Submitted by Dr A Röschl on Fri, 11/15/2024 - 01:29
Especially in the social media, one sees again and again similar EKGS like the one shown here with the question: What type of AV block is present here? 2nd degree AVB block type I (Wenckebach) or type II (Mobitz)? It is neither one nor the other!
Here, a PAC can be seen under the blue arrow, which is not conduced because the AV node is still refractory (the refractory period of the AV node depends on the preceding heart rate). Therefore, it is not an AV block, but a physiologically non conducted PAC.
Submitted by Dr A Röschl on Fri, 11/15/2024 - 01:17
This ECG comes from Germany, where unfortunately recording is still often done at 50 mm/s. Nevertheless, I believe that you can easily recognize the important changes in this ECG, even if you are not familiar with this recording format. The first two beats are the limb leads, the other beats are the precordial leads. The explanation of the visible ECG changes can be found in the 2nd diagram
Submitted by Dr A Röschl on Fri, 11/15/2024 - 01:06
It is not uncommon for several different abnormal changes to occur simultaneously in an ECG, as in this Holter ECG strip. The explanation of the visible ECG changes can be found in the 2nd image
Submitted by Dr A Röschl on Tue, 11/12/2024 - 02:29
The answer to the question is relatively simple. A premature atrial contraction (PAC) is usually characterized by the occurrence of a premature P wave. If the premature P wave is conducted, it is followed by a premature QRS complex. A premature VENTRICULAR contraction (PVC) is a premature beat from the ventricles with a wide QRS complex. A PVC will not have a P wave ASSOCIATED with it. There may be NO P wave before the QRS, or there may be an UNRELATED P wave present. The sinus P wave may be present if the PVC occurs just after the P, but before a normal QRS can result.
Submitted by Dr A Röschl on Tue, 11/12/2024 - 01:47
Sometimes you see an ECG and feel overwhelmed at first. This ECG rhythm strip is challenging at first glance. However, if you take a systematic approach to the analysis, it is usually possible to decipher the case.
The solution refers to the numbers in the second ECG:
Beats 1 and 3 are sinus
Beat 2 is a PVC
Beats 4 and 5 are a PVC couplet; the second one has managed to conduct retrogradely and produce a P wave, which resets the sinus node.
Beat 6 is a sinus P Wave with a junctional escape beat just after it (not conducted)
Beat 7 is a PVC
Submitted by Dr A Röschl on Mon, 09/23/2024 - 03:04
Unfortunately, I can't remember who the author of this ECG is. Perhaps he/she will get in touch with me. However, the ECG is very nice (despite the less than optimal recording quality) and that's why I want to post it. I don't know the history.
In the first section of the ECG we see coarse fibrillation waves and QRS complexes with very different RR intervals, which is why this is atrial fibrillation. It is not atrial flutter because the fibrillation waves are of different size and polarity (depending on the lead) and the intervals between the atrial actions are irregular.
Submitted by Dr A Röschl on Mon, 09/23/2024 - 02:51
Extract from a Holter ECG, 2 continuous strips, recorded at 25 mm/s. At the top you can see a broad complex tachycardia without recognizable P waves, which ends spontaneously after 2 beats in the lower section. This is a ventricular tachycardia (VT). The very first beat in the 1st strip is most probably a fusion beat. After the end of the VT in the 2nd strip, a narrow QRS complex appears, here you can also recognize that atrial fibrillation is present.
Submitted by Dr A Röschl on Sun, 08/25/2024 - 02:04
Sometimes you see an ECG strip, look at it and then put it away again with the thought: I don't understand this. But if you take your time and analyze the ECG systematically, you will usually come to a good result. This is an example of such an ECG (certainly not the most difficult). The explanation is shown in the 2nd picture.
Submitted by Dr A Röschl on Tue, 07/30/2024 - 03:26
The ECG shows an example of a patient with bradycardia/tachycardia syndrome (also called sick sinus syndrome). Initially, a sinus rhythm with a heart rate of approx. 70 bpm is seen. This is followed by sinus arrest of just under 3000 ms, followed by a junctional escape beat (no preceding P wave, QRS remains narrow). After a further pause of just under 2000 ms, 2 sinus node beats follow, which merge into a sinus tachycardia or atrial tachycardia (heart rate approx. 120 bpm here).
Submitted by Dr A Röschl on Tue, 07/30/2024 - 03:13
The first 3 beats are sinus node beats, all have the same morphology of the P wave. This is followed by a PAC, which is conducted via the fast pathway in the AV node. The next PAC is conducted via the slow pathway, then the AV nodal reentry tachycardia (slow/fast) starts. The retrograde P waves are visible at the end of the QRS complex in the lower lead K3.
