1. Correct Answer: D. The specific type of MR the patient has may be caused by prior inferior wall MI.

Rationale: This patient has significantly decreased systolic LV function. He also had significant (moderate-severe) MR, despite the CD signature being less than impressive. CHF exacerbation as well as worsening MR (caused by progressively more dilated left ventricle and increasing LV pressures) have likely contributed to his presentation. The MR jet in this case is posteriorly directed. With a structurally normal MV, a posteriorly directed MR jet can be a result of either prolapse of the anterior leaflet or apical tethering of the posterior leaflet. The latter is commonly a sequela of inferior wall infarction. Both leaflets in this case are tethered, but the posterior one more than the anterior one.

Increase in LA size is generally a reflection of chronically elevated LA pressures. However, chronic atrial fibrillation destroys that relationship: significant LA dilation is frequently seen in the absence of elevated LA pressures.

The most basic method of semiquantitatively grading the severity of MR is based on the area of the regurgitant jet relative to the area of the left atrium. Generally, jets occupying >40% of the atrium indicate severe MR, and those which occupy <10% indicate mild, insignificant MR. Eccentric MR jets, however, constitute a special case. When the turbulent jet of MR comes in contact with the atrial wall, kinetic energy is dissipated and CD signal decreases, resulting in visual underestimation of the jet severity (Coanda effect). In general, eccentricity of the jet should upstage its severity, as judged by area of the jet body. Severe dilation of the left atrium may make the jet area appear relatively smaller and thus less significant.

MV leaflets indeed seem not to open all the way in diastole. However, they appear relatively structurally normal. This is not a finding of MS, but rather is most commonly due to dysfunction of the left ventricle. Proximity of the anterior mitral leaflet to the septum during diastole may be used as an indirect index of systolic function. This measure, called EPSS, increases when LV systolic function is poor. In addition, aortic insufficiency (AI), which this patient also happened to have, appears to hit the anterior leaflet of the MV and prevent its full opening in diastole.

1. Zoghbi WA, Adams D, Bonow RO, et al. Recommendations for noninvasive evaluation of native valvular regurgitation: a report from the American Society of Echocardiography developed in collaboration with the Society for Cardiovascular Magnetic Resonance. J Am Soc Echocardiogr. 2017 Apr;30(4):303-371. doi:10.1016/j.echo.2017.01.007. Epub 2017 Mar 14.

2. Correct Answer: D. MV anatomy suggests that MR is likely secondary to dilated cardiomyopathy and not its cause.

Rationale: PLAx view clearly shows that in systole when the MV closes, MV leaflets do not reach the plane of the MV annulus (Figure 25.34). This is a result of MV leaflets being tethered by the subvalvular apparatus (PMs and chordae). Tethering of just (or predominantly) the posterior MV leaflet can be seen after an MI, especially after an inferolateral MI, but symmetric tethering is almost invariably secondary to chronic LV dilation and alteration in LV shape with apical and lateral displacement of the PMs. Consequently, MV fails to close in systole, resulting in secondary MR.

1. Dudzinski DM, Hung J. Echocardiographic assessment of ischemic mitral regurgitation. Cardiovasc Ultrasound. 2014 Nov 21;12:46. doi:10.1186/1476-7120-12-46.

3. Correct Answer: A. Figure 25.3A. VC is properly measured in the parasternal long-axis (PLAx) view.

Rationale: VC is properly measured in PLAx view, as shown in Figure 25.3A. In the PLAx view, the MR flow is (almost) perpendicular to the insonation beam, while in A4 it is (almost) parallel to it. Because lateral resolution of CD is poor, measurement of VC in A4 will often result in significant overestimation of the width of the jet.

VC width is an established measure of MR severity. It is defined as the narrowest part of the jet on CD and cannot be identified reliably in the transverse PSAx view.

This patient was confirmed to have moderate-severe MR by other echocardiographic measures.

1. Zoghbi WA, Adams D, Bonow RO, et al. Recommendations for noninvasive evaluation of native valvular regurgitation: a report from the American Society of Echocardiography developed in collaboration with the Society for Cardiovascular Magnetic Resonance. J Am Soc Echocardiogr. 2017 Apr;30(4):303-371. doi:10.1016/j.echo.2017.01.007. Epub 2017 Mar 14.

4. Correct Answer: B. Dilated cardiomyopathy.

Rationale: The appearance of a small MV relative to the size of the mitral annulus is typical of dilated cardiomyopathy and is also a frequent cause of MR, secondary to the failure of the leaflets to coapt in systole. (See Figure 25.35 and Video 25.49.)

The appearance of a restricted MV opening is secondary to the leaflets being tethered by the PMs, which are now further away from the MV in dilated cardimyopathy. The restriction is generally uniform without any part of the leaflet affected more than others. Also, a low stroke volume in a patient with dilated cardiomyopathy leads to reduced opening of the mitral leaflets during diastole (due to reduction in diastolic blood flow from the left atrium to the left ventricle). This appearance is commonly misinterpreted by beginner sonographers as MS, which it is not. Presence of rheumatic MV disease is virtually excluded by lack of sclerosis, calcifications, and fusions of the commissures. Endocarditis and AI cannot be excluded, but the appearance of the dilated MV annulus in the presence of decreased LV systolic function is highly characteristic of MV dysfunction secondary to dilated cardiomyopathy. This patient had diabetes with severely decreased LV systolic function. The procedure he had abroad was coronary catheterization.

1. Zoghbi WA, Adams D, Bonow RO, et al. Recommendations for noninvasive evaluation of native valvular regurgitation: a report from the American Society of Echocardiography developed in collaboration with the Society for Cardiovascular Magnetic Resonance. J Am Soc Echocardiogr. 2017 Apr;30(4):303-371. doi:10.1016/j.echo.2017.01.007. Epub 2017 Mar 14.

5. Correct Answer: B. B

Rationale: Regurgitant jet is said to have a conversion zone, located above the plane of the valve in the sending chamber (the left ventricle in this case) and a body of the jet, within the receiving chamber (in this case the left atrium). In between the two, just under the valve, the jet narrows. This part of the jet is called VC. VC width correlates with severity of regurgitation.

1. Zoghbi WA, Adams D, Bonow RO, et al. Recommendations for noninvasive evaluation of native valvular regurgitation: a report from the American Society of Echocardiography developed in collaboration with the Society for Cardiovascular Magnetic Resonance. J Am Soc Echocardiogr. 2017 Apr;30(4):303-371. doi:10.1016/j.echo.2017.01.007. Epub 2017 Mar 14.

6. Correct Answer: C. This is a significant MR that is likely contributing to the patient’s symptoms. Image in Figure 25.7C is the most representative of the degree of the MR and in other images CD is undergained.

Rationale: Changes in Doppler scale and gain significantly affect appearance of MR on CD imaging. The appropriate scale setting depends on prevalent velocities of blood flow. Recognize that:

The standard optimization of color gain is performed as follows:

The gain is not excessive in any of the three images shown and therefore the one with the highest gain will reflect the severity of the regurgitation best. The jet in Figure 25.7C occupies >40% of the left atrium and is therefore consistent with severe MR. It is possible that it is still underestimating the degree of MR, but there is no way to upstage MR already assigned the grade of “severe.” Therefore, Figure 25.7C is the most accurate. Remaining Figures 25.7A and 25.7B are undergained and underestimating the degree of MR.

Acute MR, listed in answer B, is a very important condition that may elude detection by both physical examination and echocardiography. Several typical features of acute MR are worth keeping in mind:

Note that this patient’s MR is symmetric in appearance, left atrium is dilated, LV systolic function is decreased, and both leaflets appear tethered. This is a typical appearance of MR secondary to dilated cardiomyopathy. The patient is hemodynamically stable and is not in any extremis. He is unlikely to have an acute MR.

1. Thomas JD. Doppler echocardiographic assessment of valvular regurgitation. Heart. 2002 Dec;88(6):651-657. doi:10.1136/heart.88.6.651.

7. Correct Answer: D. EPSS or E-point septal separation

Rationale: In M-mode displacement is plotted on the Y-axis and time on the X-axis. In Figure 25.36 the blue line represents the movement of the anterior leaflet and the red line the posterior leaflet over time. The distance between the two increases in diastole when the valve is open and decreases in systole when the valve is closed. The MV opens twice during each cardiac cycle: once during rapid ventricular filling and once during atrial contraction, designated as E and A, respectively. The measured minimal separation between the anterior leaflet of the MV and the septum, which occurs in diastole, specifically during the E-event, is called EPSS. It is an indirect surrogate of the LV systolic function. Values of >7 mm are highly predictive of severely reduced LV systolic function. Note that EPSS is an indirect measure of LV systolic function, a correlate, because the event occurring in diastole may not in principle be a direct reflection of ejection, occurring in systole. As seen in the case images, this patient indeed has severely impaired LV systolic function.

TAPSE is an apicobasal displacement of the tricuspid valve (TV) annulus during systole and is a measure of RV systolic function. S’ is the velocity of that (systolic) displacement as captured by tissue Doppler imaging (TDI) and is too a measure of RV contractility. SAM is an abnormal systolic movement of the anterior leaflet of the MV, which would be detected by the same M-mode tracing. Pressure half-time is a measure of rapidity of mitral inflow used for assessment of MS severity and is a spectral Doppler measure.

1. McKaigney CJ, Krantz MJ, La Rocque CL, Hurst ND, Buchanan MS, Kendall JL. E-point septal separation: a bedside tool for emergency physician assessment of left ventricular ejection fraction. Am J Emerg Med. 2014 Jun;32(6):493-497. doi:10.1016/j.ajem.2014.01.045. Epub 2014 Feb 3.

8. Correct Answer: C. All of the above are correct statements.

Rationale: The MV has a complex geometric shape, and though in primary MR the regurgitant orifice is roughly circular, it has a more complex shape in secondary MR, which occurs along the coaptation line of the two mitral leaflets. (See Figure 25.37.)

Consequently, particularly in secondary MR, depending on the tomographic scan plane, the jet of MR may have a different appearance. This is especially striking in the case of the apical two-chamber view, in which the scan plane is parallel to a large segment of the coaptation line between the two leaflets. (See Figure 25.38.)

In functional MR with its slit-like or oval regurgitant orifice, the jet area will be larger in apical two-chamber view than in apical four-chamber view. (See Figure 25.39.)

In primary MR, with a round regurgitant orifice, in the apical two-chamber view the jet may be missed entirely.

1. Fields A. Mitral valve: echo perspective. Cardioserv. Accessed April 23, 2021. https://www.cardioserv.net/echo-mitral-valve/.

2. Lancellotti P, Tribouilloy C, Hagendorff A, et al. Recommendations for the echocardiographic assessment of native valvular regurgitation: an executive summary from the European Association of Cardiovascular Imaging. Eur Heart J Cardiovasc Imaging. 2013 Jul;14(7):611-644. doi:10.1093/ehjci/jet105. Epub 2013 Jun 3.

3. Matsumura Y, Fukuda S, Tran H, et al. Geometry of the proximal isovelocity surface area in mitral regurgitation by 3-dimensional color Doppler echocardiography: difference between functional mitral regurgitation and prolapse regurgitation. Am Heart J. 2008 Feb;155(2):231-238. doi:10.1016/j.ahj.2007.09.002. Epub 2007 Oct 25.

9. Correct Answer: A. Severe acute MR secondary to traumatic PM rupture

Rationale: Torn PM can be seen moving from the left ventricle to the left atrium and back during the cardiac cycle. Even though CD may underestimate the severity of MR in the acute setting, as well as in cases of an eccentric jet, here CD is consistent with severe posteriorly (and superiorly) directed MR. Most cases of unilateral pulmonary edema are right-sided. However, whenever unilateral left-sided pulmonary edema is seen, the cause is very frequently a posteriorly directed MR jet. This can be achieved either by a prolapse of the anterior leaflet or by tethering of the posterior leaflet, with the former being more common in cases of acute MR. Acute MR secondary to blunt chest trauma is more often due to chordae rupture, while acute MR 2 to 5 days after an acute MI is more likely to be secondary to PM rupture.

1. Thomas B, Durant E, Barbant S, Nagdev A. Repeat point-of-care echocardiographic evaluation of traumatic cardiac arrest: a new paradigm for the emergency physician. Clin Pract Cases Emerg Med. 2017 May 23;1(3):194-196. doi:10.5811/cpcem.2017.2.33021.

10. Correct Answer: D. It is likely that LA enlargement is premorbid in this patient with acute MR.

Rationale: Even though measurement of LA AP diameter in PLAx as a single measure of LA size is disarranged, in this case it is obviously and severely dilated at least 4.7 cm (upper limit of normal for women is 3.8 cm).

Clinical presentation of unilateral right-sided pulmonary edema and hypotension is very much consistent with acute MR. Bilateral pulmonary edema in cases of acute MR is more common and cases of unilateral edema present a significant diagnostic challenge. When unilateral pulmonary edema is present, it is more commonly right-sided and when secondary to acute eccentric MR, it is usually caused by a flail posterior leaflet. Acute flail leaflet may be secondary to chord rupture or to PM rupture. In this case, a chord can be seen flying between the left atrium and the left ventricle in the zoomed-in A4 view. Etiologies of chordae rupture include:

Mobility of the MV leaflets does not show signs of fibrosis or calcification and is not restricted, which makes rheumatic MV disease unlikely. (See Figure 25.40.)

1. Ravi V, Rodriguez J, Doukky R, Pyslar N. Acute mitral regurgitation: the dreaded masquerader. CASE (Phila). 2018 Jan 3;2(1):12-15. doi:10.1016/j.case.2017.10.002.

11. Correct Answer: B. Holosystolic regurgitation of chronic central MR in a patient with pulmonary edema who is hemodynamically stable

Rationale: Assumptions behind the use of relative MR jet area are:

1. Dudzinski DM, Hung J. Echocardiographic assessment of ischemic mitral regurgitation. Cardiovasc Ultrasound. 2014 Nov 21;12:46. doi:10.1186/1476-7120-12-46.

2. Mitral valve disease. In: Armstrong WF, Ryan T, eds. Feigenbaum’s Echocardiography. 8th ed. Wolters Kluwer; 2019.

3. Zoghbi WA, Adams D, Bonow RO, et al. Recommendations for noninvasive evaluation of native valvular regurgitation: a report from the American Society of Echocardiography developed in collaboration with the Society for Cardiovascular Magnetic Resonance. J Am Soc Echocardiogr. 2017 Apr;30(4):303-371. doi:10.1016/j.echo.2017.01.007.

12. Correct Answer: E. None of the above

Rationale: Both A and B are velocities, not time, so may not be correct.

D marks the time point when velocity has decreased from its peak to half its value. Note that this is not pressure half-time. P½T is the time it takes for the pressure, not the velocity, to fall to 50% of its value.

From modified Bernoulli equation, ΔP = 4 × V², and so . Consequently,

In English, pressure half-time is achieved at the point where velocity has dropped to 0.71 of its peak value.

Nonetheless, Answer C is wrong because the deceleration slope used to derive these values is incorrect. (See Figures 25.15 and 25.41.)

Note that the E-wave has two distinct slopes, the earlier one being much steeper. When such morphology is present, it is the later slope that should be used to obtain pressure half-time and deceleration time, as shown in Figures 25.15 and 25.41. Note also that the V_max value used for the calculations is the point of the intersection of the slope with the spectral graph, not the actual maximal velocity of the flow.

1. Baumgartner H, Hung J, Bermejo J, et al. Echocardiographic assessment of valve stenosis: EAE/ASE recommendations for clinical practice. J Am Soc Echocardiogr. 2009 Jan;22(1):1-23.

13. Correct Answer: D. Cases 1 and 2 show MS.

Rationale: Patients in cases 1 and 2 both have restricted MV opening due to MS. In case 3 the valve itself is normal, but the leaflets are displaced apically (i.e., “tethered”) because of dilated cardiomyopathy. As a result, the valve leaflets do not coapt in systole, which results in MR. In diastole, the pressure in the left ventricle is high and the leaflets do not open all the way, but not because of any intrinsic valve pathology. Consequently, the anterior leaflet of the MV does not come close to the septum, as it does normally, resulting in increased EPSS—an index correlating with poor LV systolic function. Recognition of significant MS in patients presenting with pulmonary edema is extremely important clinically, as treatment options differ significantly, and a beta-blocker may be indicated. In significant MS of any etiology, posterior leaflet movement tends to be more restricted than that of the anterior leaflet.

The patient in case 1 has significant calcific MS. In MAC, the annulus is affected early and the disease then progresses distally toward the tips of the leaflets. Note that in this case the only mobile part of the anterior leaflet is its tip, while the base of the leaflet is fixed. In the industrialized world, MAC has replaced RHD as the leading cause of MS. (See Figure 25.42.)