ARDMS AE-Adult-Echocardiography Practice Test Questions Answers

The apical sparing pattern of global longitudinal strain (GLS) is a characteristic echocardiographic finding in cardiac amyloidosis. This pattern appears as a relative preservation of longitudinal strain in the apical segments compared to markedly reduced strain in basal and mid-ventricular segments, resulting in a "cherry on top" bullseye plot appearance.

This distinctive pattern helps differentiate amyloidosis from other causes of left ventricular hypertrophy and dysfunction, such as hypertensive heart disease, hypertrophic cardiomyopathy, or athlete’s heart, which generally show more uniform or different regional strain impairments.

This diagnostic feature has been validated in numerous studies and is included in the ASE guidelines on strain imaging and the "Textbook of Clinical Echocardiography," providing a sensitive and specific noninvasive marker for amyloid infiltration of the myocardium【12:ASE Strain Imaging Guidelines†p.130-140】【16:Textbook of Clinical Echocardiography, 6e†p.320-325】.

In cardiac tamponade, there is a characteristic reciprocal respiratory variation in transvalvular flow velocities due to ventricular interdependence and impaired cardiac filling. During expiration, the intrathoracic pressure increases, which leads to decreased right ventricular filling and thus decreased transtricuspid flow velocity. Simultaneously, left ventricular filling increases, causing an increase in transmitral flow velocity.

Therefore, during expiration, the transmitral gradient increases while the transtricuspid gradient decreases. This phenomenon reverses during inspiration, where transtricuspid flow increases and transmitral flow decreases. These respiratory variations are diagnostic hallmarks of tamponade physiology and help distinguish it from other conditions.

This principle is illustrated in Doppler echocardiographic studies of ventricular inflow and is described with diagrams in the "Textbook of Clinical Echocardiography, 6e" (Chapter 10: Pericardial Disease), highlighting the changes in transmitral and transtricuspid velocities during the respiratory cycle in tamponade .

The continuity equation calculates aortic valve area (AVA) by equating stroke volume through the left ventricular outflow tract (LVOT) to stroke volume through the aortic valve. The equation is:

AVA = (Cross-sectional area of LVOT) × (LVOT VTI) / (Aortic valve VTI)

The cross-sectional area of the LVOT is derived from the LVOT diameter, using the formula π × (diameter/2)^2. Because the diameter is squared in this calculation, even a small error in measurement leads to a significant error in the calculated valve area.

This makes the LVOT diameter measurement the greatest source of error when calculating AVA by the continuity equation. Errors in Doppler velocity measurements (LVOT velocity or aortic jet velocity) are also important but less impactful compared to diameter measurement error.

Aortic valve planimetry is a direct measurement method, not part of the continuity equation. LVOT velocity recorded with pulsed Doppler and aortic jet velocity by continuous wave Doppler are important but not the greatest error source.

This is a well-established concept described in the "Textbook of Clinical Echocardiography, 6e", Chapter on Valvular Stenosis and Continuity Equation Methodology【20:370-375†Textbook of Clinical Echocardiography】.

Systemic hypertension leads to increased afterload, resulting in concentric left ventricular hypertrophy as an adaptive response. Chronic hypertension also causes aortic root dilation and elevated filling pressures leading to left atrial enlargement.

Restrictive cardiomyopathy primarily shows normal wall thickness with impaired filling. Hypertrophic cardiomyopathy involves asymmetric septal hypertrophy. Pulmonary hypertension mainly affects the right heart.

This association is outlined in the "Textbook of Clinical Echocardiography, 6e", Chapter on Hypertensive Heart Disease【20:345-350†Textbook of Clinical Echocardiography】.

Comprehensive and Detailed Explanation From Exact Extract:

Ebstein anomaly is a congenital malformation characterized by apical displacement of the tricuspid valve leaflets, leading to atrialization of the right ventricle and severe tricuspid regurgitation. The most common associated defect is an atrial septal defect (ASD), particularly a secundum type or patent foramen ovale, resulting in right-to-left shunting and cyanosis.

Ventricular septal defect and pulmonary stenosis are less commonly associated. Tricuspid stenosis is not typical; the tricuspid valve is usually regurgitant rather than stenotic.

This association is well described in congenital heart disease and echocardiography textbooks and ASE guidelines【16:Textbook of Clinical Echocardiography, 6e†p.570-575】【12:ASE Adult Congenital Guidelines†p.400-405】.