Shark Fin Sign on a 12-Lead ECG

Figure

Extract from a 12-lead ECG

A 57-year-old male patient was presented to the cardiac arrest center following out-of-hospital cardiac arrest. His primary rhythm was asystole. Cardiopulmonary resuscitation was required for a cumulative period of 75 min before sustained spontaneous circulation returned. The ECG showed a characteristic finding, indicating the need for prompt left heart catheterization. Emergency echocardiography revealed biventricular systolic dysfunction and a ventricular septal defect (VSD). The ECG shows what is referred to as the shark fin sign. In the inferior leads, the large R wave (1mV) merges with the ST segment. Reciprocal extreme ST depressions can be seen. Myocardial infarction with inferior and posterior involvement complicated by VSD and cardiogenic shock was diagnosed. Systematic reports are limited, but observational data suggest significantly higher mortality in myocardial infarction patients with the shark fin sign. The cause appears to be that the phenomenon occurs in the case of extensive myocardial damage. The patient died of refractory cardiogenic shock on the same day as admission. In addition to the ECG findings, clinical predictors of a fatal outcome included right heart involvement and post-infarction VSD.

Dr. med. Sascha Macherey-Meyer, Dr. med. Johannes Terporten, PD Dr. med. Christoph Adler
Universität zu Köln, Medizinische Fakultät und Uniklinik Köln, Klinik III für Innere Medizin, [e-mail]

Conflict of interest statement: The authors state that no conflict of interest exists.

Translated from the original German by Christine Rye.

Cite this as: Macherey-Meyer S, Terporten J, Adler C: Shark fin sign on a 12-lead ECG. Dtsch Arztebl Int 2024; 121: 680.
DOI: 10.3238/arztebl.m2024.0089