A 52-year-old man with a history of hypertension presents to the emergency department with a 2-hour history of substernal chest pain that resolved 30 minutes before arrival. He is currently pain-free and hemodynamically stable. His 12-lead ECG is shown. The structure marked **B** in the diagram demonstrates symmetric deep T-wave inversion in V3. Which of the following best describes the clinical significance of this finding in the context of his presentation?

Explanation

## Why Wellens syndrome (option 1) is correct The symmetric deep T-wave inversion in V3 (marked **B**), combined with the clinical context of recent resolved chest pain and currently pain-free status, is pathognomonic for Wellens syndrome. This ECG pattern, first described by de Zwaan and Wellens in 1982, signifies critical proximal LAD stenosis (>70–90%) and identifies patients at extremely high risk of impending massive anterior wall MI. The T-wave changes reflect reperfusion after spontaneous resolution of transient occlusion. Wellens syndrome is a cardiac emergency even when the patient is pain-free, and 75% of unrevascularized patients develop a large anterior MI within a mean of 8.5 days. The diagnosis mandates urgent coronary angiography with intent to revascularize via PCI of the LAD lesion (Harrison 21e Ch 269; Goldberger 9e). ## Why each distractor is wrong - **Completed anterior wall MI (option 2)**: Completed anterior MI would show loss of R-wave progression (pathologic Q waves in V1–V4) and absence of viable myocardium. The diagram explicitly shows preserved R-wave progression (marked **D**), which excludes completed MI and is a key criterion for Wellens syndrome. - **Takotsubo cardiomyopathy (option 3)**: While Takotsubo can present with deep T-wave inversions in precordial leads, it typically follows emotional or physical stress, is associated with apical ballooning on echocardiography and reduced ejection fraction, and does not carry the same imminent risk of massive anterior MI as Wellens syndrome. The clinical context of anginal chest pain (not emotional trigger) and the specific ECG pattern favor Wellens. - **Pulmonary embolism (option 4)**: PE with RV strain produces T-wave inversion in V1–V4, but is accompanied by right axis deviation, S1Q3T3 pattern, sinus tachycardia, and clinical context of acute dyspnea or hemodynamic instability. This patient's presentation and ECG pattern are inconsistent with PE. **High-Yield:** Wellens syndrome = pain-free patient + symmetric deep T-wave inversion in V2–V3 + recent anginal history + preserved R-wave progression + isoelectric/minimally elevated ST segment = critical proximal LAD stenosis = cardiac emergency requiring urgent angiography (NOT stress testing). [cite: Harrison 21e Ch 269; Goldberger's Clinical Electrocardiography 9e; de Zwaan et al. 1982]