ESSENTIALS OF DIAGNOSIS
Frequently occurs in patients with pulmonary or cardiac disease with pressure or volume overload on the right ventricle.
Tricuspid valve regurgitation from pacemaker lead placement is becoming more common.
Systolic c-v wave in JVP.
Holosystolic murmur along left sternal border, which increases with inspiration.
Echocardiography useful in determining cause (low- or high-pressure tricuspid regurgitation).
The tricuspid valve apparatus differs in many ways from the mitral valve apparatus. Besides having three leaflets rather than two, the tricuspid valve has many chordae that attach to the RV endocardium rather than to discrete papillary muscles, and chordal attachments to the RV septum. Tricuspid valvular regurgitation often occurs whenever there is RV dilation from any cause. As tricuspid regurgitation increases, the RV size increases further pulling the valve open due to chordal and papillary muscle displacement. This, in turn, worsens the severity of the tricuspid regurgitation. In addition, the tricuspid annulus is shaped like a horse’s saddle. With RV failure, the annulus flattens and becomes elliptical, further distorting the relationship between the leaflets and chordal attachments. In most cases, the cause of the tricuspid regurgitation is the RV geometry (functional) and not primary tricuspid valve disease. An enlarged, dilated RV may be present if there is RV systolic hypertension from valvular or subvalvular pulmonary valve stenosis, pulmonary hypertension for any reason, in severe pulmonary valve regurgitation, or in cardiomyopathy. The RV may also be injured from an MI or may be inherently dilated due to infiltrative diseases (RV dysplasia or sarcoidosis). RV dilation often occurs secondary to left heart failure. Inherent abnormalities of the tricuspid valve include Ebstein anomaly (displacement of the septal and posterior, but not the anterior, leaflets into the RV), tricuspid valve prolapse, carcinoid plaque formation, collagen disease inflammation, valvular tumors, or tricuspid endocarditis. In addition, pacemaker lead valvular injury is an increasingly frequent iatrogenic cause.
The symptoms and signs of tricuspid regurgitation are identical to those resulting from RV failure due to any cause. As a generality, the diagnosis can be made by careful inspection of the JVP (see Table 10–1). The JVP waveform should decline during ventricular systole (the x descent). The timing of this decline can be observed by palpating the opposite carotid artery. As tricuspid regurgitation worsens, more and more of this x descent valley in the JVP is filled with the regurgitant wave until all of the x descent is obliterated and a positive systolic waveform will be noted in the JVP. An associated tricuspid regurgitation murmur may or may not be audible and can be distinguished from mitral regurgitation by the left parasternal location and an increase with inspiration (Carvallo sign). An S3 may accompany the murmur and is related to the high flow returning to the RV from the RA. Cyanosis may be present if the increased RA ...