Valvular Heart Disease
Valvular heart disease is an important consideration in patients with different clinical presentations such as shortness of breath, chest pain, syncope, and hypotension . Correct identification of valvular heart disease requires good knowledge of anatomy, pathophysiology and advanced ultrasound applications(such as color and spectral Doppler), as well as excellent ultrasound examination skills. In most cases, precise quantification of the valvular pathology requires comprehensive echocardiography using a high-end ultrasound platform . Point-of-care ultrasound may assist in identification of common valvular diseases, but caution should be exercised in interpreting the abnormalities by less experienced examiners, especially ruling out significant valvular heart disease based on limited ultrasound examination (Figs. 20.1, 20.2, 20.3, 20.4, 20.5, 20.6, 20.7, 20.8, 20.9, 20.10, and 20.11; Videos 20.1, 20.2, 20.3, 20.4, 20.5, 20.6, 20.7, 20.8 and 20.9) .
KeywordsPoint-of-care cardiac ultrasound Valvular disease Mitral valve Aortic valve Tricuspid valve Stenosis Endocarditis
All videos courtesy of Dr. Edgar Argulian.
Mitral stenosis, apical four-chamber view. In this view, the left atrium (LA), right atrium (RA), left ventricle (LV), and right ventricle (RV) are seen. The left atrium is markedly enlarged. The mitral valve (MV) appears echo dense and thickened, the posterior leaflet is immobile and anterior leaflet has restricted mobility. This is consistent with rheumatic mitral valve stenosis. See also Fig. 20.2 (AVI 5658 kb)
Mitral stenosis, color Doppler examination in the apical four-chamber view. Color Doppler examination in this view shows color flow convergence (arrow) in the left atrium (LA) which indicates blood flow acceleration toward the narrowed orifice of the mitral valve in diastole. See also Fig. 20.3 (AVI 4930 kb)
Infective endocarditis involving the mitral valve in a patient with shortness of breath and fever. Color Doppler echocardiography can identify mitral regurgitation and can help in gross estimation of the lesion severity. Careful attention must be paid to color Doppler settings such as Nyquist limit and color Doppler gain. In this patient, color Doppler demonstrates a jet of severe mitral regurgitation (arrows) with a large area of flow convergence (F). Quantitative assessment of the mitral regurgitation severity by the size of the regurgitant jet can be misleading and can result in both under- and overestimating lesion severity. Eccentric mitral regurgitation jets can have small jet areas and can be missed by the limited assessment using point-of-care ultrasound. Therefore, comprehensive echocardiography is required for accurate mitral regurgitation assessment and quantification. See also Fig. 20.6 (AVI 3223 kb)
Aortic stenosis in the parasternal long-axis view. An attempt to visualize the aortic valve opening should be made in the parasternal views. In this parasternal long axis view the left ventricle (LV), left atrium (LA), mitral and aortic valves, and the aortic root (Ao) are seen. The mitral valve (MV) appears echo bright but opens normally. The aortic valve (AV) appears echo bright with very restricted leaflet opening suggestive of aortic stenosis. See also Fig. 20.7 (AVI 21797 kb)
Five-chamber view for evaluation of aortic stenosis. Doppler interrogation of the transaortic velocities is essential in diagnosing aortic stenosis and other causes of left ventricular outflow obstruction. This can be achieved by obtaining a five-chamber view: from the usual four-chamber view the transducer is tilted anteriorly (shallower relative to the chest) to visualize the left ventricular outflow tract (LVOT), aortic valve (AV) and the ascending aorta (Ao). Continuous wave (CW) spectral Doppler can be aligned parallel to the left ventricular outflow using this view to capture the transaortic velocity. While this interrogation can assist in diagnosing aortic stenosis, proper aortic stenosis grading requires multiple interrogations from different insonation angles and should be performed during comprehensive echocardiography. See also Fig. 20.8 (AVI 4001 kb)
Structural assessment of the tricuspid valve using point of care ultrasound. Tricuspid valve assessment can be accomplished in different views including parasternal, apical and subcostal views. The apical four-chamber view is commonly used for point-of-care ultrasound. Tricuspid regurgitation is a relatively common finding. Most commonly, moderate-to-severe tricuspid regurgitation is secondary to right ventricular dilation. In this example, the right ventricle (RV) and right atrium (RA) are enlarged. A coaptation gap can be seen between the tricuspid valve leaflets in systole due to tricuspid annular dilation. See also Fig. 20.10 (AVI 11834 kb)
Tricuspid valve assessment using color Doppler. Color Doppler allows gross assessment of the tricuspid regurgitation severity but examination limited to a single view can be misleading. Careful attention must be paid to color Doppler settings such as Nyquist limit and color Doppler gain. In this example, color Doppler examination demonstrates a large jet of tricuspid regurgitation (arrow) consistent with significant tricuspid regurgitation. Spectral Doppler assessment of the tricuspid regurgitant jet can also be performed in this view. Although it can be used to estimate pulmonary artery systolic pressure, interrogation from multiple angles is required for complete assessment which is typically accomplished by comprehensive echocardiography. See also Fig. 20.11 (AVI 4308 kb)