Abstract
Background: Atrial fibrillation (AF) is the most common sustained clinical arrhythmia. Myocardial sleeves onto pulmonary veins (PVs) have been recognized as a frequent site of origin of focal triggers for this arrhythmia.
Expression of Leu-7 has been hypothesized to correspond with abnormal atrial automaticity. Objective: To evaluate a possible role of the Leu-7 immunoreactivity in AF patients, we studied Leu-7 expression in myocardial sleeves.
Methods: Leu-7 was studied immunohistochemically in paraffin-embedded specimens from 55 human autopsied hearts (mean age 69 years, range 42-94 years, 34 males, 21 females). Twenty-two of the subjects had previous history of AF.
Conclusions: Leu-7 positivity, hypothesized to correspond with abnormal atrial automaticity, can be detected in some myocardial sleeves around PVs. However, no statistical relationship to previous history of AF was found.