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Accessory atrioventricular pathways that conduct only in the antegrade direction
Circulation
|December 1, 1980
Summary
Patients with Wolff-Parkinson-White syndrome and accessory atrioventricular pathways conducting only antegrade are older and typically present with atrial fibrillation later in life. Their pathway properties are similar to bidirectional pathways.
Area of Science:
- Cardiology
- Electrophysiology
- Cardiac Electrophysiology
Background:
- Accessory atrioventricular pathways are a hallmark of Wolff-Parkinson-White syndrome.
- These pathways can exhibit antegrade, retrograde, or bidirectional conduction.
- Exclusive antegrade conduction represents an uncommon variant.
Purpose of the Study:
- To describe patients with accessory pathways exhibiting only antegrade conduction.
- To compare these patients with those having bidirectional accessory pathways.
- To analyze clinical presentation and electrophysiological characteristics.
Main Methods:
- Retrospective analysis of 143 patients with single accessory pathways.
- Categorization into exclusive antegrade (n=7), bidirectional (n=111), and exclusive retrograde (n=25) conduction groups.
- Comparison of demographic, clinical, and electrophysiological data.
Main Results:
- Patients with exclusive antegrade conduction were significantly older (42 years) than the bidirectional group (31.4 years).
- Antegrade refractoriness and conduction properties were similar between exclusive antegrade and bidirectional groups.
- Exclusive antegrade group predominantly presented with atrial fibrillation (6/7), while the bidirectional group showed various arrhythmias.
Conclusions:
- Accessory pathways with exclusive antegrade conduction are rare in Wolff-Parkinson-White syndrome.
- These patients often remain asymptomatic until developing atrial fibrillation with age.
- Functional properties of antegrade conduction are comparable to bidirectional pathways despite lack of retrograde conduction.
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