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Patient With Presyncope and Variable PR Interval and QRS Morphology.

Alex Bittner¹, Alejandro Paredes¹, Ismael Vergara¹

¹Department of Cardiology, Pontificia Universidad Católica de Chile, Santiago de Chile, Chile.

JACC. Case Reports

|September 10, 2021

Summary

A 72-year-old female experienced presyncope due to a variable PR interval and changing QRS morphology on her electrocardiogram. This case highlights important diagnostic considerations for irregular heart rhythms.

Keywords:

AV, atrioventricular ECG, electrocardiogram LAFB, left anterior fascicular block LBBB, left bundle branch block RBBB, right bundle branch block bundle branch block conduction disturbance infra-his block

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Area of Science:

Cardiology
Clinical Electrocardiography

Background:

Presyncope is a concerning symptom requiring thorough cardiac evaluation.
Electrocardiogram (ECG) abnormalities, such as variable PR intervals and changing QRS morphology, can indicate underlying arrhythmias.

Purpose of the Study:

To present a case of presyncope associated with specific ECG findings.
To discuss the differential diagnosis for such presentations.

Main Methods:

Case report of a 72-year-old female patient.
Electrocardiogram analysis revealing variable PR interval and changing QRS morphology.
Review of potential etiologies and diagnostic pathways.

Main Results:

The patient presented with presyncope.
Electrocardiogram demonstrated a variable PR interval and dynamic QRS changes.
Differential diagnoses were considered based on the clinical presentation and ECG findings.

Conclusions:

Variable PR interval and changing QRS morphology on ECG can be associated with presyncope.
A systematic approach to differential diagnosis is crucial for managing patients with these findings.