Syncope and 2:1 Atrioventricular Block in a Middle-Aged Man
Arihant Jain1, Nathan Balamurugan2
1Department of Emergency Medicine, All India Institute of Medical Sciences, New Delhi, India.
JACC. Case Reports
|July 30, 2026
Summary
Syncope with new atrioventricular block can indicate acute coronary occlusion. Early detection of inferior myocardial infarction through ECG changes is crucial for timely reperfusion therapy.
Area of Science:
- Cardiology
- Emergency Medicine
Background:
- Syncope and bradycardia can present without typical chest pain.
- Atrioventricular block requires thorough electrocardiogram (ECG) evaluation.
Purpose of the Study:
- To highlight the association between syncope, atrioventricular block, and acute coronary occlusion.
- To emphasize the importance of recognizing subtle ECG changes indicative of myocardial infarction.
Main Methods:
- Case report of a middle-aged man presenting with syncope and 2:1 atrioventricular block.
- ECG analysis revealing hyperacute T waves and ST-segment changes in inferior leads.
- Urgent coronary angiography and successful percutaneous coronary intervention.
Main Results:
- Proximal right coronary artery occlusion was identified as the cause.
- Successful revascularization led to resolution of symptoms.
- The case demonstrates a link between syncope, AV block, and acute myocardial infarction.
Conclusions:
- Syncope with new atrioventricular block necessitates careful ECG assessment, especially inferior leads, for ischemic changes.
- Subtle ECG findings in high-grade atrioventricular block may indicate inferior myocardial infarction.
- Prompt reperfusion therapy is vital for symptomatic bradycardia caused by acute coronary occlusion.
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