Q. Explain Tricuspid regurgitation?

Though tricuspid regurgitation is a common valvular abnormality on echocardiography rarely is it due to primary organic disease.

Secondary or functional tricuspid regurgitation due to pulmonary hypertension of any cause, is much more common than primary tricuspid regurgitation. In these instances tricuspid valve structure is normal except for dilated tricuspid annulus. Right ventricular and right atrial dilatation further exaggerates this abnormality.

Primary causes or organic involvement of tricuspid regurgitation as opposed to its functional involvement are much less common. The common etiologies include rheumatic, traumatic, endocarditis, carcinoid, endomyocardial fibrosis and myxomatous valve prolapse. Rheumatic etiology is often accompanied by involvement of mitral valve. Similarly myxomatous degeneration is associated with mitral valve prolapse. Infective endocarditis is typically seen in drug addicts, but it is more commonly described with septic abortions and contaminated intra venous infusions in India. Endomyocardial fibrosis affecting right ventricular apex as well as mitral valve is confined to certain geographical regions. Tricuspid Regurgitation due to blunt injury chest can have a delayed presentation. Conduction abnormalities are often associated with traumatic tricuspid regurgitation. Ebstein's anomaly, a congenital heart disease is often associated with varying degrees of tricuspid regurgitation. Carcinoid valve disease is rare, and tricuspid valvular involvement is associated with hepatic metastasis only. Pulmonary valve also is often involved in this disease.