Tutorial | HRT Analyzer — Transcript

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1. 0:02Welcome to Star Oddi's tutorial In this video we'll go over the use of the HRT Analyzer software.
2. 0:09It is a great tool that will help you  navigate, process and validate your ECG data.
3. 0:16By the end of this tutorial, you will know how to  upload, process and validate your data
4. 0:22and view the modified results. Let's dive in!
5. 0:27We'll begin by going over the software installation. If you've already installed it, feel free to skip to the next chapter.
6. 0:37Go to the Star Oddi website and click on the 'Software' button in the 'SUPPORT' menu.
7. 0:43You'll see all our software options here. Click on the HRT Analyzer to download it.
8. 0:50Once downloaded open the installation file and follow the installation steps.
9. 0:56Then, open the HRT Analyzer and start  working work with your data.
10. 1:01For additional help and guidance, you can open the User Manual by clicking on the Download User Manual button in the corner.
11. 1:12Next, we'll go over how to upload and  save the data.
12. 1:17First, set the source folder where the data you want to validate is stored.
13. 1:23Here I have an example folder. In the typical Mercury file structure, you have multiple files in the logger folder.
14. 1:32However, the HRT Analyzer software only works with DAT and HAT files, so you'll only see those files displayed.
15. 1:40The DAT file contains data such as the logger's heart rate and quality index, among other variables.
16. 1:50The HAT file contains raw ECG data. For instance, in this example, measurement number 2354 includes raw ECG data.
17. 2:03Here, I have plotted the first ECG record. The heart rate is calculated using the R-R interval of the ECG waveform
18. 2:12that is, the time elapsed between two successive R waves.
19. 2:19These are converted files based on what you have done inside Mercury, like quality index elimination.
20. 2:26You can find older conversion files inside the sequence number folder.
21. 2:33In this case, I have only the original file, which is marked with zero in the beginning.
22. 2:40However, if you've previously reconverted the data in Mercury, you'll see those files here as well.
23. 2:49Next, set the working folder where the modified data files will be saved. It can be the same folder as the source folder or a new one.
24. 3:00Finally, set the filter folder, which contains filters that are used to process the ECG records.
25. 3:08This folder should always be the Mercury filter folder.
26. 3:16Now, I should have some HAT files available.
27. 3:18I'll select the original file, with zero at the beginning. Then, I'll select the first recorded ECG and load that record.
28. 3:31Now we have selected data to work with, and we can start processing it
29. 3:36Once you have loaded the record, you can navigate the data.
30. 3:39Use these buttons to move between ECG records and save each record with this button.
31. 3:46Or, create hotkeys for faster use by pressing the question mark.
32. 3:51If you have the DAT file in the source folder, you'll see the logger calculated heart rate and quality index here.
33. 4:01This particular record shows a calculated heart rate of 36 and quality index of 0.
34. 4:08As you work with the data, you'll also see the computer and user-calculated heart rates,
35. 4:15heart rate variability and quality index.
36. 4:18You can process this data by pressing the 'Built in filters', and the software highlights the filter that you should be using.
37. 4:27After selecting a filter,  you process a single record or the entire file.
38. 4:39Here, you can see how the computer algorithm detected the QRS waveforms.
39. 4:44It assigns peaks to the biggest slope of the QRS waveforms, where the most significant difference is between two points, not necessarily on the absolute peaks.
40. 4:56The computer annotated data also gives us 36 bpm, but in addition, it calculates HRV, both the SDNN and RMSSD values.
41. 5:11The computer and logger should match, but older loggers might show slightly different heart rates and quality index.
42. 5:20On the right hand side, you can see the processed data after it has gone through the band pass filter,
43. 5:28the waveform can change significantly depending on the animal model and the filter file used.
44. 5:35Now that we have processed  the data, let's move on to validate each record.
45. 5:42You can manually annotate the record by pressing  the peaks of the QRS waveform to get an absolute detection.
46. 5:50You can see that it also gives 36 bpm and very similar heart rate variability values.
47. 5:57If I press 'S', I save the manually annotated peaks and can go to the next record by pressing 'D'.
48. 6:04For faster manual annotation, validate the computer annotation
49. 6:09and save them as your user's peaks by pressing 'S' without marking any peaks.
50. 6:16To add or reject peaks, make those changes and press 'S' again.
51. 6:23Here are some examples of ECG records that need adjustment.
52. 6:29This record has one erroneous peak that should be excluded.
53. 6:34To fix this, I press 'S', then exclude the peak, and press 'S' again to save the change.
54. 6:42In the next example, the filter has only selected one peak, while the other peaks were rejected.
55. 6:50This requires a manual annotation. I'll manually select each of the peaks.
56. 6:57The last peak isn't an obvious QRS waveform, but it follows the same rhythm as the others.
57. 7:03You can choose to either include or exclude it—it won't significantly affect the heart rate but it will impact the heart rate variability
58. 7:14Finally, in this example, the computer's annotation can be validated, and one extra peak is rejected.
59. 7:23Again, excluding this peak won't change the heart rate much, but it will have greater impact on the heart rate variability.
60. 7:34Now the data has been validated and regulated. Let's view the updated data.
61. 7:41You can save the changes to enhanced .DAT file either with bpm and quality index values set by the user
62. 7:50or calculated by the HRT Analyzer when the records are processed, by pressing these buttons.
63. 7:56Or you can use the files automatically saved inside the working folders. Those files only include the records with saved ECG.
64. 8:06The protobuf file is used by the analyzer to calculate data.
65. 8:11Other files can be opened with a text editor  Excel, R or other preferred software.
66. 8:19The CQI files include heart rate and quality index for user or pc-annotated records and can be compared to the RQI file from Mercury.
67. 8:31The UCL file combines all  information from the user, computer and logger.
68. 8:39Then there are three HRV files: one for user-annotated records one for computer-annotated data and one combining both
69. 8:49if user annotations exist, those records are placed instead of the computer-annotated records.
70. 8:57Check the user manual for further descriptions of these files.
71. 9:02I'll go over the user-pc HRV file, as it's  the most commonly used.
72. 9:10You can plot the heart rate and heart rate variability. Here you can see the plotted variables and the high spikes
73. 9:18in the heart rate variability plot. Those are probably erroneous values, and those records can be investigated further.
74. 9:26You can also see the average amplitude  and the number of QRS waveforms used for the calculations.
75. 9:38Thank you for watching this tutorial.
76. 9:41If you have any questions or need additional help please refer to the user manual or email us.