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Catheter Ablation in Combination With Left Atrial Appendage Closure for Atrial Fibrillation
Published on: February 26, 2013
Quantitative Evaluation of the Substantially Variable Morphology and Function of the Left Atrial Appendage and Its
Cai-Ying Li1, Bu-Lang Gao2, Xiao-Wei Liu1
1Department of Medical Imaging, Second Hospital, Hebei Medical University, Shijiazhuang, Hebei Province, PR China.
Insights
The left atrial appendage (LAA) exhibits diverse morphologies and anatomical relationships, crucial for guiding cardiac procedures. Understanding LAA structure aids in trans-catheter occlusion and ablation interventions.
Area of Science:
- Cardiovascular Imaging
- Cardiac Anatomy
- Interventional Cardiology
Background:
- The left atrial appendage (LAA) plays a significant role in cardiac function and is a common source of thrombi.
- Variations in LAA morphology and its relationship with adjacent cardiac structures are not fully understood.
Purpose of the Study:
- To quantitatively assess the morphology, anatomy, and function of the LAA.
- To investigate the relationship between LAA morphology and adjacent cardiac structures.
Main Methods:
- Cardiac multidetector computed tomography angiography was performed on 860 patients.
- Analysis included LAA morphology, orifice characteristics, and spatial relationships with surrounding anatomy.
Main Results:
- Seven LAA morphology types and 6 subtypes were identified, with Type 2 being most prevalent.
- Significant differences in LAA orifice size and LAA-mitral ring distance were observed between sexes.
- LAA morphology parameters correlated with left atrium volume and aortic dimensions, while functional volumes correlated with body metrics.
Conclusions:
- The LAA displays considerable morphological variability and distinct anatomical relationships.
- These quantitative findings can inform LAA trans-catheter occlusion and catheter ablation strategies.
Objective:
To investigate quantitatively the morphology, anatomy and function of the left atrial appendage (LAA) and its relation with adjacent structures.
Materials And Methods:
A total of 860 patients (533 men, 62.0%, age 55.9±10.4 year) who had cardiac multidetector computed tomography angiography from May to October 2012 were enrolled for analysis.
Results:
Seven types and 6 subtypes of LAA morphology were found with Type 2 being the most prevalent. Type 5 was more significantly (P<0.05) present in women (8.0%) than in men (4.2%). LAA orifice was oval in 81.5%, triangular in 7.3%, semicircular in 4%, water drop-like in 3.2%, round in 2.4% and foot-like in 1.6%. The LAA orifice had a significantly greater (P<0.01) major axis in men (24.79±3.81) than in women (22.68±4.07). The LAA orifice long axis was significantly (P<0.05) positively correlated with the height, weight and surface area of the patient. The LAA morphology parameters displayed strong positive correlation with the left atrium volume, aortic cross area long axis or LSPV long axis but poor correlation with the height, weight, surface area and vertebral body height of the patients. Four types of LAA ridge were identified: AI, AII, B and C with the distribution of 17.6%, 69.9%, 5.9% and 6.6%, respectively. The LAA had a significantly (P<0.05) greater distance from its orifice to the mitral ring in women than in men. The LAA had two filling and two emptying processes with the greatest volume at 45% phase but the least volume at 5% phase. The LAA maximal, minimal and emptying volumes were all significantly (P<0.05) positively correlated with the body height, weight and surface area, whereas the LAA ejection fraction had an inverse correlation with the LAA minimal volume but no correlation with the maximal volume.
Conclusion:
The LAA has substantially variable morphologies and relation with the adjacent structures, which may be helpful in guiding the LAA trans-catheter occlusion or catheter ablation procedures.
