NPPA-Associated Atrial Dilated Cardiomyopathy

Figures

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  Figure 1. Pedigree of the Proband Affected by ADCM Due to a Homozygous NPPA c.449G>A (p.Arg150Gln) Mutation (++) Both parents (I:1 and I:2) are deceased; clinical history suggests maternal chronic heart failure. The proband's 2 sisters (II:1 and II:2) are clinically unaffected and chose not to have genetic testing. Her brother (II:3) carries a pacemaker, but genetic status is unknown. The proband's 2 sons (III:1 and III:2) are heterozygous carriers of the NPPA variant (+−) and are asymptomatic with no signs of ADCM. Symbols are as follows: arrow = proband, squares = males, circles = females, diagonal line = deceased, solid fill = affected, shaded square = unclear cardiac phenotype, red symbols = NPPA genotype. ADCM = atrial dilated cardiomyopathy.

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  Figure 2. Baseline 12-Lead Electrocardiogram Showing Absence of P Waves and Atrial Electrical Activity, Consistent With Atrial Standstill The rhythm is a regular junctional escape rhythm at 40 beats/min.

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  Figure 3. Follow-Up 12-Lead Electrocardiogram of the Proband Demonstrating a Ventricular Rhythm Driven by a His-Bundle Pacemaker Operating in VVIR Mode Atrial electrical activity remains absent, consistent with permanent atrial standstill.

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  Figure 4. 2-Dimensional Transthoracic Echocardiography, Apical 4-Chamber View of the Proband, Showing Marked Biatrial Enlargement With Preserved Biventricular Size and Systolic Function

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  Figure 5. Parasternal Long-Axis Transthoracic Echocardiographic View of the Proband Showing a Markedly Enlarged Left Atrium, With an Anteroposterior Diameter Measuring 54 mm