Myocardial extensions around pulmonary veins (PVs) have been recognized as the most important sites of origin for arrhythmogenic foci that trigger @entity955 . The aim of this study was to evaluate the characteristics of @entity955 in pulmonary veins from subjects with and without a history of @entity955 . A total number of 43 @entity1 hearts obtained at autopsy were studied (27 @entity1 , 16 @entity1 , mean age 67 +/- 8 years). Sixteen subjects (group 1) had a history of @entity955 (11 @entity1 , mean age 66 +/- 10 years). The remaining 27 subjects (group 2) were without @entity943 (16 @entity1 , mean age 68 +/- 8 years). The presence and morphology of the myocardial extensions were studied microscopically. Of the total number of 172 PVs evaluated, myocardial extensions were revealed in 117 (68%) cases. Myocardial fibers were arranged in a variable manner with the most prevailing circular pattern. Continuous extensions were present in 74, while a discontinuous pattern was revealed in 29 PVs. Maximum extension of the sleeves reached 48 mm (mean 7.7-10 mm) and their maximum thickness was 5 mm. Myocardial extensions were longer and thicker in the upper PVs from subjects with previous @entity955 . In conclusion, a significant interindividual variability in the presence, arrangement, and thickness of @entity296 into PVs was revealed. @entity1 with a history of @entity955 were found to have longer and thicker myocardial extensions into the upper PVs, and this finding may have implications for the catheter ablation technique.

Anatomic characteristics of extensions of @entity955 into the pulmonary veins in subjects with and without XXXX .

@entity1 :: ('9606', 'Species') :: ['women', 'Patients', 'human', 'men'] @entity296 :: ('MESH:D009202', 'Disease') :: ['atrial myocardial sleeves'] @entity943 :: ('MESH:D001145', 'Disease') :: ['arrhythmia'] @entity955 :: ('MESH:D001281', 'Disease') :: ['atrial fibrillation', 'atrial myocardium']
@entity955 :: (MESH:D001281,Disease) :: ['atrial fibrillation']
