The electrocardiographic 'triangular QRS-ST-T waveform' pattern: a marker of severe haemodynamic compromise in Takotsubo syndrome-a case report

Shark fin ECG pattern in a patient with acute ascending aortic dissection

The 'shark-fin' ECG-sign is a rare electrocardiographic pattern seen in ACS, typically associated with poor prognosis. However, its manifestation in acute aortic syndromes remains largely unexplored. Here, we present a case of a patient diagnosed with Ascending Aortic Dissection, who presented to ED with acute chest pain and shark-fin ECG-pattern.

Shark fin sign: A rare EKG finding in a patient with Takotsubo cardiomyopathy from influenza A infection

This case demonstrated the rare "shark fin" ECG pattern, an ST-segment elevation typically seen in acute myocardial infarction. We reported a case of takotsubo cardiomyopathy secondary to influenza A infection with multiple organ failure, showing the shark fin sign and resulting in in-patient mortality and various complication.

Wide QRS Complex Transient Pattern in a Patient With Severe COVID-19

This case report describes a patient in their 60s with shortness of breath who tested positive for COVID-19.

SHARK FIN ECG PATTERN IN A PATIENT WITH TAKOTSUBO SYNDROME - CASE STUDY AND LITERATURE REVIEW

Shark fin or triangular QRS-ST-T waveform ECG pattern, also known as lambda-wave ST elevation or giant R wave syndrome, is a particular ECG presentation where QRS complex, ST-segment and T-wave are fused in a unique complex. Originally described in some patients with ST-segment elevation myocardial infarction (STEMI) during the acute phase, it has been found to be associated with a high risk of ventricular fibrillation and cardiogenic shock as well as with a high in-hospital mortality. However, shark fin ECG pattern has also been reported in patients with non-acute coronary syndrome related ST-elevation (NASTEP), including stress-induced takotsubo syndrome (TTS). Fourteen such cases (all females) have been reported so far. The authors present a case of a 56-year-old male with shark fin ECG pattern associated with TTS triggered by burn injuries of head, back, upper, lower limbs and the respiratory tract. Due to respiratory insufficiency and heart failure with hemodynamic compromise, he required mechanical ventilation and catecholamines use. Echocardiography showed apical and midventricular akinesia with left ventricular ejection fraction and global longitudinal strain reduced to 30% and -6.8%, respectively and a high segmental post-systolic index. Shark fin pattern maintained within 2 days, then ST-T evolution was observed. Echocardiographic improvement followed by almost normalization were seen after 6 and 9 days, respectively. No cardiac arrhythmias were recorded as in most of the described cases with shark fin ECG and TTS.

A single-center retrospective study on the incidence and clinical significance of the electrocardiographic "Triangular QRS-ST-T Waveform" pattern*

BACKGROUND

The triangular QRS-ST-T waveform is a rare presentation of ST-segment elevation acute myocardial infarction associated with a poor in-hospital prognosis.

OBJECTIVE

To evaluate the incidence and clinical implications of the QRS-ST-T waveform pattern.

METHODS

Clinical data from non-pregnant adult patients who presented as STEMI activations at a single institution between 2017 and 2021 were reviewed. Patients who met electrocardiographic criteria for triangular QRS-ST-T waveform - a giant wave from the fusion of the QRS complex, the ST-segment, and the T-wave - were included in the study.

RESULTS

There were 417 STEMI activations, eight (1.9%) of which fulfilled the criteria for the triangular QRS-ST-T waveform pattern on electrocardiography. Coronary angiography was performed in five of these patients, four of whom demonstrated a significant lesion to the left anterior descending artery. Three patients did not undergo angiography secondary to hemodynamic instability. Seven of the patients in our study experienced cardiogenic shock requiring vasopressor, inotropic, and/or mechanical support. Only two patients survived to discharge; one was successfully bridged to coronary artery bypass grafting via intra-aortic balloon pump, while the other underwent a staged percutaneous coronary intervention.

CONCLUSIONS

The triangular QRS-ST-T waveform pattern is a rare ECG finding that may indicate hyper-acute STEMI and is an ominous sign of impending hemodynamic instability. Patients who survived received prompt aggressive therapeutic management.

Update of Takotsubo cardiomyopathy: Present experience and outlook for the future

Takotsubo cardiomyopathy (TTS) has become a recognised clinical entity since the Japanese scientist Sato first described it in 1990. Despite an increasing number of confirmed cases, especially during the COVID-19 pandemic, its pathophysiology remains incompletely understood, and decision-making differs in the diagnosis and treatment. In addition, it is not evident whether a significant increase in TTS is due to better understanding among practitioners and widespread access to coronary angiography, or if it is a reflection of an actual increase in incidence. We analysed a series of international research studies from 1990 to 2021. Beyond epidemiology and clinical presentation, we evaluated and summarised fundamental knowledge about various predisposing factors, with particular attention to the iatrogenic impact of certain drugs, namely antidepressants, chemotherapy, and antiarrhythmics. Furthermore, we highlighted the main pathophysiological theories to date. In addition, based on published studies and clinical cases, we investigated the role of numerous diagnostic approaches in the differential diagnosis of TTS and identified predictors of TTS complications, such as cardiogenic shock, ventricular fibrillation, and left ventricular thrombi. Accordingly, we sought to propose a diagnostic algorithm and further treatment management of TTS under the presence of possible complications to help practitioners make more informed decisions, as the initial presentation continues to pose a challenge due to its close similarity to acute coronary syndrome with ST-elevation. In conclusion, this article examines Takotsubo cardiomyopathy from different perspectives and, along with future systematic reviews and meta-analyses, can be of particular interest to practising cardiologists and researchers in developing clinical guidelines.

Electrocardiographic presentation of acute left main coronary artery occlusion misinterpreted as ventricular tachycardia

We present a case of acute left main coronary artery (LMCA) occlusion that manifested cardiogenic shock and an ST-segment elevation myocardial infarction (STEMI) electrocardiographic (ECG) pattern comprising "triangular" or "lambda-like" QRS-ST-T complexes. The presenting ECG pattern was misinterpreted as ventricular tachycardia (VT) with resultant delayed emergency percutaneous coronary intervention. The patient died of intractable cardiogenic shock. This case corroborates previous research findings associating the ECG pattern comprising "triangular" or "lambda-like" QRS-ST-T complexes observed in the clinical setting of acute myocardial ischemia with acute LMCA occlusion. Also, we demonstrate how this ECG pattern should be scrutinized for ST-segment elevation in order to avoid misdiagnosing a STEMI for VT.

A 'shark'-masked electrocardiogram: case report of a Tako-Tsubo syndrome

Background

Triangular ST-segment elevation or 'shark-fin' sign has been described as a specific indicator of acute coronary occlusion and large myocardial ischaemia, translating into poorer prognosis. However, this electrocardiographic presentation has been reported in rare cases of Tako-Tsubo syndrome and associated with more severe physical stressors and neurological involvement.

Case summary

We present a rare case of a 51-year-old woman presenting with incoming epileptic attacks and concomitant pyometra. Despite controlling epilepsy with phenytoin and the surgical treatment of the infection, she developed sepsis requiring vasopressors, and thereafter sustained ventricular tachycardia and diffuse ST-segment elevation with the 'shark-fin' sign. TTC was confirmed by the documentation of normal coronary arteries and the complete recovery of wall motion abnormalities at discharge.

Discussion

Heterogeneous presentation and triggering conditions often challenge the diagnosis of Tako-Tsubo syndrome. The acknowledgement of different electrocardiographic and clinical manifestations can ease the diagnosis and the successful management of these patients, whose prognosis can be extremely severe in the acute phase, if unidentified.