Restricted Left Atrial Dilatation Can Visually Differentiate Cardiac Amyloidosis from Hypertrophic Cardiomyopathy

Figures

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  Figure 1. Visual assessment of LA dilatation grade in an apical four‐chamber view. The left and right panels show still images indicating the minimum and maximum LA volumes for scoring LA dilatation grade. (A) Preserved LA dilatation (Grade 1), (B) abnormal LA dilatation (Grade 2), and (C) restricted LA dilatation (Grade 3). LA, left atrial.

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  Figure 2. Left atrial dilatation grade in hypertrophic cardiomyopathy and cardiac amyloidosis. (A) The number of LA dilatation grade in patients with HCM and CA. Patients with CA had a higher LA dilatation grade than those with HCM. (B) Plots of LA emptying fraction according to LA dilatation grade. Each mean value with 95% confidence intervals. When the LA dilatation grade was higher, the LA emptying fraction was lower. CA, cardiac amyloidosis; HCM, hypertrophic cardiomyopathy; LA, left atrial.

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  Figure 3. Discriminatory ability of LA structural and functional parameters in patients with hypertrophic cardiomyopathy and cardiac amyloidosis. A receiver operating characteristic curve analysis was performed to assess the discriminatory ability of LA structural and functional parameters. Left atrial dilatation grade and emptying fraction had higher AUC values than LA reservoir strain and volume index. AUC, area under the curve; LA, left atrial.

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  Figure 4. Representative case of cardiac amyloidosis. An 80‐year‐old man with CA. In an apical four‐chamber view (A: left panel, still image showing the minimum LA volume; right panel, image showing the maximum LA volume), LA dilatation identified via visually assessment was graded 3 (restricted). The maximum and minimum LA volumes were 38 and 35 mL, respectively. The LA emptying fraction was low, 8%. CMR imaging revealed late gadolinium enhancement in the LA wall (B, arrows). CA, cardiac amyloidosis; LA, left atrial; CMR, cardiac magnetic resonance.

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  Figure 5. Impact of restricted LA dilatation on the occurrence of cardiac event. The Kaplan–Meier curves showed that patients with LA dilatation Grade 3 had a higher incidence of cardiac event than those with LA dilatation Grades 1 or 2. LA, left atrial.