Echocardiography

Relevant Social Security Medical Listings

  • Listing 4.02 Chronic Heart Failure (Adults)
  • Listing 104.02 Chronic Heart Failure (Children)
  • Listing 4.04 Ischemic Heart Disease (Adults)
  • Listing 4.06 Congenital Heart Disease (Adults)
  • Listing 104.06 Congenital Heart Disease (Children)
  • Listing 4.09 Heart Transplants (Adults)
  • Listing 104.09 Heart Transplants (Children)
  • Listing 104.13 Chronic Rheumatic Fever or Rheumatic Heart Disease (Children)
  • Listing 4.10 Aneurysms of the Aorta or Major Branches (Adults)

Type

Objective/Ultrasound (Heart)

Purpose

  • Diagnose abnormalities of heart valves.
  • Diagnose abnormalities of wall motion and chamber size (especially the left ventricle) during contraction (systole) and relaxation (diastole) of the heart.
  • Diagnose thickness (hypertrophy) of the heart wall muscle.
  • Diagnose pericardial effusion (excessive fluid accumulation between the pericardial membrane and the heart).
  • Diagnose cardiac tumors.
  • Diagnose congenital heart disease.
  • Diagnose occlusive disease of the coronary arteries.

Contraindications

Contraindications to transesophageal echocardiography (TEE) include obstruction of  the esophagus, esophageal varices, or esophageal stenosis. There are no contraindications to other types of echocardiography, other than the common-sense one that an ultrasound transducer shouldn’t be placed on an open wound.

Technique

The patient lies supine. A transducer is placed on the chest after application of a gel; the location of the transducer is moved and angled to provide the best view of the cardiac structure of interest. The transducer produces high-frequency (ultrasonic) waves of several million cycles per second that reflect from cardiac structures. The returning sound waves are picked up by a sensor and constructed (computed) into an image that can be seen on a video monitor and also printed out. This usual type of echocardiography is more technically termed transthoracic echocardiography (TTE), because the study is done by sending ultrasonic waves through the chest wall. Other than transesophageal echocardiography (TEE) discussed under “Comments” below, all the other variations discussed are transthoracic.

No special patient preparation is needed. If multiple modes of echocardiography are required, as is often the case, the test requires about 1.5 hours to complete.

Complication

Transesophageal echocardiography requires more patient preparation and has risks not associated with other types of echocardiography, because of the need to introduce the ultrasound transducer into the esophagus. An intravenous line is placed so that a sedative can be given, and as a route for the administration of other drugs should a complication occur. Possible complications include cardiac arrhythmias or bleeding from the esophagus. Adequate resuscitation and monitoring equipment must be available during TEE. Usually, TEE can be done without any adverse consequences, even in elderly patients. The risk of death is exceedingly small, probably no greater than 1 in 10,000.

Interpretation

General

Heart Valves

Abnormal heart valves may be too narrow (stenosis), that can’t close tightly (insufficiency)[1], or infected (endocarditis); artificial heart valves may break or malfunction. The four heart valves are the tricuspid, mitral, pulmonary, and aortic. The most frequently diseased are the aortic and mitral valves.

The aortic valve normally has a cross-sectional area of 2 to 3 cm2, and stenosis is severe if less than 1.0 cm2. Aortic valve areas less than 0.5 cm2 may be incompatible with life. Valve area should not be confused with valve area indexes that take body size into account by including body surface area. For example, as stated above, while an aortic valve area of less than 1.0 cm2 is considered severe, an aortic valve area index is severe when about 0.5 to 0.6 cm2 or less per square meter of body area (0.5 to 0.6 cm2/m2). The index method has the advantage of compensating for very small or large individuals.

See image “Fig. 4.23-1 – Echocardiography[2]” on the CD-ROM in the Chapter 4 folder located in the Graphics folder.

Aortic stenosis is common and the following guidelines are relevant:

Normal aortic valve: (a) Area greater than 2.0 cm2; (b) peak and mean pressure gradients across valve 0 mm Hg; (c) peak blood velocity through valve 1 – 2 meters/sec.

Mild aortic stenosis: (a) Area 1.3 – 2.0 cm2; (b) mean gradient less than 15 mm Hg, peak gradient 16 – 35 mm Hg; (c) peak blood velocity 2.1 – 3 meters/sec.

Moderate aortic stenosis: (a) Area 0.8 – 1.2 cm2; (b) mean gradient than 15 – 30 mm Hg, peak gradient 36 – 64 mm Hg; (c) peak blood velocity 3.1 – 4 meters/sec.

Severe aortic stenosis: (a) Area less than about 0.8 – 1.0 cm2; (b) mean gradient greater than 50 mm Hg, peak gradient greater than 64 mm Hg; (c) peak blood velocity greater than 4 meters/sec.

Note that adjectives “normal,” “mild,” “moderate,” and “severe” convey only general information and should not be presumed to represent particular values in any medical records. For example, some sources use “severe” to mean an area less than 1.0 cm2 while others would apply the same adjective at less than 0.8 cm2.

Normal mitral valve area is 4 to 6 cm2; congestive heart failure may develop with area below about 1.5 cm2. Mitral valve areas below 1.0 cm2 may be associated with even more severe heart failure, as well as high blood pressure in the pulmonary arteries (pulmonary hypertension).

The tricuspid valve normally has an area of about 7.0 cm2. Tricuspid valve stenosis becomes significant when the area drops to about 1.5 cm2, and is severe when less than 1.0 cm2. Tricuspid valve disease is unusual in adults[3], but is frequently involved in congenital heart disease. At birth it is about 0.5 cm2 and increases in size with body growth.

In regard to heart valves in general, it should not be thought that determination of the clinical severity valve narrowing is as simple as measuring valve size by an echocardiogram or other test such as Cardiac Catheterization, §4.13. Pressure gradients across the valve, as well as other medical factors determine clinical severity.

Left Ventricular Chamber Size

Many diseases of heart muscle (cardiomyopathies), heart attacks (myocardial infarction, MI), and inadequate blood flow to the heart muscle (coronary artery disease {CAD}) may affect the heart’s ability to contract normally. By measuring chamber sizes during contraction and relaxation of the heart muscle, especially of the main pumping chamber (left ventricle), the overall efficiency of the heart in pumping blood can be calculated. When providing measurements of left ventricular chamber size, echocardiographic reports are referring to the space that makes up the left ventricle and do not include the thickness of the muscle walls surrounding the left ventricle.

In echocardiographic reports, the most important chamber size is the left ventricular internal dimension in diastole (LVIDD or LVIDd). The margin of error of two-dimensional echocardiograms is about 0.2-0.3 cm (2-3 millimeters, mm). The normal range of left ventricular size varies a little between reporting authorities, but is about 4.2 to 5.5 cm in adults, with a mean (average) of about 5.0 cm. Significantly abnormal enlargement is probably present when the LVIDD exceeds 5.0 cm, and characteristic of an enlarged (dilated) poorly functioning left ventricle.

A number known as the left ventricular ejection fraction (LVEF) is the percentage of blood the left ventricle pumps with each beat of the heart, and is frequently used in evaluating performance of the heart. A normal LVEF is 55 – 65%.

Wall Motion Abnormalities

Slowed movement in an area of heart muscle (hypokinesis) and absence of movement (akinesis) are indicative that area is not receiving adequate blood flow; these motion abnormalities usually occur when there is decreased blood flow (ischemia) or scarring from a heart attack and are called regional wall motion abnormalities. Regional wall motion is usually graded by standard criteria as follows: 1 = normal ( = or > 5 mm endocardial excursion[4] and = or > 25% systolic thickening[5]); 2 = hypokinetic ( < 5 mm endocardial excursion, < 25% systolic thickening); 3 = akinetic (no endocardial excursion); and 4 = dyskinetic (paradoxical systolic outward motion or expansion).

Both ischemia and heart attacks are usually caused by coronary artery disease.[6] If the damage to the heart muscle walls is sufficiently severe, heart failure will result. Heart failure is usually congestive heart failure (CHF) and is diagnosed by physical examination[7] or chest x-rays[8]. However, echocardiograms are useful in determining the nature and extent of damage causing the heart failure, as well as the response to treatment.

Ventricular Hypertrophy

Ventricular hypertrophy is thickening of the heart muscle walls, and therefore is associated with increased size and weight of the heart. However, ventricular hypertrophy does not imply that the ventricular chambers are enlarged. Chronic high blood pressure causes left ventricular hypertrophy as do some other diseases such as hypertrophic cardiomyopathy.

Tumors

The heart’s small chambers are the left and right atria, in contrast to the much larger main pumping chambers that are the left and right ventricles. Cardiac tumors such a left atrial myxoma handing on a stalk can be visualized by echocardiography.

Congenital Heart Disease

Since congenital heart disease may result in a large variety of structural abnormalities of that organ, echocardiography is a valuable diagnostic tool, especially in fetal imaging, infants, and children.

Comments

The are several types of echocardiography.

A. Transesophageal Echocardiography (TEE)

TEE is particularly useful in imaging artificial (prosthetic) valves and infection of the heart (endocarditis). TEE has a sensitivity of at least 90% in detecting vegetations (lumps of infected material on heart valves), and is also useful in seeing local areas of infection near valves (abscesses).

Because the TEE transducer is closer to the heart than in transthoracic echocardiography and utilizes a higher frequency (5 megahertz vs 2.5 – 3.5 megahertz), it can provide better detection and evaluation of the severity of some congenital heart defects. These include patent foramen ovale (PFO)[9], masses in the aortic arch[10], and atrial septal aneurysm (ASA)[11]. Such congenital abnormalities are sometimes responsible for strokes that are otherwise cryptogenic, i.e., of unknown cause.

Cardiac blood clots (thrombi) usually form from stagnant blood in the atrial chambers of the heart can be pumped to the lungs from the right atrium (pulmonary emboli), or pumped to the brain from the left atrium (embolic stroke). Such stagnant blood is often caused by a cardiac arrhythmia known as atrial fibrillation. Blood clots forming in the left atrium frequently form on a structure called the left atrial appendage, then break off. Atrial appendage thrombi cannot be seen with TT echocardiography, but can be visualized with TEE.

Stagnant blood creates a spontaneous echo contrast (SPEC) appearing on TEE as a whirling smoke-like pattern, and has a strong association with intracardiac blood clots. Another abnormality that can be seen only with TEE is called valvular strands, which are short filaments attached to the aortic or mitral heart valves. The strands may be associated with blood clot material that can break off and embolize to the brain causing a stroke.

TEE can provide indirect information about the probability of having obstructive atherosclerotic fatty disease deposits in the coronary arteries of the heart. TEE can image the arch of the aorta. Atherosclerotic plaques forming inside the arch of the aorta involve the same general type of disease process as that obstructing blood flow in the coronary arteries. When there is no disease in the aortic arch, there is a very high negative predictive value of over 90% that disease is also absent from the coronary arteries. When disease is present in the aortic arch, the probability of coronary artery disease increases and may exceed a positive predictive value of 70% when risk factors of elevated serum cholesterol, hypertension, and diabetes mellitus are present; other risk factors may further increase positive predictive value. However, because of this relatively low positive predictive value, TEE aortic arch imaging is not a substitute for diagnostic studies that can definitively diagnose coronary artery disease such as cardiac catheterization or other direct imaging techniques of the coronary arteries. The principal value of TEE aortic arch imaging is in the high negative predictive value that a TEE image showing no atherosclerotic plaques is a good indicator that coronary artery disease is probably not present. A newer technique known as suprasternal harmonic imagining can non-invasively (transcutaneously) compliment TEE by showing aortic arch lesions that can be missed by TEE, with a positive predictive value of 91% and a negative predictive value of 98%. Suprasternal harmonic imaging is inadequate in about 16% of cases.

See also Dobutamine Stress Echocardiography (DSE), §4.21, for discussion of use of TEE in that procedure.

See also D. below, regarding 3-D echocardiography and TEE.

B. M-Mode Echocardiography

M-mode echocardiography is the oldest type and provides a one-dimensional image of cardiac structures; it is still helpful in imaging valves.

C. Two-Dimensional (2-D) Echocardiography[12]

Two-dimensional echocardiography has largely replaced the M-mode type, because it provides the better spatial resolution of a two-dimensional image thus allowing better visualization of the movement of heart structures.

D. Three-Dimensional (3-D) Echocardiography (3-D Dynamic Echocardiography)

Three-dimensional echocardiography provides images of cardiac structures more like normal visual experience, so that such images are easier to interpret than M-Mode or 2-D echocardiograms. The 3-D echocardiogram is gated, so that views are coordinated with the cardiac cycle of contraction and relaxation. 3-D echocardiography is particularly useful in diagnosing congenital heart disease in the fetus, infants, children, and adults that cannot be seen with 2-D echocardiography.

As of 2008, developments in real-time 3-D echocardiography can now provide unparalleled cardiac detail, particularly of the mitral valve; the other valves cannot be seen quite as well. However, the imaging is so much better than with 2-D studies, it will probably become the standard in a few years—thanks to the use of several thousand ultrasound probe elements, compared to the 64 elements used in the standard 2-D probe. Valvular stenoses, atrial septal defects (ASDs), ventricular septal defects (VSDs), and other common congenital abnormalities can be seen with a clarity that is much improved anatomically. This technology is a very significant advancement in TEE imaging.

E. Four-Dimensional (4-D) Echocardiography

Four-dimensional echocardiography is 3-D echocardiography producing movie-like images displayed in real time, rather than individual static 3-D images. In this sense, it is a further advancement over 3-D studies. The 4th dimension is represented by time. 4-D echocardiography is often referred to as “3-D echocardiography in real time,” which seems to have caught on as the preferred terminology for 4-D studies.

F. Doppler Echocardiography

a. Evaluation of blood flow through valves and shunts

Doppler echocardiography is particularly useful for evaluating the flow of blood within the heart, rather than images of the solid heart structures, and when performed are usually done after M-mode and/or 2-D echocardiography. Doppler echocardiograms provide information about the direction and velocity of blood flow through the various heart structures. This information can be further translated into volume and pressure data about blood flow, such as through an abnormal heart valve or through abnormal holes (shunts) inside the heart, using the equation P = 4V2 where P is the pressure gradient and V is the Doppler-derived blood velocity. Velocities of blood flow inside the heart vary with the location, and are somewhat higher in children than adults. Reference values for normal velocity ranges are available to cardiologists when interpreting echocardiograms. For example, the velocity of blood flow through the tricuspid valve is about 0.5 – 0.8 meters/second in children and about 0.3 – 0.7 meters/second in adults; the corresponding values for the mitral valve are about 0.8 – 1.2 and 0.4 – 1.3 meters/second respectively. Doppler echocardiography also is of value in calculating valve area.

In Example 2 below, aortic stenosis is reported with a transvalvular pressure gradient of 25 mm Hg. Using the above equation, the flow velocity through the aortic valve was about 2.5 meters/second, increased because of narrowing of the valve. In adults, the velocity of blood ejected from the left ventricle through the aortic valve into the aorta is normally in a range of about 0.7 – 1.0 meter/second. Using his judgment of the over-all findings, the interpreting cardiologist concluded that the aortic valvular stenosis was more severe than suggested by the Doppler measurement of the pressure gradient. This is also an example of the importance of informed medical judgment in addition to numbers obtained from test results.

Complex shunts are a common problem in congenital heart disease. The Doppler echocardiographic equipment can also be set to color-code the directional flow of blood, so that red represents flow away from the transducer and blue toward the transducer. Such color Dopplers are especially helpful in evaluating disease of heart valves through study of how blood flows through abnormally narrow or wide valves. Doppler echocardiography exists in two basic forms, both of which are usually performed. One is continuous wave Doppler and the other is pulsed wave Doppler. Continuous wave Doppler has the ability to detect high velocity flows, such as occurring through stenotic valves, but does not permit good localization of the flow. Pulsed wave Doppler can’t detect flows less than about 1.5 meters/second, but has the advantage of providing good resolution of the exact location of the flow being studied.

Since the heart lies behind the breastbone (sternum), echocardiographic imaging must be done by aiming the ultrasonic beam in behind the sternum by positioning the ultrasound transducer beside the sternum (parasternal view), below the sternum and ribs (subxiphoid and subcostal views), above the sternum (suprasternal view), or behind the heart through the esophagus (transesophageal view). The various standard views and images obtained with color Doppler are as follows:

Long axis parasternal: flow through the mitral valve and left ventricle through the aortic valve; useful in evaluating mitral and aortic insufficiency

Short axis parasternal: flow through the tricuspid valve and right ventricle through the pulmonic valve to the pulmonary artery

Subcostal view: flow through the mitral and tricuspid valves to the left and right ventricles respectively, i.e., flow through the left and right ventricular inflow tracts; useful for detecting and determining the severity of mitral and tricuspid insufficiency

Apical 4-chamber view: information similar to subcostal view

Apical 5-chamber view: flow through the outflow tract of the left ventricle, i.e., through the aortic valve; useful in detecting and determining the severity of aortic insufficiency

Suprasternal view: flow through the ascending aorta, aortic arch and descending aorta; useful for determining the severity of aortic stenosis

Transesophageal view:       See discussion of TEE above.

b. Evaluation of myocardial performance

An Index of Myocardial Performance (IMP), or Tei Index, has been used as a method of evaluating global left ventricular function during both systolic (contraction) and diastolic (relaxation) phases of left ventricular performance. The IMP is calculated with a simple formula, (a – b)/b, easily made from measurements on a Doppler echocardiogram. The letter “a” is the interval between the end and beginning of blood flow through the mitral valve, and “b” is the time it takes the left ventricle to eject its blood (LV ejection time) into the aorta when it contracts.

In determining the severity of heart disease, the LV ejection fraction (LVEF) is most often used to assess LV function. However, use of the LVEF is susceptible to error when, as is often the case, the left ventricle is not geometrically symmetrical. Thus, the IMP is potentially a more accurate means of evaluating the severity of various forms of cardiomyopathy, LV function after myocardial infarction, and LV function in congenital heart disease, than the LVEF.

One use of the IMP is to detect evidence of immune rejection of a heart transplant, as indicated by a change in the IMP; as rejection decreases the heart’s performance, the IMP will increase. An increase of IMP of 20% or more has a sensitivity and specificity of 90% for detecting a rejection process in a transplanted heart allograft.[13] For example, a transplanted heart might start off with an IMP of 0.77 and then increase to 1.3 as rejection progresses, or increase from 0.4 to 0.9. The IMP is a useful test because it may permit a decrease in the numbers of invasive endomyocardial biopsies needed to monitor the health of transplanted hearts.

Tissue Doppler echocardiography[14] is a modification of conventional Doppler echocardiography that may be used to objectively measure the function of the heart’s left ventricle by color coding the velocity of cardiac wall motion, so that different colors represent different velocities. Tissue Doppler echocardiography allows quantification of severity of cardiac wall motion abnormality.

IMP is not significantly affected by heart rate or blood pressure. However, IMP as measured by conventional Doppler echocardiography has a potential problem in that measurements are taken in two sequential heart cycles. That means that the IMP in patients with a lot of heart rate variability is susceptible to a small amount of error, because premature filling or ejection of blood will affect the interval measurements due to the changed amount of blood being moved. A modified IMP using tissue Doppler echocardiography solves this problem by taking simultaneous measurements during the same cardiac cycle. This modified IMP also correlates closely with the IMP done by conventional pulsed wave Doppler echocardiography, and provides an alternative form of measurement that is simple to make. A normal modified IMP is about 0.33 – 0.47. Abnormal values are higher.

Another use of tissue Dopplers is to diagnose early hypertrophic cardiomyopathy (HCM). In HCM, the heart’s muscle fibers cannot relax as quickly as normal during diastole—when the heart is between beats and filling with blood. The velocity at which myocardial fibers can relax in the early part of diastole is known as the Ea velocity. In HCM, there also is an increase in the left ventricular ejection fraction (LVEF). Using a diagnostic cut-off of an Ea velocity of less than 15 centimeters/second and LVEF of at least 68%, all cases of HCM can be identified with virtually 100% accuracy long before the disorder produces obvious hypertrophy of heart muscle. This is important because HCM is a serious disorder than can result in sudden death from cardiac arrhythmias during strenuous exertion.

G. Coronary Transthoracic Echocardiography

Coronary echocardiography involves two-dimensional (2-D) imaging and is a technique of visualization of the proximal 2 – 3 cm of the left coronary artery, which provides important blood flow to the heart (discussion of coronary arteries can be found in Cardiac Catheterization, §4.13). The value of this procedure is that it is safe and noninvasive, unlike cardiac catheterization. Coronary echocardiography has been of value in imaging congenital malformations of coronary arteries, and of determining the severity of coronary obstructive lesions. However, such transthoracic echocardiographic imaging of coronary arteries has not developed the degree of technical sophistication necessary to provide adequate images of more than a small portion of the left coronary artery as described above. Color Doppler transthoracic ultrasound has been used to evaluate the patency of the left anterior descending (LAD) coronary artery and major branches (perforators) after a heart attack. The sensitivity for detecting LAD patency has been reported to be 86%, specificity of 98%, and accuracy of 97% in this context. A more physiological measure of coronary blood flow can be obtained by determination of coronary fractional flow reserve (FFR) done during Cardiac Catheterization, §4.13 and by Coronary Flow Reserve (by Doppler), §4.17.1.

Coronary artery blood velocity is faster in younger individuals. As measured by TEE in healthy subjects ages 7 – 16 years, coronary blood velocity is about 34 ± 10 cm/sec in the left anterior descending, 27 ± 12 cm/sec in the left circumflex, and 30 ± 12 cm/sec in the right coronary artery.

H. Color Kinesis (CK) Echocardiography

Color kinesis (CK) echocardiography is a type of two-dimensional echocardiography that allows real-time visualization of ventricular wall motion abnormalities by layers of color-coding. For example, areas of dyskinetic wall motion are coded as having more red color than other grades of wall motion abnormality. However, in the presence of a left bundle branch heart block (LBBB), color kinesis may be unreliable in measuring the severity of wall motion abnormality. A 2-D CK echocardiogram, however, does not provide the wall motion velocity information as a tissue Doppler echocardiogram.

Examples

Example 1

M-Mode and Sector Echocardiogram

Patient: Male, age 63

Reason for Request: Edema.[15]

Aorta: The aorta is normal in size. Its anterior motion during systole is normal. There is no evidence of calcification[16] in the wall of the aorta.

Aortic Valve: There is calcium in the cusp[17] of the aortic valve and the cusp separation is mildly decreased. This would indicate mild aortic stenosis.

Left Atrium: The left atrium is normal in size.

Left Ventricular Function: The left ventricular ejection fraction was 70%.

Interventricular Septum: The interventricular septum[18] is of normal thickness and motion.

Left Ventricular Posterior Wall: The left ventricular posterior wall is of normal thickness and motion.

Mitral Valve: The mitral valve opens normally during diastole. There is no evidence of calcification in the valve. There is no evidence of mitral valve prolapse.[19] There is mitral annular calcification.[20]

Right Ventricle: The right ventricle appears normal in size.

Pericardium: The pericardium appears normal with no evidence of pericardial effusion.

Doppler Exam: Doppler examination of the aortic valve revealed a gradient of 12 – 15 mm Hg across the aortic valve.[21] There was no aortic regurgitation present. Examination of the mitral valve revealed mild mitral regurgitation.[22]

Final Impression: Abnormal echocardiogram.

1. Mild aortic stenosis.

2. Mild mitral regurgitation.

3. Mitral annular calcification.

Example 2

Echocardiogram

Patient:  Male, age 62, weight 163 lbs., height 71 inches

Aorta:  The aorta is of normal dimension. There is reduced anterior motion during systole.[13]

Aortic Valve:  The aortic valve is densely calcified and the valve appears immobile. Doppler study indicated only about a 25 mm Hg gradient across the valve, but I believe the angle theta[14] was excessive and therefore this is an underestimation of the gradient. There is 2 to 3+ aortic insufficiency.[15]

Left Atrium:  The left atrium is enlarged at 5 cm.

Left Ventricular Function:  Left ventricular function is reduced, and the estimated ejection fraction is in the 25 to 30 percent range.

Interventricular Septum:  The interventricular septum is hypokinetic but only about 1.2 cm thick.

Left Ventricular Posterior Wall:  The posterior wall is thickened to a similar degree and is also hypokinetic.

Mitral Valve:  The mitral valve annulus is calcified. There is a 1 to 2+ mitral regurgitation and there is some calcification of the mitral leaflets but there is no evidence of significant mitral stenosis with a normal valve area.

Right Ventricle:  Right ventricular chamber size is normal.

Pericardium:  There is no evidence of pericardial effusion.

Final Impression:

1. Moderate aortic stenosis by Doppler, although I believe the appearance of the valve is more consistent with severe stenosis.

2. Moderately severe aortic insufficiency.

3. Mild to moderate mitral regurgitation with no evidence of mitral stenosis.

4. Dilated, poorly contractile left ventricle with ejection fraction in the 20 to 30 percent range.

5. Moderate left atrial enlargement.

Example 3

Transesophageal Echocardiogram

Indications:  To evaluate for the severity of the patient’s mitral regurgitation and feasibility for mitral valve repair. Also evaluate for severity of aortic valve regurgitation and need for aortic valve repair.

Premedications:  None. The patient was under general anesthesia.

Complications:  None

Study:  A 2-D echocardiogram with color flow mapping was performed using an omni-plane probe. Routine trans-gastric[16] and transesophageal images were obtained. The study was technically adequate.

The aortic valve is tricuspid[17] and minimally sclerotic[18] without stenosis. Mild aortic regurgitation is present. The posterior mitral leaflet is mildly calcified and fixed and the anterior mitral leaflet is minimally calcified but shows adequate diastolic excursion with evidence of diastolic doming as well as systolic prolapse. Findings are consistent with rheumatic mitral valve disease without stenosis. There is moderate to severe (3+/4) mitral regurgitation with the regurgitant jet being directed posteriorly. The tricuspid and pulmonic valves are normal.

The left ventricle is normal in size and wall thickness with lower limits of normal contraction or minimal global hypokinesis. LV ejection fraction is estimated at 50%. The left atrium is markedly dilated and the right atrium is minimally dilated. The right ventricle is normal. No intra-cardiac (including left and right atrial appendage) clots or masses are noted. The atrial septum is intact with no evidence of shunt across. The aortic root and pulmonary artery are normal. No pericardial effusion is present.

Impression:  A technically adequate and abnormal transesophageal echocardiogram.

Abnormal Aortic Valve:  tricuspid and mildly sclerotic without stenosis. Mild aortic regurgitation is present.

Abnormal Mitral Valve:  Mildly calcified and fixed posterior leaflet with evidence of diastolic doming but good diastolic excursion. Findings are consistent with rheumatic mitral valve disease without significant stenosis. Moderate to severe (3+/4) mitral regurgitation is present. There is evidence of mild systolic prolapse of the anterior leaflet with the mitral regurgitation jet being directed posteriorly.

Abnormal Left Atrium:  Markedly dilated left atrium and minimally dilated right atrium.

Abnormal Left Ventricle:  Normal in size and wall thickness with lower limits of normal contraction or minimal global hypokinesis. LV ejection fraction estimated at 50%.

Example 4

Echocardiogram

Clinical Diagnosis:  Bilateral arm pain, shortness of breath, dizziness.

Type of Study:  2-D and M-mode echocardiogram with pulse wave, continuous wave and color flow Doppler evaluation.

M-Mode:  The M-mode echocardiogram demonstrates left ventricular end diastolic dimension near the upper limit of normal at 55 mm. The aortic root[19] is at the upper limit of normal at 37 mm with normal left atrial dimension. Left ventricular function well maintained. Mitral valve with normal E to F slope and rules out diagnostic evidence of prolapse; no other abnormality. Aortic valve grossly unremarkable, but suboptimally visualized. Otherwise unremarkable M- mode study.

2-D Echo:  2-D echocardiographic images were obtained in parasternal long and short axis, as well as apical 2, 4, and 5 chamber and subcostal views. The left atrium is of normal dimension, otherwise unremarkable. The mitral valve demonstrates grossly normal texture and mobility. The left ventricle demonstrates an end diastolic dimension near the upper limit of normal with mild global reduction in systolic function with an estimated ejection fraction of 54%. No regional wall motion abnormality is detected. The aortic root is near the upper limit of normal for size, otherwise unremarkable. The aortic valve demonstrates normal texture and mobility when visualized. The right-sided structures are unremarkable. There is no evidence of pericardial effusion.

Doppler:  Color flow Doppler demonstrates a trace of mitral, aortic, tricuspid and pulmonic insufficiency. Pulse and continuous wave Doppler across the mitral valve inflow demonstrates preservation of normal E to A ratio and detects a trace of mitral insufficiency. No  significant aortic valvular gradient or hemodynamically significant insufficiencies were identified.

Conclusion:

1. Preserved left ventricular function (LVEF = 54%) with left ventricular end diastolic dimension near the upper limit of normal.

2. Trace of mitral and aortic incompetence with aortic root dimension near the upper limit of normal.

3. Trace of tricuspid and pulmonic insufficiency within physiologic range for normal.

4. Clinical correlation recommended:  consider underlying hypertensive cardiovascular disease.

5. No regional wall motion abnormality is detected, and there is no diagnostic evidence to suggest sarcoidal[20] or ischemic heart disease.

Example 5

Transesophageal Echocardiogram

Preop Diagnosis:  Thrombus to mesenteric arteries with subsequent ischemic colon.[21]

Postop Diagnosis:  Same.

Procedure:  Transesophageal echocardiogram.

Description of Procedure:  After appropriate permits were signed, the patient was brought to the Cardiology Department and prepped in the usual manner. The patient received IV sedation as well as topical anesthesia to the oropharynx. After appropriate sedation, the transesophageal echo probe was advanced to multiple levels of the esophagus where multiple images of the heart were obtained. The patient tolerated the procedure well. No difficulties or complications were associated with the procedure. IV sedation was reversed by appropriate medications. The patient was recovered in the Cardiology Department. There were no immediate complications.

Impression:

1. Left ventricle – normal contraction.

2. Left atrial appendage – no thrombus identified.

3. Foramen ovale – closed.[22]

4. Mitral leaflets were thickened.

5. Mild to moderate aortic insufficiency verified.

Example 6

Two-Dimensional and M-Mode Echocardio-gram with Doppler

Interpretation:

LV Diastolic Diameter: 4.4 cm (3.7-5.6)

LV Systolic Diameter: 2.7 cm

Aortic Root Diameter: 3.3 cm (2.3-3.7)

Left Atrial Diameter: 3.1 cm (but I think that is wrong) (1.9-4.0)

The left ventricle is not dilated. There is normal left ventricular systolic function with ejection fraction greater than 55%. The mitral valve is markedly abnormal with thickening and calcification of both mitral leaflets and apparent effusion of the posterior mitral leaflet with limited mobility of the posterior mitral leaflet. There is at least moderate mitral stenosis. The left atrium is significantly dilated. The aortic valve is unremarkable. The right atrium is dilated. The right ventricle is normal in dimension.

Doppler examination showed a peak aortic velocity of 1.3 m/sec. Peak mitral velocity is 1.8 m/sec. The pressure half-time was measured at 128 m/sec, but I think that this is in error, and I think it is probably longer than that. The calculated mitral valve area based on those erroneous measurements is 1.7 sq. cm. There was mild tricuspid regurgitation detected by color-flow imaging. The peak tricuspid regurgitant velocity was 3.2 m/sec, suggesting peak right ventricular systolic pressures of approximately 45-50 mm Hg.

Impression:

1.  Normal left ventricular systolic function.

2.  Moderately severe mitral stenosis with fusion of the posterior mitral leaflet.

3.  Mild tricuspid regurgitation with moderate pulmonary hypertension.

4.  The patient was in a sinus rhythm during this study.

Conclusion

No left atrial thrombus identified.

Footnotes

  1. By definition, an insufficient valve is going to result in regurgitation of blood that falls back through the insufficient valve. It should be noted that a narrowed valve can also produce regurgitation. Insufficiency and regurgitation are used synonymously.
  2. Source: National Heart, Lung, and Blood Institute.
  3. This valve does tend to become infected in intravenous drug users, however.
  4. Inward movement of the inner surface of the heart wall.
  5. Increased thickness of the heart wall during contraction (systole) of the heart muscle.
  6. The coronary arteries are the arteries that provide blood the heart muscle itself, in contrast to the blood that the heart pumps. The major coronary arteries are the left main (LM), the left anterior descending (LAD), the circumflex (CX), and the right coronary artery (RCA). Echocardiograms do not provide generally provide visualization of coronary artery blockages, but easily show abnormal motions of the heart muscle when it receives inadequate blood flow secondary to the obstructing lesions characteristic of coronary artery disease.
  7. Congestive means the heart is unable pump forcefully enough with the result that there is abnormal fluid accumulation in tissues (edema), e.g., pulmonary edema, enlargement of the liver, and swelling in the feet and legs.
  8. Pulmonary edema can be seen on chest x-rays.
  9. A foramen ovale is a hole in the atrial septum or wall that separates the left and right atrial chambers of the heart. It is normally present in fetal life, but closes shortly after birth. If a foramen ovale persists after birth, it is called a patent foramen ovale (PFO). An isolated PFO in a child or adult is generally not considered an atrial septal defect (ASD), because it does not affect cardiac function. However, it can serve a role permitting blood clots to embolize to the brain and cause a stroke.
    Using contrast material in addition to the usual two-dimensional TEE can permit detection of PFO with a sensitivity of 89%, specificity and positive predictive values of 100%, and negative predictive value of 96%. These figures are based on the fact that with contrast TEE, even one microbubble in the blood seen abnormally crossing the atrial septum from the right to left atrium is diagnostic of an PFO. Using color Doppler TEE, sensitivity, specificity, positive predictive value, and negative predictive value of 100% have been reported for detecting PFO if a bidirectional shunt (left to right and right to left blood flow through the PFO) is used as the diagnostic criterion. Such shunting through the PFO is identified as a red jet on the color Doppler.
  10. The aorta arises upward from the left ventricle (ascending aorta), curves (aortic arch) and descends through the chest into the abdomen (descending aorta).
  11. Atrial septal aneurysm is a structural abnormality of the atrial septum, possibly resulting from a connective tissue defect, in which a weak area of septum separating the right and left atrial chambers of the heart bulges outward into the right atrium during cardiac systole (contraction) and into the left atrium during diastole (relaxation). A bulge of over 10 mm is most often associated with strokes, thought to be the result of blood clots forming in the area of the aneurysm. TEE is very useful in detecting atrial septal aneurysms, while standard transthoracic echocardiography will miss nearly half of such aneurysms over 10 mm. About 8% of the general population have atrial septal aneurysms, but about 39% of patients with stroke and no other determinable cause actually have such aneurysms.
  12. Also known as cross-sectional echocardiography and sector echocardiography, or simply as a 2-D echo.
  13. An allograft (allogeneic graft) is one between different individuals of the same species.
  14. Also known as “tissue Doppler imaging (TDI).”
  15. The patient had peripheral edema and there was a question of whether he might have heart failure.
  16. Calcification in the aorta or other heart structures such as valves is abnormal.
  17. A cusp is a valve leaflet. The movement of the cusps forms the opening or closure of the valve.
  18. The interventricular septum is the wall separating the right and left ventricles.
  19. Mitral valve prolapse (MVP) is a common and usually benign disorder most frequent in women. It consists of a form of degeneration of the mitral valve leaflets that makes them unusually floppy so that they do not hold their proper position. Patients with MVP are often asymptomatic. There may be chest pain that is rarely incapacitating, and unusual cases are associated with dangerous ventricular arrhythmias.
  20. The annulus is a thick fibrous ring that surrounds and helps fix each heart valve in position.
  21. The Doppler echocardiogram that was added to the basic M-Mode and sector echocardiographic study shows increased velocity of blood across the mitral valve. This finding permitted the calculation that there is a mildly increased gradient or pressure difference of 12 – 15 mm Hg across the mitral valve that suggests the valve is mildly stenosed.
  22. Although the mitral valve is stenosed, it does not provide good closure and a little blood falls back through-regurgitates.
  23. There is reduced motion of the aorta during cardiac contraction. This would be compatible with decreased ejection of blood through the aortic valve into the aorta, which like all arteries has some elasticity.
  24. Angle theta is a technical echocardiographic measurement.
  25. A frequently used subjective scale for increasing severity of valvular regurgitation is 0 – 4+.
  26. Trans-gastric means some echocardiographic views were taken after advancing the transducer into the patient’s stomach.
  27. It is normal for the aortic valve to be “triscupid”, i.e., have 3 cusps or leaflets. This should not be confused with the tricuspid valve that connects the right atrium and right ventricle of the heart.
  28. Sclerosis means “hardening” as could be deduced from lack of flexible movement.
  29. The aortic root is where the aorta arises from the left ventricle of the heart.
  30. “Sarcoidal” is in reference to a disease called sarcoidosis that can affect the heart.
  31. The patient had a blood clot in one of the arteries supplying the large intestine. One possible origin of such a thrombus is the heart, especially the left atrium of the heart. If so, it would be important to identify the cause in the heart before it pumps another blood clot to some other location such as the brain.
  32. The foramen ovale should be closed, so this is a normal finding.