The Critical Role of Lambda-Shaped QRS-ST-T Wave Fusion ST-Elevation in Diagnosing and Managing Takotsubo Cardiomyopathy: A Case Report and Review of Literature

Figure 1. ECG evolution from the time of admission to the episode of acute chest pain and STEMI code activation. (A) Baseline ECG with sinus rhythm, nonspecific ST changes, and a prolonged QTc (purple line) at time of admission. (B) ECG during acute episode of chest pain revealed sinus rhythm with ST elevation (red arrows) in leads I, aVL, and V2-V6, with reciprocal ST depression and T wave inversion in the inferior leads (green arrows). The lambda-shaped triangular morphology resulting from the fusion of the QRS-ST-T waveforms raises the concern for an anterolateral OMI with likely LM or LAD culprit high-risk lesion with a large burden of myocardial ischemia. Interestingly, the inferior leads have reciprocal ST depressions that resemble reciprocal lambda-shaped QRS-ST-T wave fusion morphology. ECG: Electrocardiogram; STEMI: ST-elevation myocardial infarction; LM: left main coronary artery; LAD: left anterior descending artery; OMI: occlusive myocardial infarction.

Figure 2. SVT during acute chest pain event and after synchronized cardioversion. (A) ECG with SVT at ~ 150 bpm with a QRS width of 120 ms (red dashed lines), with retrograde P waves following each QRS complex suggesting a fast-slow re-entry tachycardia. Note the upright P waves in V1 with the appearance of pseudo R' waves (green arrow). Inverted P waves can be seen in II, III, and aVF (blue arrows). Upright retrograde P waves can also be appreciated in I and aVR (purple arrows). The retrograde P waves resolved on the resolution of arrhythmia, as seen in leads I and II, aVR, and V1 (B-D). The persistence of the baseline QRS axis and morphology was helpful to distinguish the SVT from ventricular tachycardia. Patients with a triangular QRS-ST-T waveform fusion can pose a significant challenge when evaluating for malignant arrhythmias. When there is a preexisting conduction abnormality, an SVT can appear to have a wide QRS complex, but the morphology and axis should be identical to the sinus QRS – as seen in this case when the morphology of (A) is compared with (B-D). In cases of rate-related aberrant conduction, the QRS can also appear widened. ECG: Electrocardiogram; SVT: supraventricular…

Figure 3. Emergent coronary angiography and ventriculography. Emergent coronary angiography revealed the absence of obstructive coronary artery disease (A-C). Ventriculography revealed severe LV dysfunction with LVEF of 20-25% with predominant mid-ventricular wall akinesis (red arrowheads), sparing of the apex (yellow arrowheads), and hyperkinesis of the anterobasal and inferobasal segments (orange arrowheads). An associated moderate-to-severe (Seller's grade +3) acute MR can be appreciated on ventriculography (E). Strain polar plot (F) by TTE speckle-tracking revealed decreased longitudinal strain affecting predominantly the mid-ventricular segments and sparing the apical and basal segments. However, the anterior and anteroseptal basal and mid segments have decreased longitudinal strain, consistent with myocardial injury of the LAD territory distribution. This strain analysis is consistent with a large burden of myocardial mass that correlates with the large anterolateral myocardial injury pattern suggested by the ECG. LM: Left main coronary artery; LCx: left circumflex coronary artery; OM: obtuse marginal coronary artery branches; LAD: left anterior descending coronary artery; RCA: right…

Figure 4. ECG evolution after acute event (day 0) to day 3. As the patient clinically improved, the ST elevations and QRS widening improved (A-C) without forming pathological Q-waves. ECG: Electrocardiogram