Saturday, January 11, 2025

MY SCRATCH POST — For Testing things out (1-7.1-2025)-KG


This is the LINK I am currently using for iframe

<iframe width="600" height="550" frameborder="0" scrolling="no" src="https://1drv.ms/x/c/2a6722bfdf99e002/IQTiMq1KWkRpToL2ePrp9vNrAb6Xufq-vmjaELWxEcrB7fE?em=2&wdAllowInteractivity=False&AllowTyping=True&wdHideGridlines=True&wdHideHeaders=True&wdDownloadButton=True&wdInConfigurator=True&wdInConfigurator=True"></iframe>


THIS IS OLD !!!!
<iframe width="600" height="550" frameborder="0" scrolling="no" src="https://onedrive.live.com/embed?resid=1697A7711DCFBCD6%21115&authkey=%21AJ6egwkNxOavSAo&em=2&wdAllowInteractivity=False&AllowTyping=True&wdHideGridlines=True&wdHideHeaders=True&wdDownloadButton=True&wdInConfigurator=True&wdInConfigurator=True"></iframe>


This is the original link — but the size is too small !!!!
<iframe width="402" height="346" frameborder="0" scrolling="no" src="https://onedrive.live.com/embed/resid=1697A7711DCFBCD6%21115&authkey=%21AJ6egwkNxOavSAo&em=2&wdAllowInteractivity=False&AllowTyping=True&wdHideGridlines=True&wdHideHeaders=True&wdDownloadButton=True&wdInConfigurator=True&wdInConfigurator=True"></iframe>







<iframe width="402" height="346" frameborder="0" scrolling="no" src="https://onedrive.live.com/embed?resid=1697A7711DCFBCD6%21115&authkey=%21AJ6egwkNxOavSAo&em=2&wdAllowInteractivity=False&AllowTyping=True&wdHideGridlines=True&wdHideHeaders=True&wdDownloadButton=True&wdInConfigurator=True&wdInConfigurator=True"></iframe>







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This is the link from my Google Drive (1/11/2025)



This is the link for direct use of Arron's QTc Calculator —

Below is the link to download the Excel file onto your computer.
  • XXXXX
This is the link from my Google Drive




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https://docs.google.com/spreadsheets/d/1I_xK2smhRpvwMTQKptEOI0EWknek9X8h/edit?usp=sharing&ouid=118270705448349878620&rtpof=true&sd=trueaction=embedview


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This on-line QT calculator that we link to below was created by Arron Pearce. It is a work in progress — as Arron continues anticipates making it even more user friendly. But in the meantime — Try it out!

Click on the link:
this is the new link that I used ...
https://docs.google.com/spreadsheets/d/1-f0ubyK_sfShUnZfNvNSg1OZzAZ_DJHt/edit?gid=714250249#gid=714250249

NOTE: This calculator works on an Excel spreadsheet. So after you click on the above link — You may need to download this calculator in Excel format.


Figure-1: Depending on your browser and computer — after clicking on the above link — you should get a worksheet looking something like this.
— Click on File.




Figure-2: After clicking on File — Click on Download in the menu.




Figure-3: Download the Microsoft Excel ( .xlxs ) format. And now when you open the downloaded Excel file on your computer — it should be easy to enter the heart rate and QT interval that you measure to instantly see QTc calculations in each of the 5 methods shown.
= = = = = 
For the modified QTc (when the QRS is wide) — Remember that QRS duration is in milliseconds (ie, a wide QRS = 0.15 second = 150 ms).
— The Rautaharju QTc calculation comes up immediately.
— To get the Bogossian QTc value, you'll need to enter the modified QT value into the QTc calculator on the left side of the page.


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Grauer: The fact that you will see slightly different values in the above QTc calculator conveys the lack of universal agree on QTc calculation at different heart rates. That said — 4 of the 5 methods are generally quite close to each other (You might mentally take an average of those readings for your value).
  • In our experience — We find the Bazett method potentially problematic, in that it tends to overestimate the QTc for faster heart rates — and underestimate the QTc for slower heart rates.


https://docs.google.com/spreadsheets/d/1GomwAh9kl40Z_wRK7Qsbwu9ilCsvrKCkjeObI93JDXw/edit?gid=718843857#gid=718843857



https://docs.google.com/spreadsheets/d/1GomwAh9kl40Z_wRK7Qsbwu9ilCsvrKCkjeObI93JDXw/edit?gid=718843857#gid=718843857

(https://x.com/arron_pearce_)





QUESTIONS:
  • How to interpret today’s initial rhythm? (shown in Figure-1).
  • Why is the QRS wide? 

Figure-1: The initial ECG in today's case (obtained prior to elective electrical cardioversion).


LINK for QTc Calculator (1-7.21-2025)-KG




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Smith-Modified Sgarbossa Rule for Diagnosis of STEMI in the Presence of Left Bundle Branch Block




New 4-variable Formula to Differentiate Normal Variant ST Segment Elevation in V2-V4 (Early Repolarization) from Subtle Left Anterior Descending Coronary Occlusion


This is the original paper on the 3-variable formula: 

Smith SW et al. Electrocardiographic Differentiation of Early Repolarization From Subtle Anterior ST-Segment Elevation Myocardial Infarction. Annals of Emergency Medicine June 2012.

We subsequently published the 4-variable formula:

Driver and Smith. A new 4-variable formula to differentiate normal variant ST segment elevation in V2-V4 (early repolarization) from subtle left anterior descending coronary occlusion - Adding QRS amplitude of V2 improves the model.  Journal of Electrocardiology.

This formula is more sensitive and specific than the old 3-variable formula, which I have deleted.

Both were externally validated here:



I recommend this primarily as a means of recognizing otherwise unrecognized LAD occlusion.

Do not let a value below the cutoff dissuade you if you think the diagnosis is LAD occlusion.

In other words, sensitivity is much more important than specificity

It is critical to use it only when the differential is subtle LAD occlusion vs. early repol. Thus, there must be ST Elevation of at least 1 mm. If there is LVH, it may not apply. If there are features that make LAD occlusion obvious (inferior or anterior ST depression, convexity, terminal QRS distortion, Q-waves), then the equation MAY NOT apply. These kinds of cases were excluded from the study as obvious anterior STEMI.


--QTc is the computer measurement. 
--RAV4 = R-wave amplitude, in mm, in lead V4. 
--ST elevation (STE) is measured at 60 milliseconds after the J-point, relative to the PR segment, in millimeters.

--QRSV2 is the entire QRS amplitude in lead V2 (both R- and S-waves).

(1.062 x STE at 60 ms after the J-point in V3 in mm) + (0.052 x computerized QTc) - (0.151 x QRSV2) - (0.268 x R-wave Amplitude in V4 in mm).

A value greater than 18.2 is quite sensitive and specific for LAD occlusion. 

There is a free iPhone app: "SubtleSTEMI"
There is a free Android app: "ECG SMITH"
Or go to www.mdcalc.com: https://www.mdcalc.com/subtle-anterior-stemi-calculator-4-variable









Simplified 4 Variable Formula (using raw QT, in mm, instead of QTc):

There is also a simplified formula developed by Dr. Emre Aslanger, based on the original formula and published in the American Journal of Cardiology in 2018; 122(8):1303-1309. The benefit of the new formula is that it is independent of any QT Correction, which would depend on the 4 different QT correction formulas. Also, this formula uses the QT in millimeters, not in milliseconds!

Here it is: (RAV4 + QRSV2) - [(QT in mm) + STE60V3); a value < 12 is indicative of LAD occlusion.

The area under the curve for this formula was 0.963, with sens, spec, and acc of 87%, 92%, and 90%









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