AV, Aortic valve Tricuspid Valve Disease Tricuspid regurgitation in the setting of RHD is most commonly functional and is the result of advanced left-sided pathology and pulmonary hypertension Organic tricuspid valve disease that results from direct rheumatic inflammation is less common; it almost always coexists with mitral and/or AV involvement and is considered to be a marker of severity of RHD Like the MR, tricuspid valve regurgitation may also progress to stenosis with leaflet thickening, chordal shortening, and commissural fusion Pulmonary Valve Disease Pulmonary valve involvement in RHD is exceptional but has been described Grading of Valvar Severity Significant limitations exist with regard to grading the severity of rheumatic valvar dysfunction by echocardiography This relates to the fact that multivalve disease is common and often manifests as mixed valve disease—concomitant stenosis and regurgitation Even in the setting of pure MR, evaluation can be challenging, as the regurgitant jet is typically very eccentric and wall hugging, and multiple jets are common AR often arises as a result of leaflet prolapse, resulting in eccentric regurgitant jets The American Society of Echocardiography recommendations for evaluating the severity of native aortic and mitral valvar regurgitation with two-dimensional (2D) and Doppler echocardiography are detailed in Chapters 34 and 44.39 These guidelines, however, do not detail how to differentiate trivial or physiologic regurgitation from mild/pathologic regurgitation, since these findings in degenerative or congenital heart disease have no clinical significance However, in the setting of RHD, the prescription of long-term secondary prophylaxis in the form of three to four weekly intramuscular injections of benzathine penicillin may depend on whether the regurgitation is trivial or mild For this reason, the 2012 World Heart Federation echocardiographic diagnostic criteria were established with an aim to clearly define how to differentiate physiologic from mild pathologic regurgitation (see Box 55.1).22 Monitor Progression/Resolution Serial echocardiography allows for the monitoring of disease progression or resolution In addition to assessing valvar morphology and grading the severity of valvar dysfunction, serial measurements of left atrial size, LV size, and LV volume using 2D (M-mode, area/length, and Simpson biplane methods) or newer three-dimensional (3D) modalities allow for optimizing medical management and the timing of surgery Serial assessment of ventricular function and estimation of pulmonary artery pressure are required It is important to note that in the setting of significant mitral and/or AR, fractional shortening or ejection fraction are poor surrogates for cardiac contractility due to the altered loading conditions; therefore they may underestimate cardiac impairment Load-independent measures, such as stress velocity index, may correlate more closely with the state of cardiac contractility in these circumstances.12 Guide to the Nature of Cardiosurgical Intervention Echocardiographic parameters guide the timing of surgery in acute and chronic RHD Two-dimensional and 3D imaging can accurately identify the mechanism of valvar dysfunction; evaluate the patient's suitability for percutaneous intervention; and guide surgical mitral, aortic, and tricuspid valve repair strategies (Fig 55.10) FIG 55.10 Three-dimensional echocardiographic image of rheumatic heart disease of the mitral valve