alternatively, the range205of the test period may be blinked. When the time phase bar203representing the time phase of the reproduced ultrasonic image202is present outside the test period as in the example ofFIG. 5, the ultrasonic image202in that time phase is not appropriate for the analysis of the hear functions. Thus, the display may be more apparent to the tester by coloring or blinking the frame202of the image, shading or darkening the ultrasonic image202. When the time phase bar203is present outside the conforming periods and the test periods, the display may be more apparent to the tester similarly by coloring or blinking the frame202of the image.

Next, other display examples of the display screen according to Embodiment 1 are shown inFIG. 6andFIG. 7.FIG. 6shows a display screen201immediately after the completion of the electrocardiogram data analysis at S104. The example inFIG. 6shows the entire range of the electrocardiogram waveform204in which the electrocardiogram data to be analyzed is displayed on the screen, and illustrates the case in which the set number of the successive conforming periods for evaluating the stability is set to three.FIG. 6shows the display similar to that inFIG. 5, and the time intervals between R-R periods are measured and displayed as 810, 820, and 830 (ms) in order. The ratios between the time intervals of the two adjacent R-R periods are 0.99 and 0.99 in order. Thus, the evaluation value 0.99 is displayed as an evaluation value206above the last R wave of the two adjacent R-R waves. In the example ofFIG. 6, the three successive R-R periods satisfying the stability evaluation condition continue, so that the two test periods are retrieved and the evaluation value 1.02 is displayed as the evaluation value206.

In the example of the display shown inFIG. 7, the information displayed in addition to the electrocardiogram waveform is minimized to improve visual recognition. Since the examples of the display screen shown inFIG. 5andFIG. 6display much information around the electrocardiogram waveform, some testers have difficulty in finding important information. In the present example, when the time phase bar203is located in any of the two R-R periods for which the stability is evaluated, the range205of those R-R periods is highlighted. The evaluation value206and the R-R time209are displayed in a different region (right region in the shown example) not around the electrocardiogram waveform. When the time phase bar203is moved to any of the two R-R periods for which the stability is evaluated, for example by using a track ball of the input section7, the evaluation value206and the R-R time209are overwritten in the heart beat to which the movement is made. In addition, the display of the range205is also moved and highlighted.

According to Embodiment 1 described above, the limited electrocardiogram data to be analyzed is acquired, and the calculation is performed on that data for retrieving the test period, so that the amount of the calculation can be reduced to reduce the load on the apparatus. This can smooth the operation of the apparatus to improve the test efficiency.

Since the retrieved test periods are highlighted, the tester can have access easily.

When the possibly suitable test periods are ranked on the basis of the evaluation values and are displayed in different colors in accordance with the ranks, the usability is further improved.

Since the tester can select and set the evaluation conditions such as the ratio and the difference between the adjacent R-R periods and the matching between the waveform patterns in the electrocardiogram data analysis, the conforming period for retrieving the test period can be appropriately retrieved. As a result, the conforming period and the test period appropriate for the symptoms can be retrieved, so that the excellent usability is achieved.

In addition, since the number of the adjacent successive R-R periods for which the stability is evaluated can be changed, the retrieval of the conforming period can be performed depending on the severity of arrhythmia, thereby improving the usability of the apparatus.

When the display screen is switched between the display of various information of the electrocardiogram on the electrocardiogram waveform and the display of the information in a different region on the screen rather than the electrocardiogram waveform, detailed analysis and simple analysis can be performed individually to allow the selection fit for the use of the tester.

Embodiment 2 is an example in which electrocardiogram data to be analyzed is successively stored in the storage section6and is analyzed at the same time. This is the example of so-called real-time processing, andFIG. 8shows a flow chart of the processing. In the present embodiment, similarly to Embodiment 1, at step S201, the electrocardiogram data is acquired by the bio-signal acquiring section9, and the tester brings the ultrasonic probe3into contact with the object2, transmits ultrasonic under predetermined imaging conditions to perform the ultrasonic test, and stores the acquired electrocardiogram waveform diagram, ultrasonic image data, Doppler measurement data and the like in the storage section6, and the moving image of the ultrasonic image is displayed on the display screen of the output/display section8. In this state, the function of the bio-signal analyzing section10is valid through the operation of the input section7by the tester. Description is made assuming the set number of adjacent successive R-R periods serving as the condition for retrieving the conforming periods is two.

First, the bio-signal acquiring section9acquires the electrocardiogram data newly stored in the storage section6and inputs the acquired data to the bio-signal analyzing section10(S202). The bio-signal analyzing section10analyzes the sequentially input electrocardiogram data (S203). Specifically, the bio-signal analyzing section10performs an evaluation to determine whether or not the ratio or the difference between the time interval of the latest two R-R periods stored in the storage section6or the matching between the waveform patterns in those R-R periods satisfies a threshold value. When the threshold value is satisfied as a result of the evaluation, those R-R periods are set to the conforming periods to perform retrieval. Similarly to Embodiment 1, various types of information relating to the electrocardiogram waveform are displayed on the display screen201as shown inFIG. 5(S204). When the next R wave is retrieved and the new R-R period is stored in the storage section6, the control returns to step S202to repeat the same processing (S205). Then, when a freeze instruction is input through the input section7, the storage of the new electrocardiogram data in the storage section6is stopped to end the processing of the bio-signal analyzing section10(S206).

FIG. 9illustrates the operation in Embodiment 2 represented on a time axis and shows changes over time of the electrocardiogram waveform and relating information displayed on the screen.FIG. 9(a) shows the point in time at which two R-R periods have been stored in the storage section6after the start of the acquisition of the electrocardiogram data. At this point, the electrocardiogram data is acquired from the storage section6by the bio-signal acquiring section9and is input to the bio-signal analyzing section10. The bio-signal analyzing section10analyzes the input two R-R periods and performs an evaluation to determine that the two R-R periods do not have the same electrocardiogram waveform. Thus, the electrocardiogram waveform displayed on the display screen is not highlighted or the electrocardiogram information is not displayed. The number of R-R periods (R-R2)207is displayed.

FIG. 9(b) shows the point in time at which the third R-R period has been stored in the storage section6after the start of the acquisition of the electrocardiogram data. At this point, the new third R-R period is input to the bio-signal analyzing section10through the bio-signal acquiring section9. The bio-signal analyzing section10analyzes the newest R-R period data and the preceding R-R period data and performs an evaluation to determine whether or not the second and third R-R periods are conforming periods. In the example ofFIG. 9(b), the evaluation proves that the second and third R-R periods are not conforming periods. Thus, the electrocardiogram waveform is not highlighted or the electrocardiogram information is not displayed.

FIG. 9(c) shows the point in time at which the fourth R-R period has been stored in the storage section6after the start of the acquisition of the electrocardiogram data. At this point, the new fourth R-R period is input to the bio-signal analyzing section10through the bio-signal acquiring section9. The bio-signal analyzing section10analyzes the newest R-R period data and the preceding R-R period data and performs an evaluation to determine whether or not the third and fourth R-R periods are conforming periods. In this example, the newest R-R period and the preceding R-R period are the same and two successive periods, so that those R-R periods are evaluated as the conforming periods. Thus, the time intervals and ranges205of the R-R periods, the evaluation value206, and the serial number208are displayed on the display image. At the same time, the electrocardiogram waveform is highlighted.

FIG. 9(d) shows the point in time at which the fifth R-R period has been stored in the storage section6after the start of the acquisition of the electrocardiogram data. At this point, the new fifth R-R period is input to the bio-signal analyzing section10through the bio-signal acquiring section9. The bio-signal analyzing section10analyzes the newest R-R period data and the preceding R-R period data and performs an evaluation to determine whether or not the fourth and fifth R-R periods are conforming periods. In this example, the newest R-R period and the preceding R-R period are the same and two successive periods, so that those R-R periods are evaluated as the conforming periods. Thus, the time intervals and ranges205of the R-R periods, the evaluation values206, and the serial numbers208are displayed on the display image. At the same time, the electrocardiogram waveform is highlighted.

When freeze is performed at step S206, the acquisition of various types of information in the ultrasonic diagnostic apparatus can be stopped, and after the stop, display similar to that in Embodiment 1 can be performed.

According to Embodiment 2, since the R-R period is stored in the storage section6with each heart beat, the R-R periods are sequentially processed and the results are displayed on the display screen of the output/display section8in real time.

Since the information about the electrocardiogram waveform including the results of the evaluation of the respective R-R periods is stored in the storage section6, the tester can access the previous data, for example through the operation of the track ball of the input section7, and the processing similar to that in Embodiment 1 can be performed.

As described above, according to the present embodiment, the R-R period data taken in real time by the storage section6can be acquired to perform the evaluation to determine immediately whether or not the set number of adjacent R-R periods are conforming periods. In other words, while the ultrasonic image is displayed, the conforming period suitable for the heart function measurement can be retrieved in real time to specify the test period. The freeze is performed at the time when the test period is specified, which allows the tester to easily access the heart beat cycle appropriate for the heart function measurement to perform the measurement processing. This can result in the improved efficiency of the test. Since the analyzed electrocardiogram data is stored in the storage section6, the tester can also access the heart beat cycle of the past.

Embodiment 3 is characterized in that a series of data for electrocardiographically analyzing functions stored in the storage section6is reproduced by jumping to a specified test period. In other words, Embodiment 3 is characterized by having the function of capable of access only to the test period specified in Embodiments 1 and 2 and stored in the storage section6and relates to a method of use after the completion of the processing in Embodiments 1 and 2.

In general, when display of the ultrasonic image in a desired time phase on the screen is desired, the tester manipulates, for example the track ball of the input section7, to display the images stored in the storage section6one by one for searching while checking the images. Embodiment 3 is characterized in that, since the time phase of the data for electrocardiographically analyzing the functions useful in the heart function measurement is the time phase in the test period, the direct access to the test period is allowed without burdensome searching. In Embodiments 1 and 2, the test periods are given the serial numbers and stored in the storage section6. In contrast, in the present embodiment, the direct jumping of the time phase to the test period enables the efficient access to the desired test period.

FIG. 10shows an example of the display image of the data for electrocardiographically analyzing the functions in the present embodiment. As shown, a jump button210for jumping the time phase bar is provided on the screen, for example. A rightward arrow of the button210is set to perform a rightward jump (to an advanced time phase) from the current time phase, and a leftward arrow is set to perform a leftward jump (to a past time phase) from the current time phase. For example, when the current time phase is located at the position of a time phase bar211, selection and pressing of the leftward arrow of the jump button210causes jumping from the current time phase to the past R wave time phase in the first test period having the first serial number and moves the time phase bar212to that time phase position. This changes the ultrasonic image202into an image at the time phase of the time phase bar212. Although not shown, Doppler measurement values and the like can be displayed at the time phase of the time phase bar212. In contrast, selection and pressing of the rightward arrow of the jump button210causes jumping of the time phase bar213from the current time phase to the advanced R wave time phase in the test period having the second serial number. When the rightward arrow of the jump button210is again selected and pressed, further advancement is made to cause jumping of the time phase bar214to the R wave time phase in the test period having the third serial number.

A downward arrow of the jump button210is set to move the time phase bar in the order of the evaluation value206. When the downward arrow is pressed once, the test period having the higher evaluation value206can be switched to the test periods having the lower evaluation values in descending order to jump to a desired test period.

Since the serial number is given to the test period, the serial number of the test period to which the jumping is to be performed is input through the input section7to allow jumping to the R wave time phase in the test period having the input serial number.

Instead of the jump button210, the track ball provided for the input section7can be used. In this case, setting is performed such that rotation of the track ball to the left causes jumping to the past R wave time phase in the test period and rotation of the track ball to the right causes jumping to the advanced R wave time phase in the test period. The present invention is not limited to the track ball, and any input device can be used as long as the position can be specified.

According to Embodiment 3 described above, only the R wave time phase in the test period can be moved, so that the tester can easily jump to access the desired test period without searching for the desired test period while checking the image. Since the jumping can be made in descending order of evaluation value, the tester can easily access the test period associated with the conforming period having the highest evaluation value. As a result, immediate transition can be made to the measurement operation or the like in the desired test period to contribute to the improvement of the test efficiency.

Embodiment 4 is an example which involves removing data for measuring heart functions, which is electrocardiogram data and ultrasonic image data other than those in the conforming periods and the test periods retrieved in Embodiments 1 and 2, to perform edits to provide only the required heart function measurement data.FIG. 11shows a flow chart of the present embodiment. InFIG. 11, steps S401to S403are identical to steps S102to S104in Embodiment 1. In the present embodiment, after the completion of the analysis of the electrocardiogram data at step S403, the electrocardiogram data and the ultrasonic image data are edited and that data is displayed at step S405.

FIG. 12shows an example of the display image in the present embodiment.FIG. 12shows the data for measuring the heart functions edited by cutting the portion not corresponding to any conforming period or any test period inFIG. 7and combining the portions before and after the cut portion. Specifically, the R-R period at the fourth beat inFIG. 7is removed and the portions before and after that period are combined. The ultrasonic image data is also provided by removing that R-R period and combining the portions before and after that removed portion.

Instead ofFIG. 12, when the data for measuring the heart functions is reproduced without cutting the portion not corresponding to any conforming period or any test period, the data of the portion not corresponding to any conforming period or any test period can be assumed to be absent and can be skipped in the reproduction.

As described above, according to Embodiment 4, the data not relating to any conforming period or any test period, that is, the unnecessary data in the test of arrhythmia is removed or skipped out of the acquired data, so that the immediate access can be made to the target test period. Since the unnecessary data is removed, only the useful data is taken into the memory to improve the efficiency of data collection. Thus, immediate transition can be made to the measurement operation or the like in the desired test period, so that the test efficiency is improved.

DESCRIPTION OF REFERENCE NUMERALS AND SIGNS