Variability of the Left Atrial Appendage in Human Hearts

Abstract

Atrial fibrillation increases the risk of thrombus formation. It is commonly responsible for cerebral stroke whereas less frequently for pulmonary embolism. The aim of the study was to describe the morphology of the left atrial appendage in the human heart with respect to sex, age and weight. Macroscopic examination was carried out on 100 left appendages taken from the hearts of the patients aged 18–77, both sexes. All hearts preserved in 4% water solution of formaldehyde carried neither marks of coronary artery disease nor congenital abnormalities. Three axes of appendage orientation were performed. After the appendage had been cut off, morphological examination was performed in long and perpendicular axes. Measurements of the appendages were taken from anatomical specimens and their silicone casts. We classified the left atrial appendage into 4 morphological groups according to the number of lobes. Most left atrial appendages in female population were composed of 2 lobes. In the male group typically 2 or 3-lobed appendages were observed. The mean left atrial appendage orifice ranged from 12.0 to 16.0 mm and the most significant difference in the orifices between males and females was observed in LAA type 2 (about 3.3 mm). A smaller orifice and narrower, tubular shape of the LAA lobes could explain a higher risk of thrombus formation during nonvalvular atrial fibrillation in women. Knowledge of anatomical variability of the LAA helps diagnose some undefined echoes in the appendage during transesophageal echocardiographic examination.

Evaluation of the left atrial appendage by real time three‐dimensional transesophageal echocardiography online

“…Veinot et al observed a series of autopsies comprising 500 normal human hearts (age range: 0–100 years) and found that the distribution of number of LAA lobes was 2 (54%), 3 (23%), 1 (20%), and 4 (3%). Kamiński et al confirmed considerable morphological differences in LAA. On the basis of 220 LAA casts examinations, Ernst et al observed variability of LAA.…”

A novel approach to visualization of the right ventricular outflow tract

“…The first stage of the research was to construct right ventricle models using a silicone molding compound (Xiameter 4250 S Green). The applied technique has already been used in the case of modeling the heart's appendages [10]. Before modeling, the hearts were thoroughly rinsed with cold water to remove blood clots from the inside.…”

Newly Diagnosed Stroke-Associated Atrial Fibrillation: Risk of Development of Unfavorable Clinical Outcomes (The Results of the Subanalysis Cohort Study Apollo)

“…С точки зрения патогенеза формирования процесса тромбообразования достаточно сложно представить, что эпизод вдФП вызвал тромбоэмболию, привед-шую к нарушению мозгового кровотока с развитием обширного повреждения головного мозга со столь выраженным неврологическим дефицитом. Воз-можно, последующие исследования должны быть связаны, в том числе, с изучением особенностей гео-метрии ушка левого предсердия, его анатомо-мор-фологических особенностей, приводящих в столь коротком временном периоде к тромбообразованию [18]. Безусловно данные вопросы требуют прове-дения специально спланированных исследований у пациентов с вдФП.…”