Anatomical classification of left atrial appendages in specimens applicable to CT imaging techniques for implantation of amplatzer cardiac plug.
BACKGROUND
Certain anatomical characteristics of the left atrial appendage (LAA) are associated with complexity in the implantation of occluder devices.


OBJECTIVE
The aim was to define characteristics measurable by three-dimensional imaging that would predict complexities both in the implantation procedure and the selection of the appropriate device size.


METHODS
An anatomical study was performed of 50 postmortem hearts, of which 15 had a history of atrial fibrillation, and of 30 consecutive patients undergoing LAA occlusion with the Amplatzer cardiac plug (ACP). The specimens were classified according to variables that can be visualized using computerized tomography (CT). The CT scans of 30 consecutive patients were classified according to the level of the LAA ostium, the left lateral ridge (LLR), the LAA limbus and distance from LAA to the mitral annulus before undergoing LAA occlusion, and the results were correlated.


RESULTS
Three types of LAA orifice were defined: type I, with a usually higher, anterior LAA ostium, a short, flattened and wide LLR and almost nonexistent limbus; type II, presenting a long, pointed and narrow LLR, and a longer, more defined limbus; type III, with a lower LAA ostium, close to the left atrium floor and the mitral annulus, a marked separation from the left pulmonary vein orifices and a limbus of intermediate length.


CONCLUSIONS
LAA with lower ostia are more difficult to occlude. Types II and III have very prominent LLRs with longer limbi, which may increase the difficulty of inserting the guide and making measurements for selection of the right ACP size.
Interventional Cardiology Section, Cardiology Department, Infanta Cristina University Hospital, Badajoz, Spain.
José R
JR
López-Mínguez
Interventional Cardiology Section, Cardiology Department, Infanta Cristina University Hospital, Badajoz, Spain.
Reyes
R
González-Fernández
Interventional Cardiology Section, Cardiology Department, Infanta Cristina University Hospital, Badajoz, Spain.
Concepción
C
Fernández-Vegas
Interventional Cardiology Section, Cardiology Department, Infanta Cristina University Hospital, Badajoz, Spain.
Victoria
V
Millán-Nuñez
Interventional Cardiology Section, Cardiology Department, Infanta Cristina University Hospital, Badajoz, Spain.
María E
ME
Fuentes-Cañamero
Interventional Cardiology Section, Cardiology Department, Infanta Cristina University Hospital, Badajoz, Spain.
Juan M
JM
Nogales-Asensio
Interventional Cardiology Section, Cardiology Department, Infanta Cristina University Hospital, Badajoz, Spain.
Javier
J
Doncel-Vecino
Interventional Cardiology Section, Cardiology Department, Infanta Cristina University Hospital, Badajoz, Spain.
Javier
J
Elduayen-Gragera
Cardiac Morphology Unit, Royal Brompton Hospital, London, UK.
Siew Y
SY
Ho
Department of Anatomy and Cell Biology, Faculty of Medicine, Extremadura University, Spain.
Damián
D
Sánchez-Quintana
D000368:Aged; D020517:Atrial Appendage / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D002102:Cadaver; D006801:Humans; D021621:Imaging, Three-Dimensional; D008137:Longitudinal Studies; D008297:Male; D011446:Prospective Studies; D019919:Prosthesis Implantation / Q000379:methods*; D055989:Septal Occluder Device; D014057:Tomography, X-Ray Computed
Amplatzer occluder device; atrial appendage; computer generated imaging; tomography