CCI RCS Adult Echo flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Normal LV ejection fraction

ASE guidelines define normal left ventricular ejection fraction as 52-72 percent in men and 54-74 percent in women; values below these ranges indicate systolic dysfunction.

Left anterior descending territory

The LAD supplies the anterior left ventricular wall, the anterior two-thirds of the septum, and the apex, so occlusion typically produces anteroseptal and apical wall motion abnormalities.

Cardiac output formula

Cardiac output equals heart rate multiplied by stroke volume, normally about 4-8 liters per minute; cardiac index divides output by body surface area to give 2.5-4.0 liters per minute per square meter.

Aortic valve cusps

The normal aortic valve has three cusps named for the coronary arteries they overlie: the right coronary cusp, the left coronary cusp, and the non-coronary cusp.

Isovolumic contraction phase

During isovolumic contraction the mitral and aortic valves are both closed while ventricular pressure rises rapidly; no blood is ejected during this brief phase of the cardiac cycle.

Normal right ventricular systolic pressure

Resting right ventricular systolic pressure is normally about 15-30 mmHg and is estimated as four times the square of the peak tricuspid regurgitant velocity plus right atrial pressure.

Propagation speed in tissue

Ultrasound is assumed to travel through soft tissue at 1540 meters per second, the constant scanners use to convert echo return time into displayed depth.

Axial resolution definition

Axial resolution is the ability to separate two reflectors along the beam path and equals spatial pulse length divided by two; higher frequency and fewer cycles per pulse improve it.

Nyquist limit

The Nyquist limit is half the pulse repetition frequency; Doppler shifts exceeding it alias and appear as flow in the opposite direction or wrapped to the other side of the scale.

Doppler equation

Doppler shift equals two times transmitted frequency times blood velocity times the cosine of the intercept angle, divided by the propagation speed of 1540 meters per second.

Mechanical index

Mechanical index estimates cavitation risk and equals peak negative pressure divided by the square root of frequency; ALARA practice keeps it at or below 1.9.

Parasternal long-axis view

This view displays the right ventricular outflow tract, aortic root, left ventricle, mitral valve, and left atrium, and is used for left ventricular dimension and aortic root measurements.

Apical four-chamber view

Obtained with the transducer at the apical impulse, this view shows both atria and both ventricles with the mitral and tricuspid valves and is the primary view for comparing chamber sizes.

Apical two-chamber view

This view shows the left atrium and left ventricle with the anterior and inferior walls, and together with the four-chamber view provides the biplane Simpson volume measurement.

Suprasternal notch view

Placement of the transducer in the suprasternal notch images the aortic arch, its three great vessel branches, and the proximal descending thoracic aorta.

End-diastolic measurement timing

Chamber dimensions and wall thickness are measured at end-diastole, defined as the onset of the QRS complex on the simultaneously recorded electrocardiogram.

Severe aortic stenosis criteria

Severe aortic stenosis is defined by a peak velocity of at least 4 meters per second, a mean gradient of at least 40 mmHg, and a valve area of 1.0 square centimeter or less.

Hypertrophic cardiomyopathy features

Hypertrophic cardiomyopathy shows asymmetric septal thickening, systolic anterior motion of the mitral leaflet, and a late-peaking dagger-shaped LVOT velocity when dynamic obstruction is present.

Cardiac tamponade signs

Tamponade shows a moderate to large effusion with right atrial systolic collapse, right ventricular diastolic collapse, inferior vena cava plethora, and more than 25 percent respiratory variation in mitral inflow.

Constrictive pericarditis findings

Findings include pericardial thickening, septal bounce, annulus reversus with medial e-prime exceeding lateral e-prime, and more than 25 percent respiratory variation in mitral inflow velocities.

Most common congenital heart defect

Ventricular septal defect is the most common congenital heart defect diagnosed at birth, while bicuspid aortic valve is the most common congenital cardiac anomaly in the general population.

Tetralogy of Fallot components

Tetralogy of Fallot consists of a ventricular septal defect, an overriding aorta, right ventricular outflow tract obstruction, and consequent right ventricular hypertrophy.

Modified Bernoulli equation

Pressure gradient equals four times the square of peak velocity, so a jet peaking at 4 meters per second corresponds to a 64 mmHg gradient across the valve.

Continuity equation

Aortic valve area equals the LVOT cross-sectional area multiplied by the LVOT velocity-time integral, divided by the aortic valve velocity-time integral, reflecting conservation of flow.

PISA method

Effective regurgitant orifice area equals two pi times the radius squared times the aliasing velocity, divided by the peak regurgitant velocity, derived from the proximal flow convergence shell.

Pressure half-time for mitral area

Mitral valve area in square centimeters is approximated as 220 divided by the pressure half-time in milliseconds; a half-time of 220 ms corresponds to an area of 1.0 square centimeter.

Stroke volume from LVOT

Stroke volume equals the LVOT cross-sectional area, calculated as 0.785 times the diameter squared, multiplied by the LVOT velocity-time integral obtained by pulsed wave Doppler.

E over e-prime ratio

The ratio of mitral E velocity to tissue Doppler e-prime velocity estimates left atrial pressure; values below 8 suggest normal filling pressures and above 14 suggest elevation.

ALARA principle

As Low As Reasonably Achievable means keeping acoustic output, mechanical and thermal indices, and examination time at the minimum needed to obtain diagnostic information.

TEE fasting requirement

Patients typically fast six to eight hours before transesophageal echocardiography to reduce aspiration risk; conscious sedation, monitoring, and documentation of consent are required.

TEE contraindications

Esophageal stricture, esophageal varices, recent esophageal or gastric surgery, and perforated viscus are contraindications to transesophageal echocardiography; an uncooperative patient is a relative caution.

High-level disinfection

Transesophageal probes contact mucous membranes and are semi-critical devices, so they require high-level disinfection after each patient rather than simple cleaning or low-level disinfection.