A 53 year old male, presented to the Emergency Department with palpitations.
His ECG showed a heart rate of 132.
Here is his ECG.
What is your diagnosis?
Why do you think so?
Discussion:
The theme for the above case is "Narrow-Complex REGULAR Tachycardia".
The common differential diagnosis of narrow complex regular tachycardia is: 1) Sinus tachycardia. 2) SVT. 3) Atrial Flutter with a fixed block.
For Sinus Tachycardia, you should see a clear single P wave before each complex. Here is an example:
For SVT, you wouldn't usually be able to see any clear P waves anywhere. Here is an example:
For Atrial Flutter, you would see more than one P wave before each complex. Here is an example:
I used to work with the above rules for a long time & things were going well till I met cases like the above one & which taught me a few tips that changed my way of looking at the ECGs completely.
What is really interesting in the above case is that if you apply the above rules, you will get it wrong!
Let's analysis the ECG:
If you have a quick look at our ECG, you might think that there are no P waves, & then your diagnosis will be SVT, which is NOT true.
If you have a closer look, you will notice some "Inverted P waves" before the complexes.
ECG Tip:
Our eyes are not trained for some reason to see the inverted P waves, & they automatically see them as inverted T waves or just ignore them, so when you think that there might be some inverted P waves there, flip the ECG paper upside down & you will be surprised with what you will see
Here we go,
SURPRISE!!
Doing this, all of a sudden you see 2 P waves before each complex, & if you map them out (like what you do with the complexes to check for regularity), they will map perfectly.
The Final Diagnosis:
This was the tip for this case. The final diagnosis is ATRIAL FLUTTER with a 2:1 block.
The patient was given B.B. which helped to slow the heart rate down & the flutter waves became more obvious, then he spontaneously self-cardioverted & was discharged home later after a period of observation for cardiology follow-up.
This was the first case of tachyarrhythmia cases that we will discuss over a few blogs.
I hope you find this useful.
Best of luck.
If these are 2 p wave , where is t wave ?
Hello! Thanks for case of tachycardia.It is atrial flutter with block 2:1.But atrial flutter hasn.t P wawes, it was big F wawes in the inferior leads and tops of big F wawes we can see in V1.