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 XXXX into the pulmonary veins in subjects with and without @entity955 .

@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 myocardium']
