Left atrial size--another differentiator for cardiac amyloidosis

Area of Science:

• Cardiology
• Medical Imaging
• Infiltrative Cardiomyopathy

Background:

• The classic "sparkled" echocardiographic sign of cardiac amyloidosis is less apparent with modern harmonic imaging.
• Dilated atria in patients with normal-sized ventricles may indicate cardiac amyloidosis.

Purpose of the Study:

• To evaluate atrial dilatation as a potential visual marker for cardiac amyloidosis.
• To differentiate cardiac amyloidosis from left ventricular hypertrophy using echocardiographic findings.

Main Methods:

• Retrospective analysis of echocardiograms from patients with biopsy-proven cardiac amyloidosis and hypertension.
• Patient groups were matched for left ventricular wall thickness, age, and sex (36 patients each).

Main Results:

• Cardiac amyloidosis patients exhibited significantly larger left atrial areas (29 cm² vs. 19 cm²) and volumes (100 cm³ vs. 55 cm³) compared to the hypertension group.
• A left atrial volume of 69 cm³ demonstrated 85% sensitivity and specificity for detecting amyloidosis (AUC 0.915).

Conclusions:

• Atrial dilatation is a reliable visual marker for identifying cardiac amyloidosis.
• This echocardiographic finding provides a simple method to distinguish cardiac amyloidosis from left ventricular hypertrophy.