Found this "gem" buried deep-down in the back of the vault and have wanted to share it for many months. Due to the impressive QRS voltage and overlapping waveforms, I initially debated on whether or not I should post this at 1/2-standard but in the end I decided to retain its original size. This ECG is from 27 years ago so I have very limited information, but this is what I do know.
Patient’s clinical data:
This ECG is a followup to "Wide Complex Tachycardia In a Patient with WPW". The patient was known to have Wolff-Parkinson-White syndrome, and presented to an urgent care center with a hemodynamically unstable wide complex tachycardia. He was successfully cardioverted by paramedics. This followup tracing clearly shows the Delta waves, indicating early activation of the ventricles through an accessory pathway. See Leads I, V3, and V4 for the clearest views of the Delta waves. The ST changes: ST elevation in Leads V1 and V2, and the T wave inversions and ST depressions in Leads II, III, aVF and V3 through V6, could represent an acute injury in the inferior-lateral wall, or post-cardioversion ST changes.
Thanks to ECG Guru Member, Sebastian Garay, for his contribution of this very interesting set of ECGs.
This ECG was submitted by Sebastian Garay, EMT-P and ECG Guru (and ECG Guru Member sebmedic). It is a very interesting case of wide complex tachycardia in a patient with Wolff-Parkinson-White.
This is from a 57 year old man who sought medical help for a complaint of palpitations. He was known to have WPW. The paramedics determined that he was hemodynamically unstable, and in light of the wide-complex tachycardia, they performed a synchronized cardioversion at 100 j. The patient converted to the rhythm shown in the next ECG. The paramedics then administered a Lidocaine bolus and drip, considering this to be a ventricular tachycardia. The patient arrived in the Emergency Dept in improved hemodynamic condition.
This ECG can be used to teach V Tach for beginner students, WPW and WCT tachycardia differential diagnosis for more advanced students. It is also a good ECG for axis discussion, and for how lead placement affects the final product.
The differential diagnosis here is 1) V Tach and 2) SVT with aberrant conduction or left ventricular conduction delay. For a discussion of ECG criteria which help us diagnose WCT, see the "Ask The Expert" column from Jan. 11, 2012. Characteristics that make this look like V Tach include: wide complex and significant left axis deviation. Features which may favor a diagnosis of SVT are the pre-existing WPW and a rate of 222/min. There are no p waves seen. NOTE: V2 in this ECG appears to reflect electrode mis-placement, as it does not "make sense" in the normal progression of the QRS complexes in the precordial leads. It is clearly "out of place".
The second ECG shows the same patient after conversion of the tachycardia. The delta waves of WPW are easily seen.
WPW is one of the "pre-excitation" syndromes caused by an accessory pathway that bypasses the AV node. This pathway is called the Bundle of Kent. This ECG clearly demonstrates the "delta wave" caused by the atrial impulse traveling around the AV node and pre-exciting part of the ventricle. Delta waves are best seen in Leads I and V4 - V6. The delta wave in Lead II is a small notch. A short PR interval is also seen. The accessory pathway can combine with the normal pathway through the AV node to form a circle or circuit, making the heart vulnerable to re-entrant tachycardia. This ECG is from a four-year-old girl, who had not been previously diagnosed.
