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Patient with hypertension and systolic and diastolic murmurs at physical examination.
SSFP cine images were obtained in the three-chamber view (Movie 1) and subsequently through the plane of the aortic valve (Movie 2).
Movie 1. The three-chamber view reveals both stenotic and regurgitant jets, consistent with aortic stenosis and insufficiency.
Movie 2. The valve plane view shows a tricuspid valve with a stenotic orifice. Note that aortic regurgitation is not well seen on the transvalvular view.
Qualitatively, both regurgitation and insufficiency appear at least moderate. Quantitative evaluation was also performed by performing phase-contrast measurements in the proximal aorta both perpendicular to the aorta and to the stenotic flow jet (Fig 15).
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Figure 15. (a) Time-velocity curve obtained from a cine phase-contrast sequence oriented perpendicular to the stenotic flow jet. This demonstrates a peak systolic velocity of 4.05 m/sec, corresponding to a peak pressure gradient of 65 mm Hg. This is consistent with moderate aortic stenosis. (b) Flow curve obtained through the proximal aorta and demonstrates substantial reversal of flow during diastole. The regurgitant volume was 50 mL, and the regurgitant fraction was 40%, consistent with moderately severe regurgitation.
LV function was also evaluated (Movie 3).
Movie 3. Short-axis cine images reveal normal function and ejection fraction but mild LV hypertrophy.
Patient with abnormal chest radiograph and heart murmur.
Movie 4. Axial (left) and coronal black-blood double-inversion-recovery sequences reveal apparent LV hypertrophy (confirmed on short-axis cine images) and dilatation of the ascending aorta, which was responsible for the radiographic abnormality. Dilatation of the aorta is associated with aortic stenosis but could also be a cause of aortic insufficiency, although the aortic root is only mildly dilated. LV hypertrophy is more common in aortic stenosis.
Movie 5. SSFP three-chamber views obtained in slightly different orientations show combined aortic stenosis and insufficiency. Note that the stenotic jet is eccentrically oriented, as is often the case, so that phase-contrast sections used to measure peak velocity will have to be oriented differently from those used to determine the regurgitant volume (Fig 16). Note also the swirling flow in the aorta during diastole, likely a result of the eccentric stenotic jet. This will complicate measurements of aortic regurgitation.
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Figure 16. (a) Section is positioned at the level of the coronary ostia perpendicular to the valve plane and the regurgitant jet; this section is used for measurement of regurgitant volume. (b) Another section is oriented perpendicular to the course of the eccentrically oriented systolic jet and is used to measure peak systolic velocity.
Movie 6. Valve plane cine images reveal a bicuspid aortic valve. Signal void is noted in the region of the valve on these and the previous cine images (Movie 5). This likely represents calcification, which was also noted at echocardiography.
Patient with history of mitral valve prolapse. Transthoracic echocardiography was limited owing to a poor acoustic window. Previous examinations had noted mild mitral insufficiency. The most recent echocardiogram suggested severe mitral regurgitation.
Movie 7. Vertical (left) and oblique long-axis cine images reveal mitral regurgitation. Note that the regurgitant jet is much more prominent on the oblique view than the vertical long-axis view. This emphasizes the importance of obtaining cine images in multiple orientations when evaluating valvular stenosis or insufficiency; jets are often eccentric, and the severity of a lesion could easily be underestimated by imaging in a suboptimal orientation. Note also minimal thickening of the posterior leaflet of the valve.
There are several ways to quantify the regurgitant volume. One approach (perhaps the easiest) is to obtain cine phase-contrast images through the proximal aorta and main pulmonary artery.
Movie 8. If no other valvular lesion is present, the difference between flow through the main pulmonary artery (right) and flow through the aorta (left) is equivalent to the regurgitant volume.
Movie 9. Similarly, short- (shown here) or long-axis cine images through the ventricles could be obtained and stroke volumes measured. Again, the difference in stroke volumes should represent the regurgitant volume, assuming isolated mitral insufficiency.
A third possibility is to combine the first two methods: measure forward flow through the aorta with a phase-contrast sequence and LV stroke volume from short-axis cine images. The difference should represent the regurgitant volume. This method avoids the problem of tracing right ventricular volumes on short-axis images, which is not always straightforward.
A fourth possibility is to evaluate regurgitation directly by placing a cine phase-contrast section at or adjacent to the mitral valve plane and then measuring regurgitant flow. The difficulty with this method is tracing the area of the regurgitant jet with sufficient precision to obtain an accurate measurement of flow.
Quantitative measurements with these four methods were in reasonable agreement and yielded a regurgitant volume of 15–25 mL, consistent with mild mitral insufficiency.
Patient with remote history of rheumatic fever. Recent onset of dyspnea on exertion.
Movie 10. Four-chamber long-axis cine images show dilatation of the left atrium and an eccentric jet due to mitral stenosis. There is also thinning of the LV apex. In addition, the patient had aortic insufficieny. The combination of these two lesions strongly suggests rheumatic disease as the cause.
Patient with history of a valvular lesion since birth, with increasing shortness of breath and fatigue.
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Figure 17. Two views from a sagittal gradient-echo scout sequence show marked dilatation of the main pulmonary artery. This is suggestive of pulmonic stenosis.
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| Movie 11. | Movie 12. | Movie 13. |
Movies 11–13. Axial oblique (Movie 11), sagittal oblique (Movie 12), and coronal oblique (Movie 13) SSFP images through the pulmonic valve clearly show a stenotic jet in the proximal pulmonary artery. What is not so evident on these less than ideal images is a substantial amount of pulmonic regurgitation. The results of quantitative flow measurements with these cine images are in Figure 18.
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Figure 18. (a) Flow curve shows a regurgitant volume of 45 mL. (b) Time-velocity curve through the stenotic jet shows a peak systolic velocity of 2.45 m/sec, corresponding to a peak gradient of 24 mm Hg. These results are consistent with moderate pulmonic stenosis and insufficiency. Clinically, pulmonic insufficiency was more significant, and a prosthetic valve was placed shortly after the MR examination.
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