Cardiomyopathies, Hypertensive, and Pulmonary Heart Disease

Cardiomyopathies

General Step-By-Step Approach

An overall approach to patients with a known or suspected cardiomyopathy is reviewed, followed by specific features of each type of cardiomyopathy.

Step 1: Measure Left Ventricular Chamber Size and Systolic Function

Left Ventricular Chamber Size

▪ Two-dimensional (2D) guided M-mode measurement of left ventricle (LV) minor axis internal dimensions at end-diastole and end-systole.
▪ Three-dimensional (3D) volumetric or apical biplane calculation of end-diastolic and end-systolic ventricular volumes (Figs. 9.1 and 9.2).

Key Points

□ 3D volumetric LV volumes indexed to body size are the most accurate approach for evaluation of LV dilation because the pattern of dilation may not be reflected in basal minor axis dimensions.
□ 2D LV internal dimensions are measured from the parasternal window, because the ultrasound beam is perpendicular to the blood-myocardial interface, providing high axial resolution.
□ 2D imaging in long-and short-axis views will ensure that the dimension is measured in the minor axis of the ventricle (not at an oblique angle, which would overestimate size).
□ On 2D images, the white–black (tissue–blood) interface is used to measure LV dimensions.
□ The rapid sampling rate of M-mode (compared with the slow frame rate of 2D imaging) provides more accurate identification of the endocardial borders (Fig. 9.3).
□ 2D guided M-mode measurements are most accurate when the ultrasound beam can be aligned perpendicular to the LV wall of interest.
□ For sequential studies, measurements should be made with the same method at the same location.

Left Ventricular Systolic Function

▪ LV ejection fraction is calculated using 3D volumes or the 2D apical biplane approach.
▪ Global longitudinal strain is measured using speckle tracking imaging.
▪ LV dP/dt is calculated from the mitral regurgitation velocity curve (Fig. 9.4).
▪ Forward stroke volume is measured in the LV outflow tract and indexed to body size.
▪ Regional ventricular function is evaluated qualitatively as normal, hypokinetic, or akinetic for each myocardial segment (see Chapter 8).

Key Points

□ Ejection fraction measured by the apical biplane method is confirmed by a visual estimate to ensure image quality is adequate for quantitation.
□ The traced endocardial borders are reviewed for accuracy and retraced if the estimated and measured ejection fractions differ by more than 10 ejection fraction units.
□ Echo-contrast is used to enhance identification of endocardial borders when image quality is suboptimal.
□ Measured ejection fraction is reported whenever possible. The estimated ejection fraction is reported only if endocardial borders cannot be traced accurately or a 3D measurement is not possible.
Fig. 9.3 M-mode tracing of the LV.The 2D image is used to ensure the M-line is perpendicular to the long axis of the LV in the parasternal long-axis view and in the middle of the chamber in the short-axis view. The rapid sampling rate of the M-mode recording (time on the horizontal axis) provides more accurate identification and measurement of septal and posterior wall thickness and ventricular chamber dimensions at end-diastole (onset of QRS) and end-systole (maximum posterior motion of septum). Ao, Aorta.
Fig. 9.4 Rate of LV pressure increase.The rate of increase in velocity of the mitral regurgitant jet is markedly reduced in early systole. The calculated dP/dt of 427 mm Hg/s indicated severely reduced LV contractility.
□ Ejection fraction is an imperfect measure of contractility because it is affected by loading conditions. Even so, ejection fraction is useful for clinical decision making.
□ LV dP/dt and forward stroke volume are other useful parameters of LV systolic function (see Chapter 6).
□ Indirect qualitative indicators of LV systolic dysfunction include M-mode findings of reduced aortic root motion and increased E-point septal separation (Fig. 9.5).
□ Global longitudinal strain is more independent of loading conditions and more sensitive for detection of early LV systolic dysfunction.

Evaluate for Other Cause of Left Ventricular Dilation and Systolic Dysfunction

▪ A cardiomyopathy is defined as a primary disease of the myocardium in the absence of coronary or valvular disease.
▪ Evaluate for evidence of other causes of LV dilation and dysfunction, specifically valve disease (aortic stenosis, mitral regurgitation, or aortic regurgitation) and coronary artery disease.

Key Points

□ LV dilation and dysfunction due to coronary disease with myocardial infarction or hibernation can be difficult to distinguish from a primary cardiomyopathy.
□ Mitral regurgitation may be a cause or a consequence of LV dilation and dysfunction. When more than mild mitral regurgitation (vena contracta >3 mm) is present, careful quantitative evaluation is helpful (see Chapter 12) (Fig. 9.6).
□ The degree of aortic valve leaflet opening is reduced when LV dysfunction is present, making it difficult to separate severe aortic stenosis resulting in LV dysfunction from moderate aortic stenosis with coincidental LV dysfunction (see Chapter 11) (Fig. 9.7).

Step 2: Evaluate for the Presence and Pattern of Ventricular Hypertrophy

Presence and Severity of Left Ventricular Hypertrophy

▪ 2D guided M-mode measurement of LV wall thickness
▪ Calculation of LV mass in selected cases

Key Points

□ 2D guided M-mode measurement of LV wall thickness at end-systole (onset of the QRS) is adequate in most cases.
□ Calculation of LV mass from traced 2D endocardial and epicardial borders is largely limited to research applications.

Pattern of Left Ventricular Hypertrophy

▪ Long-axis, short-axis, and apical views are used to evaluate the pattern of ventricular hypertrophy (Fig. 9.8).

Key Points

□ 2D imaging allows evaluation of the pattern of hypertrophy in all myocardial segments.
□ When hypertrophy is concentric, LV wall thickness measurements at one site adequately represent the degree of hypertrophy.
□ When hypertrophy is asymmetric, measurements at key sites are reported, particularly the diastolic septal thickness in patients with hypertrophic cardiomyopathy.
□ 2D guided M-mode measurements are most accurate when the ultrasound beam can be aligned perpendicular to the LV wall of interest. Otherwise, 2D measurements at end-diastole are reported.

Step 3: Assess Left Ventricular Diastolic Function (see Chapter 7)

▪ LV and LA inflow patterns (Fig. 9.9)
▪ Tissue Doppler at the mitral annulus (Fig. 9.10)
▪ Isovolumic relaxation time (Fig. 9.11)

Key Points

□ Systolic LV dysfunction typically is accompanied by some degree of diastolic dysfunction.
□ Classification of the degree of diastolic dysfunction as mild (impaired relaxation) versus severe (decreased compliance) is used in clinical decision making.
□ LV filling pressures are estimated whenever systolic dysfunction is present.

Step 4: Estimate Pulmonary Artery Pressures (see Chapter 6)

▪ Pulmonary systolic pressure is estimated from the tricuspid regurgitant (TR) jet velocity and estimated right ventricular (RA) pressure (Figs. 9.12 and 9.13).
▪ Other signs of pulmonary hypertension include a short time to peak velocity in the pulmonary artery velocity curve, paradoxical septal motion, and a high end-diastolic pulmonic regurgitant velocity.

Key Points

□ Pulmonary pressures often are elevated in patients with heart failure due to a cardiomyopathy.
□ Pulmonary pressures may be reduced with effective medical therapy, in conjunction with a decrease in left atrium (LA) (or LV filling) pressure.
□ When pulmonary pressures are elevated disproportionately to the degree of left-sided heart dysfunction, concurrent primary pulmonary disease or pulmonary thromboembolism may be present.

Step 5: Evaluate Right Ventricular Size and Systolic Function

▪ RV size and systolic function are assessed from parasternal, apical, and subcostal views (Fig. 9.14).
▪ Standard measures of RV size and function are used (see Chapter 6).

Key Points

□ RV systolic dysfunction may be due to primary myocardial disease affecting both ventricles or to the effects of pulmonary hypertension.
□ Qualitative assessment of RV size and function takes into account the degree of LV dilation and dysfunction. RV lengthwise systolic shortening and tricuspid annular plane systolic excursion (TAPSE) are reduced when RV dysfunction is present.

Step 6: Evaluate the Severity of Mitral and Tricuspid Regurgitation (see Chapter 12)

▪ Mitral and tricuspid regurgitation often are present in patients with a cardiomyopathy.
Fig. 9.12 Estimates of pulmonary systolic pressure.This tricuspid regurgitant (TR) jet velocity obtained from an apical view (APX TV) has a peak somewhere around 2.5 m/s. This signal is not ideal because the peak is not well defined. This likely is due to the position of the ultrasound beam relative to the jet and the use of color coding (instead of gray scale) for the spectral display, which often obscures the peak velocity with superimposed noise. However, the peak velocity of about 2.4 m/s indicates a RV-to-RA systolic pressure difference of 23 mm Hg.
Fig. 9.13 RA pressure.The junction of the inferior vena cava (IVC) and RA is visualized from the subcostal window for estimating RA pressure. In this patient, the IVC diameter is about 2.5 cm and collapses less than 50% with rapid inspiration (SNIFF), which is consistent with an RA pressure of 10 to 15 mm Hg.
▪ Regurgitant severity is evaluated using standard approaches, starting with the color Doppler vena contracta and the continuous-wave (CW) Doppler velocity curve.
▪ The mechanism of regurgitation is evaluated using 2D imaging from multiple views; typically regurgitation is secondary to ventricular dilation and dysfunction, but some patients have concurrent structural valve disease.

Key Points

□ Mitral and tricuspid regurgitation due to LV dilation and dysfunction are common.
□ The mechanism of atrioventricular valve regurgitation is tethering of the mitral leaflets resulting in incomplete systolic coaptation. This also has been described as an increased angle between the papillary muscles so that the leaflets are “pulled apart” relative to the mitral annulus (Fig. 9.15).
□ The degree of annular dilation is variable, with a variable contribution to the degree of mitral regurgitation.
□ Mitral regurgitation severity may decrease with effective therapy for heart failure.

Step 7: Evaluate Left Atrium Size (see Chapter 2)

▪ LA size typically is increased either due to chronic elevation of LV filling pressures or to coexisting mitral regurgitation (see Fig. 2.22).
▪ LA size can be evaluated qualitatively, using a simple anterior-posterior dimension, or by calculation of atrial volume from apical views.

Key Points

□ LA anterior-posterior dimension is measured in a long-axis view at end-systole (maximum LA dimension).
□ Although atrial volumes are predictive of clinical outcome, simpler measures of atrial size suffice for clinical decision making in many cases.
□ When clinically indicated, LA volume is calculated from tracing the LA border at end-systole in apical 4-chamber and 2-chamber views. LA volume then is indexed for body size.
□ RA size also may be increased and is evaluated qualitatively (as mild, moderately, or severely dilated) in comparison to the other cardiac chambers.

Additional Steps

Dilated Cardiomyopathy

▪ Evaluate for LV apical thrombus (Fig. 9.16).
▪ Differentiate from end-stage coronary disease (Table 9.1).
Fig. 9.16 LV apical thrombus.(A) In the apical 4-chamber view, the LV is dilated with marked thickening along the apical septum suggestive of thrombus. (B) Using a higher transducer frequency and shallow image depth, the laminated thrombus filling the apex is better visualized. At this depth, a ring-down artifact also is seen overlying the LV chamber.

TABLE 9.1

Cardiomyopathies: Clinical Echocardiographic Correlation
Cardiomyopathy	Pathophysiology	Clinical Presentation	Echocardiographic Findings
Dilated
Idiopathic	Primary myocardial dysfunction of unknown cause	• Heart failure signs and symptoms	• Dilation of all four chambers with RV and LV systolic dysfunction • Secondary mitral regurgitation in some patients, but valve leaflets are normal • LV thrombus can occur with severe LV dysfunction • Elevated LV filling pressures with variable elevation in PA pressures
Familial	Inherited primary myocardial dysfunction	• Heart failure signs and symptoms	• Dilation of all four chambers with RV and LV systolic dysfunction • Secondary mitral regurgitation may be present, but valve leaflets are normal • LV thrombus can occur with severe LV dysfunction • Elevated LV filling pressures with variable elevation in PA pressures
Chagas	Protozoan infection, due to Trypanosoma cruzi, that affects the heart, esophagus, and colon	• Acute phase is characterized by fever, myalgias, hepatosplenomegaly, and myocarditis. • Chronic Chagas heart disease has a high mortality rate (44% at 4 years) due to sudden death (55%-65%), heart failure (25%-30%), and stroke (10%-15%)	• LV dilation and systolic dysfunction, ranging from mild to severe • Wall motion may be regional but not in a pattern consistent with coronary artery disease • Apical abnormalities are common: with apical aneurysm in about 5% of asymptomatic patients and about 55% of those with heart failure
Duchenne MD	Inherited myopathic disorder that affects both skeletal and cardiac muscle	• Often have asymptomatic LV dysfunction, likely due to limited physical activity • Late in disease, heart failure and arrhythmias are seen	• Echocardiography is consistent with a dilated cardiomyopathy
Table Continued

Hypertrophic
Hypertrophic	Inherited autosomal-dominant myocardial disease	• Wide age range of clinical presentation • Often diagnosed in asymptomatic patients on screening echo • Present with symptoms of heart failure and angina or as sudden death with no previous diagnosis	• Asymmetric LV hypertrophy with normal systolic function but abnormal diastolic function • About ⅓ have resting dynamic outflow obstruction, and ⅓ have a provoked gradient with exercise
Fabry	Inherited X-linked glycolipid storage disease, now recognized in women as well as men	• Presents in boys under age 10 years with skin and neurologic findings • Presents in women later in life with unexplained LV hypertrophy • Diagnosis based on plasma alpha-galactosidase A activity • Conduction system abnormalities and arrhythmias are common	• LV hypertrophy may be asymmetric but in an atypical pattern for HCM • Endocardial hyperechoic layer is typical for Fabry heart disease • About 50% have aortic and mitral valve thickening and mild regurgitation
Restrictive
Amyloid	Extracellular tissue deposition of serum protein subunit fibrils—cardiac involvement in 50% of primary AL amyloidosis (monoclonal light chains) cases but only 5% with secondary AA amyloidosis	• Conduction system disease • Myocardial involvement	• Increased LV and RV wall thickness with increased myocardial echogenicity, but “sparkling” appearance is not specific or sensitive for diagnosis • Progressive diastolic dysfunction • Valve thickening • Intracardiac thrombus • Strain pattern with preserved apical function
Sarcoidosis	Systemic disease with pulmonary involvement in most patients Subclinical cardiac involvement in up to 20% of patients	• Cardiac involvement most often results in conduction system abnormalities, ventricular arrhythmias or heart failure Only gold members can continue reading. Log In or Register to continue Share this: Click to share on Twitter (Opens in new window) Click to share on Facebook (Opens in new window) Related Related posts: Specialized Echocardiography Applications Intraoperative and Interventional Echocardiography Endocarditis Valvular Regurgitation Stay updated, free articles. Join our Telegram channel Tags: Echocardiography Review Guide Apr 23, 2020 \| Posted by admin in CARDIOLOGY \| Comments Off on Cardiomyopathies, Hypertensive, and Pulmonary Heart Disease Full access? Get Clinical Tree Get Clinical Tree app for offline access Get Clinical Tree app for offline access

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Cardiomyopathies, Hypertensive, and Pulmonary Heart Disease

Cardiomyopathies, Hypertensive, and Pulmonary Heart Disease

Cardiomyopathies

General Step-By-Step Approach

Step 1: Measure Left Ventricular Chamber Size and Systolic Function

Left Ventricular Chamber Size

Key Points

Left Ventricular Systolic Function

Key Points

Evaluate for Other Cause of Left Ventricular Dilation and Systolic Dysfunction

Key Points

Step 2: Evaluate for the Presence and Pattern of Ventricular Hypertrophy

Presence and Severity of Left Ventricular Hypertrophy

Key Points

Pattern of Left Ventricular Hypertrophy

Key Points

Step 3: Assess Left Ventricular Diastolic Function (see Chapter 7)

Key Points

Step 4: Estimate Pulmonary Artery Pressures (see Chapter 6)

Key Points

Step 5: Evaluate Right Ventricular Size and Systolic Function

Step 6: Evaluate the Severity of Mitral and Tricuspid Regurgitation (see Chapter 12)

Key Points

Step 7: Evaluate Left Atrium Size (see Chapter 2)

Key Points

Additional Steps

Dilated Cardiomyopathy

Thoracic Key

Fastest Thoracic Insight Engine

Cardiomyopathies, Hypertensive, and Pulmonary Heart Disease

Cardiomyopathies

General Step-By-Step Approach

Step 1: Measure Left Ventricular Chamber Size and Systolic Function

Left Ventricular Chamber Size

Key Points

Left Ventricular Systolic Function

Key Points

Evaluate for Other Cause of Left Ventricular Dilation and Systolic Dysfunction

Key Points

Step 2: Evaluate for the Presence and Pattern of Ventricular Hypertrophy

Presence and Severity of Left Ventricular Hypertrophy

Key Points

Pattern of Left Ventricular Hypertrophy

Key Points

Step 3: Assess Left Ventricular Diastolic Function (see Chapter 7)

Key Points

Step 4: Estimate Pulmonary Artery Pressures (see Chapter 6)

Key Points

Step 5: Evaluate Right Ventricular Size and Systolic Function

Key Points

Step 6: Evaluate the Severity of Mitral and Tricuspid Regurgitation (see Chapter 12)

Key Points

Step 7: Evaluate Left Atrium Size (see Chapter 2)

Key Points

Additional Steps

Dilated Cardiomyopathy

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