[CASE] 'Shark Fin' sign - true killer among ECG ischemic patterns

56-year-old man in shock was brought to ED by EMS in the early hours of the morning. There was no history of previous CVD or angina. Patient was an active cyclist and recently has been preparing for a triathlon. This ECG was obtained.

The first thing that comes to mind is we have accelerated sinus rhythm with RBBB + LAHB or some ICVD pattern here. This very wide, abnormal looking QRS may suggest hyperkalemia. But when you look closer to V4-V6 you can see that QRS is narrow there which proves the "giant R'-wave" present in anterolateral leads is in fact a massive ST elevation (with reciprocal ST depression in inferior leads).

Bedside ultrasound showed anterior and lateral wall motion abnormalities which confirmed it is an extensive ANTEROLATERAL STEMI and cath lab was activated immediately.

First injection of contrast dye revealed a huge thrombus blocking left main artery. At first flow was restored partially and intracoronary abciximab was administered. Then patient arrested and CPR via LUCAS was conducted. An aspiration trombectomy was performed but with no major effect on a very poor flow. CPR was unsuccesful...

This case shows Shark Fin sign (also known as "giant R-wave" which is somewhat misleading name) is associated with very high mortality and poor prognosis. It's worth to know this pattern so the patient can be referred to cath lab as soon as possible.



Great posts from Dr. Smith's ECG blog about Shark Fin:

1. http://hqmeded-ecg.blogspot.com/2018/06/shark-fin-deadly-ecg-sign-that-you-must.html
2. http://hqmeded-ecg.blogspot.com/2015/07/giant-r-waves-what-are-they.html
3. http://hqmeded-ecg.blogspot.com/2016/03/shark-fin-ecg-in-i-avl-v4-and-v5-which.html