1. Correct Answer: A. Flattening of IVS is maximal at end systole for pressure overload and at end diastole for volume overload.

Rationale: In the situation of right ventricular pressure overload, the IVS is shifted to the left side during the entire cardiac cycle with maximal flattening at the end systole, when pressure in the right ventricle is at its highest level. In the situation of right ventricular volume overload, the IVS is shifted mainly during mid- to end diastole when the right ventricle is being volume loaded. This flattening is reversed during systole-sparing left ventricular deformation at end systole. However, paradoxical systolic septal motion from left to right can be seen.

1. Harjola VP, Mebazaa A, Celutkiene J, et al. Contemporary management of acute right ventricular failure: a statement from the Heart Failure Association and the Working Group on Pulmonary Circulation and Right Ventricular Function of the European Society of Cardiology. Eur J Heart Fail. 2016;18(3):226-241.

2. Naeije R, Badagliacca R. The overloaded right heart and ventricular interdependence. Cardiovasc Res. 2017;113(12):1474-1485.

2. Correct Answer: D. Right ventricular pressure overload yields an eccentricity index <1 at end diastole and end systole

Rationale: The eccentricity index has been described as a modality to evaluate IVS motion through the cardiac cycle (Figure 23.1).

The eccentricity index is the ratio of the vertical diameter parallel to the IVS over the horizontal diameter perpendicular to the IVS of the left ventricle taken from a transgastric short-axis TEE view or a parasternal short-axis transthoracic echocardiography (TTE) view. The vertical diameter corresponds to the anterior to inferior diameter and the horizontal diameter corresponds to the septal to lateral diameter. These diameters are measured at end diastole and at end systole. Under normal pressure- and volume-loading conditions, the eccentricity index is 1 in order to describe the circular left ventricular geometry as well as the curvature of the IVS. This ratio will increase over 1 during systole and diastole in situations of elevated right ventricular pressure. In situations of volume overload, the ratio will be >1 only during end diastole, where the right ventricle is being overfilled and distended.

1. Ryan T, Petrovic O, Dillon JC, Feigenbaum H, Conley MJ, Armstrong WF. An echocardiographic index for separation of right ventricular volume and pressure overload. J Am Coll Cardiol. 1985;5(4):918-927.

3. Correct Answer: D. There are three papillary muscles in the right ventricle.

Rationale: The right ventricle presents anatomic features that allow differentiation from the left ventricle. Among them are apical displacement of the right septal atrioventricular valve leaflet that is also formed by three leaflets, presence of a moderator band in the right ventricle, presence of three papillary muscles, and a frank separation of inflow and outflow. The thickness of the right ventricle is typically less than the left ventricle but can be the same in some pathologic conditions.

1. Haddad F, Hunt SA, Rosenthal DN, Murphy DJ. Right ventricular function in cardiovascular disease, part I: Anatomy, physiology, aging, and functional assessment of the right ventricle. Circulation. 2008;117(11):1436-1448.

2. Haddad Fo, Doyle R, Murphy DJ, Hunt SA. Right Ventricular function in cardiovascular disease, Part II. Circulation. 2008;117(13):1717-1731.

3. Sanz J, Sánchez-Quintana D, Bossone E, Bogaard HJ, Naeije R. Anatomy, function, and dysfunction of the right ventricle. J Am Coll Cardiol. 2019;73(12):1463-1482.

4. Correct Answer: A. Right ventricular base diameter of 45 mm

Rationale: Right ventricular dimensions should always be measured at end diastole to reflect the largest measurement (Figure 23.2).

Multiple views and alignments should be used in order to get the largest possible diameter. The right ventricular base diameter (RVD1) corresponds to the maximal transverse dimension in the basal one-third of the right ventricular inflow. Values >41 mm correspond to right ventricular dilatation. Mid-cavity right ventricular linear diameter (RVD2) corresponds to the transverse right ventricular diameter in the middle third of right ventricle inflow, approximately halfway between the maximal basal diameter and the apex, at the level of papillary muscles. Values >35 mm correspond to dilatation. Right ventricular length or longitudinal dimension (RVD3) corresponds to the distance between the tricuspid plane and the apex. Values >83 mm refer to dilatation.

1. Lang RM, Badano LP, Mor-Avi V, et al. Recommendations for cardiac chamber quantification by echocardiography in adults: an update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging. J Am Soc Echocardiogr. 2015;28(1):1-39 e14.

2. Rudski LG, Lai WW, Afilalo J, et al. Guidelines for the echocardiographic assessment of the right heart in adults: a report from the American Society of Echocardiography endorsed by the European Association of Echocardiography, a registered branch of the European Society of Cardiology, and the Canadian Society of Echocardiography. J Am Soc Echocardiogr. 2010;23(7):685-713; quiz 86-88.

5. Correct Answer: A. 28 mm Hg

Rationale: Using the modified Bernoulli equation, P = 4 V², where P stands for pressure and V for velocity, the pressure gradient between the right atrium and right ventricle can be calculated. Using continuous-wave Doppler of the TR jet, the difference in pressure between the right ventricle and the right atrium can be calculated with the following modified Bernoulli equation: P = 4 (TR_{peak velocity})² where P corresponds to a pressure difference on which the RAP must be added to obtain an estimation of the right ventricular systolic pressure. From the TR, the probability of pulmonary hypertension can be estimated based on the maximal TR jet velocity; ≤2.8 m/s being low probability, 2.9-3.4 m/s being intermediate probability, and >3.4 m/s being high probability. MPAP can be estimated from the SPAP using the following formula: MPAP = (0.61 · SPAP) + 2 mm Hg. See Figure 23.3 for additional details.

1. Bossone E, D’Andrea A, D’Alto M, et al. Echocardiography in pulmonary arterial hypertension: from diagnosis to prognosis. J Am Soc Echocardiogr. 2013;26(1):1-14.

2. Parasuraman S, Walker S, Loudon BL, et al. Assessment of pulmonary artery pressure by echocardiography – a comprehensive review. Int J Cardiol Heart Vasc. 2016;12:45-51.

6. Correct Answer: B. TR jet peak velocity has to be squared via Bernoulli equation to convert velocity toward a pressure

Rationale: Doppler evaluation of TR allows a reliable estimation of pulmonary artery pressure.

The bedside echocardiographer must remember that velocity measurements are angle dependent. Thus, optimal TR jet velocity should be taken after interrogation in multiple, sometimes off-axis views, in order to obtain the best spectral Doppler envelope and maximal velocity as well as the best alignment between regurgitant flow and continuous-flow Doppler interrogation beam.

In the absence of pulmonary flow obstruction or significant pressure gradient between RVOT and pulmonary artery, TR peak velocity squared has a linear positive correlation with SPAP measured by right heart catheterization. In situations of pulmonary valve stenosis or RVOT obstruction, pulmonary artery pressure based on TR peak velocity and the modified Bernoulli equation will estimate the right ventricular systolic pressure but overestimate the pulmonary artery systolic pressure. If this is the case, peak pressure gradient across the pulmonary valve or the RVOT should be subtracted from the measured pulmonary artery systolic pressure.

It is also important to mention that in the presence of severe TR with a large color-flow regurgitant jet due to a large effective regurgitation orifice area (EROA), the TR peak velocity may not reflect the true gradient between the right ventricle and the RAP due to early equalization of right ventricle and RAP.

1. Bossone E, D’Andrea A, D’Alto M, et al. Echocardiography in pulmonary arterial hypertension: from diagnosis to prognosis. J Am Soc Echocardiogr. 2013;26(1):1-14.

7. Correct Answer: B. 44 mm Hg

Rationale: Evaluation of PR from a parasternal short-axis view allows estimation of both MPAP and diastolic pulmonary artery pressure (DPAP). In this view, color-flow Doppler interrogation of PR will permit estimation of MPAP from peak early diastolic velocity, whereas DPAP will be estimated from end-diastolic velocities. Using the modified Bernoulli equation (P = 4V²), PR peak early diastolic velocity and PR end-diastolic velocity can, respectively, be placed in the equation to find the pressure difference between the pulmonary artery and the right ventricle during diastole. From these values, addition of the RAP will result in MPAP and DPAP, assuming that RAP is equal to right ventricular end-diastolic pressure.

MPAP = 4(PR_{peak early diastolic velocity})² + RAP

MPAP= 4 (3 m/s)² + 8 mm Hg

MPAP= 44 mm Hg

DPAP = 4(PR_{end-diastolic velocity})² + RAP

DPAP= 4 (1 m/s)² + 8 mm Hg

DPAP= 12 mm Hg

Common pitfalls using this technique are misalignment of the PR Doppler signal and presence of constrictive or restrictive physiology that will result in shorter PR signal due to early equalization of pulmonary artery and right ventricular pressure.

MPAP can also be calculated using the SPAP obtained from Bernoulli equation and TR peak velocity and the DPAP obtained from the method previously mentioned using the following equation: MPAP= 2/3 · DPAP + 1/3 · SPAP. Lastly, MPAP can also be estimated from velocity-time integral (VTI) obtained from continuous-wave Doppler TR profile tracing. MPAP will thus be obtained by adding RAP to mean pressure obtained from VTI_TR, which represents mean right ventricular systolic pressure.

1. Bossone E, D’Andrea A, D’Alto M, et al. Echocardiography in pulmonary arterial hypertension: from diagnosis to prognosis. J Am Soc Echocardiogr. 2013;26(1):1-14.

2. Parasuraman S, Walker S, Loudon BL, et al. Assessment of pulmonary artery pressure by echocardiography – a comprehensive review. Int J Cardiol Heart Vasc. 2016;12:45-51.

8. Correct Answer: A. Large and eccentric TR

Rationale: The right ventricular contractility can be estimated from intraventricular dP/dt. In order to use dP/dt on echocardiography, TR must be present and must be interrogated with continuous Doppler during isovolumetric contraction when there is no significant change in RAP and before pulmonary valve opening. By using a time interval between 0.5 (=1 mm Hg) and 2 (=16 mm Hg) m/s on the Doppler velocity spectrum, the numerator becomes 15 mm Hg (16 mm Hg – 1 mm Hg) using Bernoulli equation. Thus, dP/dt = 15 mm Hg/dt, where dt represents the time lapse between 0.5 and 2 m/s on the Doppler spectrum. A dP/dt value higher that 400 mm Hg/s or a duration of dt ≤ 37.5 ms when the velocity goes from 1 to 2 m/s corresponds to normal values, whereas dP/dt lower than 400 mm Hg/s (dt >37.5 ms) corresponds to reduced right ventricular systolic function. Finally, eccentric, trivial, or severe TR and presence of regional wall motion abnormality might give wrong estimates of the right ventricular systolic function.

1. Rudski LG, Lai WW, Afilalo J, et al. Guidelines for the echocardiographic assessment of the right heart in adults: a report from the American Society of Echocardiography endorsed by the European Association of Echocardiography, a registered branch of the European Society of Cardiology, and the Canadian Society of Echocardiography. J Am Soc Echocardiogr. 2010;23(7):685-713; quiz 86-88.

9. Correct Answer: C. Hypervolemia

Rationale: Dynamic RVOT obstruction can be seen in up to 4% of patients undergoing cardiac surgery. It is defined by a difference of at least 6 mm Hg between systolic right ventricular pressure and SPAP. Significant RVOT obstruction is defined by a pressure gradient of at least 25 mm Hg. This causes end-systolic obliteration of the RVOT on echocardiography. This condition can be appreciated with the use of M-mode in mid-esophageal right ventricular inflow-outflow view. Management strategies of this condition are similar to left ventricular outflow tract obstruction and include increase in preload, decrease in inotropic support, and decrease in heart rate when possible. Right ventricular dysfunction can be from mechanical compression secondary to mediastinal tumors, blood clots, surgical manipulation, left-sided tension pneumothorax, or any extrinsic condition that reduces the size of the RVOT. The treatment consists of removing the extrinsic cause of obstruction.

1. Denault AY, Chaput M, Couture P, Hébert Y, Haddad F, Tardif J-C. Dynamic right ventricular outflow tract obstruction in cardiac surgery. J Thorac Cardiovasc Surg. 2006;132(1):43-49.

2. Raymond M, Gronlykke L, Couture EJ, et al. Perioperative right ventricular pressure monitoring in cardiac surgery. J Cardiothorac Vasc Anesth. 2019;33(4):1090-1104.

3. Rochon AG, L’Allier PL, Denault AY. Always consider left ventricular outflow tract obstruction in hemodynamically unstable patients. Can J Anaesth. 2009;56(12):962-968.

10. Correct Answer: C. A global appraisal of right ventricular systolic function

Rationale: RVFAC is defined as the difference between end-diastolic and end-systolic right ventricular area compared to the end-diastolic right ventricular area (RV end-diastolic area – RV end-systolic right ventricular area)/end-diastolic right ventricular area × 100. RVFAC is obtained by tracing the right ventricular endocardium in diastole and systole from the lateral portion of the tricuspid annulus, along the lateral wall to the apex, and then to the septal portion of the tricuspid annulus, all along the IVS (Figure 23.4).

Right ventricular wall must be traced beneath the trabeculations. The lower reference value for normal right ventricular systolic function for RVFAC is 35%. Some references grade severity of right ventricular dysfunction based on RVFAC according to the following: mild (RVFAC 25%-31%), moderate (RVFAC 18%-24%), and severe (RVFAC < 18%). However, recent iteration of the American Society of Echocardiography does not refer to any such classification. RVFAC provides an estimate of global right ventricular systolic function as it has been shown to correlate with right ventricular ejection fraction by magnetic resonance imaging. It has also been found to be an independent predictor of heart failure, sudden death, stroke, and/or mortality in studies of patients after pulmonary embolism and myocardial infarction.

1. Lang RM, Badano LP, Mor-Avi V, et al. Recommendations for cardiac chamber quantification by echocardiography in adults: an update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging. J Am Soc Echocardiogr. 2015;28(1):1-39 e14.

2. Lang RM, Bierig M, Devereux RB, et al. Recommendations for chamber quantification: a report from the American Society of Echocardiography’s Guidelines and Standards Committee and the Chamber Quantification Writing Group, developed in conjunction with the European Association of Echocardiography, a branch of the European Society of Cardiology. J Am Soc Echocardiogr. 2005;18(12):1440-1463.

3. Rudski LG, Lai WW, Afilalo J, et al. Guidelines for the echocardiographic assessment of the right heart in adults: a report from the American Society of Echocardiography endorsed by the European Association of Echocardiography, a registered branch of the European Society of Cardiology, and the Canadian Society of Echocardiography. J Am Soc Echocardiogr. 2010;23(7):685-713; quiz 86-88.

11. Correct Answer: C. Adequate right ventricular linear measurements should be taken from an apical four chamber showing the largest possible right ventricular basal diameter while presenting the left ventricular apex in the center of the scanning sector.

Rationale: There is a greater interobserver variability when visual assessment of right ventricular chamber size and function is made over direct quantification. The conventional transthoracic apical four-chamber view focused on the left ventricle can induce considerable variability in how the right heart is partitioned. Thus, linear right ventricular dimensions and areas are prone to variations with only minor rotations in transducer position. Right ventricular dimensions are best estimated from an apical four-chamber view dedicated to the right ventricle obtained by lateral or medial transducer rotation. Adequate right ventricular linear measurements should ideally be taken from an apical four chamber showing the largest possible right ventricular basal diameter while presenting the left ventricular apex in the center of the scanning sector. Part of the right ventricular lateral wall might not be well defined due to either its size or its position behind the sternum. Two-dimensional right ventricular measurements are challenging essentially due to its complex geometry and the lack of specific right-sided anatomic landmarks to be used as reference points.

1. Lang RM, Badano LP, Mor-Avi V, et al. Recommendations for cardiac chamber quantification by echocardiography in adults: an update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging. J Am Soc Echocardiogr. 2015;28(1):1-39 e14.

2. Ling LF, Obuchowski NA, Rodriguez L, Popovic Z, Kwon D, Marwick TH. Accuracy and interobserver concordance of echocardiographic assessment of right ventricular size and systolic function: a quality control exercise. J Am Soc Echocardiogr. 2012;25(7):709-713.

12. Correct Answer: A. Moderate-to-severe right ventricular free wall hypokinesis with normal or hyperdynamic wall motion of the right ventricular apex

Rationale: The McConnell sign consists of moderate-to-severe basal and mid-lateral hypokinesis with normal or hyperdynamic wall motion of the right ventricular apex in situations where a pulmonary embolism is suspected. This sign is specific for acute right ventricular failure though not only specific to pulmonary embolism. For a diagnosis of pulmonary embolism, this echocardiographic finding yields a sensitivity of 77% and a specificity of 94% in hospitalized patients with RV dysfunction from any cause. The positive predictive value of this finding for the diagnosis of pulmonary embolism is described to be 71% and the negative predictive value of 96% for an overall diagnostic accuracy of 92%. One explanation for this finding is believed to be that in the presence of pulmonary embolism, the left ventricle can become hyperdynamic and create tethering of the right ventricular apex rendering the preserved or hyperdynamic right ventricular apex. Also, in the situation of acute increases in right ventricular afterload, the right ventricle may assume a more spherical shape to equalize regional wall stress when subjected to an abrupt increase in afterload. A more spherical shape with systolic contraction would correspond to a bulging of the mid-right ventricular lateral wall relative to the apex and base. Lastly, increased right ventricular pressures and wall stress can decrease right ventricular coronary artery perfusion pressure and create localized ischemia of right ventricular lateral wall.

1. McConnell MV, Solomon SD, Rayan ME, Come PC, Goldhaber SZ, Lee RT. Regional right ventricular dysfunction detected by echocardiography in acute pulmonary embolism. Am J Cardiol. 1996;78(4):469-473.