Wellens' Syndrome

Overview

Wellens' syndrome is a critical electrocardiographic (ECG) pattern that indicates a high risk of imminent anterior wall myocardial infarction, typically due to significant stenosis of the proximal left anterior descending (LAD) coronary artery. Sometimes referred to as “LAD coronary T-wave syndrome,” it is a pre-infarction state that often appears in pain-free patients who had recent episodes of angina. Recognition of Wellens’ syndrome is vital in emergency and cardiac care settings, as failure to promptly identify and treat the condition may result in a large anterior myocardial infarction within days.

Causes

The underlying cause of Wellens’ syndrome is a critical narrowing or partial occlusion of the proximal segment of the LAD coronary artery, which supplies a significant portion of the left ventricle. The characteristic ECG findings occur when blood flow is temporarily restored (reperfusion) after transient ischemia due to the narrowing. While patients may be asymptomatic during evaluation, the condition reflects unstable coronary artery disease and an impending risk of a large heart attack. Contributing risk factors include:

• Coronary artery disease (CAD)

• Hypertension

• Smoking

• Diabetes mellitus

• Hyperlipidemia

• Family history of heart disease

Symptoms

Patients with Wellens’ syndrome may present with a history of angina, particularly chest pain episodes that have recently resolved. However, they are often asymptomatic at the time of presentation. Key clinical features include:

• Recent chest pain or angina: Typically resolves before the ECG changes are recorded.

• Pain-free intervals: Patients may appear well and symptom-free at the time of evaluation, making ECG interpretation crucial.

• Minimal or no elevation in cardiac enzymes: In contrast to full-thickness myocardial infarction, initial cardiac biomarkers may be normal or only mildly elevated.

• No signs of heart failure or shock initially: Because the infarction has not yet occurred.

The risk lies in the potential for rapid progression to a massive anterior wall myocardial infarction if not treated promptly.

Diagnosis

Diagnosis of Wellens’ syndrome is made primarily through ECG interpretation, supported by clinical history and risk factor assessment. Essential diagnostic criteria include:

Electrocardiogram (ECG) Findings

• Type A Wellens’ pattern: Biphasic T-waves in leads V2–V3 (initial positivity followed by terminal negativity).

• Type B Wellens’ pattern: Deep, symmetric, inverted T-waves in leads V2–V4 (more common form).

• Preserved R wave progression: No significant Q waves or loss of R waves in the precordial leads.

• Minimal or no ST-segment elevation: Unlike acute MI, there is typically no ST elevation at the time of recording.

• ECG recorded during pain-free period: T-wave abnormalities occur after resolution of symptoms.

Additional Diagnostic Workup

• Cardiac biomarkers: Troponin and CK-MB levels may be normal or mildly elevated.

• Echocardiography: May show wall motion abnormalities depending on ischemia severity.

• Coronary angiography: Confirms critical stenosis of the proximal LAD artery and is crucial for definitive diagnosis and management planning.

Treatment

Wellens’ syndrome represents a high-risk cardiac condition requiring urgent intervention. The cornerstone of treatment is early recognition followed by definitive revascularization. Management includes:

Immediate Actions

• Hospital admission: For cardiac monitoring and further evaluation.

• Avoidance of stress testing: Exercise or pharmacological stress testing is contraindicated due to risk of provoking full-blown infarction.

Definitive Treatment

• Urgent coronary angiography: To visualize the extent of LAD stenosis.

• Percutaneous coronary intervention (PCI): Balloon angioplasty with stent placement is the preferred treatment.

• Coronary artery bypass grafting (CABG): May be required in some cases depending on the extent and location of coronary disease.

Medical Therapy

• Antiplatelet agents: Aspirin and/or P2Y12 inhibitors (e.g., clopidogrel) to prevent clot formation.

• Beta-blockers: To reduce myocardial oxygen demand.

• Statins: For lipid control and plaque stabilization.

• Nitrates and ACE inhibitors: Used as needed for symptom control and cardiovascular protection.

Prognosis

The prognosis of Wellens’ syndrome is highly dependent on timely diagnosis and intervention. Without treatment, the condition almost invariably leads to extensive anterior wall myocardial infarction within days to weeks, carrying a high risk of morbidity and mortality. However, with early coronary angiography and revascularization, the prognosis becomes excellent, and myocardial infarction can be prevented. Long-term outcomes are generally favorable if risk factors are controlled and medical therapy is maintained. Continued follow-up with a cardiologist is essential to monitor cardiac function and ensure adherence to preventive strategies.