Shark Fin Electrocardiogram: A Deadly Electrocardiogram Pattern in ST-Elevation Myocardial Infarction (STEMI)

Abstract

Shark fin electrocardiographic (ECG) pattern, also known as 'Lambda-wave', 'giant R waves', or 'triangular QRS-ST-T waveform' is a dangerous ECG pattern associated with ST-elevation myocardial infarction (STEMI). It is formed by the fusion of QRS, ST, and T waves and predicts the high risk of mortality due to cardiogenic shock and ventricular fibrillation. The management should be aggressive with reperfusion via thrombolysis or percutaneous intervention, ideally in the intensive care unit with ventricular assist devices. This ECG pattern may be misdiagnosed as wide complex tachycardia or the ECG changes of hyperkalemia. Thus, differentiating it from other conditions causing similar ECG changes and prompt management is highly important to save the patient from serious complications. Here we have presented a case of STEMI with shark fin ECG associated with pulmonary edema (Killip class III acute myocardial infarction).

Shark Sighting in an Electrocardiogram

“…Although the ST elevations were downsloping instead of the more typical concave upward or “tombstoning,” this pattern has been associated most often with injury due to left anterior descending coronary occlusion . Although rare (it is seen in just 1.4% of ST-elevation myocardial infarctions [STEMIs]), it is critically important to recognize this pattern that has been called the triangle, lambda (λ), or shark fin pattern. Less often, it has been associated with stress (also known as Takotsubo) cardiomyopathy, and rarely, with acute myocarditis …”

Shark Fin Electrocardiogram: A Deadly Electrocardiogram Pattern in Takotsubo Cardiomyopathy During 15 Years of Follow-Up

“…SFE is known to be a poor prognostic factor associated with cariogenic shock and ventricular fibrillation, thus it's known as the deadly ECG sign. SFE is commonly found to be an indicator of severe ACS and ischemic heart disease [15]. TTC is a non-ischemic cause of the SFE associated with the downsloping of the ST segment pattern.…”

Acute Stanford type A aortic dissection with the “giant R wave” electrocardiogram pattern: a case report

“…Capturing this ECG pattern can often be challenging due to delayed seeking of medical attention [5] . This distinctive ECG pattern if frequently associated with a high risk of cardiac arrest, cardiogenic shock and ventricular brillation, leading to potentially fatal outcomes [3][4][5] .TAAD is a life-threatening disorder with a high mortality rate [1,2] , especially when complicated by coronary artery involvement. Aortic dissection extended into coronary arteries leads to acute myocardial infarction (MI), resulting in poor prognosis [7][8][9][10] .…”

“…Stanford type A aortic dissection (TAAD) is a life-threatening cardiovascular event with a signi cantly high mortality rate if not promptly treated [1,2] . The "giant R wave" electrocardiogram (ECG) pattern is a dangerous ECG pattern associated with ST-elevation myocardial infarction (MI), most commonly involving occlusion of the left main coronary artery, which carries a high risk of cardiac arrest, cardiogenic shock, and ventricular brillation, leading to potentially fatal outcomes [3][4][5] . The concurrence of acute TAAD and MI with the "giant R wave" ECG pattern is an extremely rare condition.…”