Purpose
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and affects about 1-2% of general population.
It increases mortality and causes life quality decrease.
The myocardium of right and left atria (RA,
LA) is a substrate for atrial fibrillation.
Atrial fibrillation is accompanied by atrial electrical and structural remodeling .
The morphologic studies showed that atrial structural remodeling is expressed as atrial enlargement and walls thinning on the background of inflammation and fibrosis sites in myocardium.
And these changes may be found in both...
Methods and Materials
PubMed was searched for articles concerning LGE MRI in patients with atrial fibrillation and MR-images automated analysis. Search terms and combinations included LGE MRI; atrial fibrillation; histology; automated scar detection; automated fibrosis detection. Important factors and techniques were selected,
evaluated and subsequently submitted.
Results
Factors of poor quality LGE MR-images of atria:
Solutions:
Thin walls
High resolution scan – use of 3D acquisition; Special cardiac cycle ECG synchronization
Motion in respiratory cycle
Respiratory synchronization
Motion in cardiac cycle
Special cardiac cycle ECG synchronization
Fat
Fat saturation
Acquisition Time
Use fast imaging technologies
Factors of mistakes in atrial LGE MRI image analysis:
Solutions:
Image artifacts
Development new MR-pulse sequences for image aquisition
Thin walls
Performing manual,
semi-automated or automated atrial segmentation
Performing Automatic scar and fibrosis detection
Low size of...
Conclusion
LGE MRI of atria is a new approach to perform qualitative and quantitative analysis of fibrotic structures in atrial wall.
The advance of the method is noninvasiveness and automated algorithms of fibrosis/scar detection allow higher speed analysis and satisfactory reproducibility of results.
Nowadays this method can provide information about structural remodeling of atria in each particular patient and make the individual decision regarding techniques of invasive treatment.
Nevertheless,
the methods of both atrial walls image acquisition and automatic fibrosis/scar definition are still controversial and need...
References
ESC 2010 Guidelines for the Management of Patients With Atrial Fibrillation: The Task Force for the Management of Atrial Fibrillation of the European Society of Cardiology (ESC).
Developed with the special contribution of the European Heart Rhythm Association (EHRA).
European Heart Journal (2010) 31,
2369–2429.
Platonov PG,
Mitrofanova LB,
Orshanskaya V.
et al.
Structural abnormalities in atrial walls are associated with presence and persistency of atrial fibrillation but not with age.
J Am Coll Cardiol.
2011 Nov 15; 58(21):2225-32.
Bondarenko O.,
Beek A.M.,
Hofman M.B....