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Rao. Vessel Plus 2022;6:22 https://dx.doi.org/10.20517/2574-1209.2021.105 Page 13 of 24

normal fashion. The pulmonary component of the 2nd sound is usually normal, although it may be loud in
patients with elevated PA pressures or increased pulmonary vascular resistance. A moderately loud 3rd
sound is auscultated if MR is moderate to severe in degree. A grade I-II/VI mid-diastolic flow rumble is
auscultated at the apex in patients who have moderate to severe in degrees of MR. This mid-diastolic
murmur is heard better with the stethoscope’s bell. Mid-diastolic murmur is indicative of large flow across
the mitral valve and does not imply additional mitral stenosis. The BP and peripheral pulses are generally
within normal limits.

ECG does not show abnormalities in subjects with mild MR. LA enlargement and LV hypertrophy may be
seen in patients with moderate to severe MR. Chest X-ray is normal in patients with mild MR. Enlargement
of the heart due to dilated LA and LV may be seen in patients with moderate to severe MR. The degree of
cardiomegaly is in proportion to the magnitude of MR. M-mode and 2D echo studies are of value in
quantifying the sizes of the LA and LV. As a rule, the LA and LV sizes are proportional to the amount of
MR. LV shortening fraction (SF) is usually normal. In some patients, the normal SF value is due to the LV
emptying into the low resistance LA instead of the aorta, which has high peripheral vascular resistance. If
the LV systolic function worsens, the SF will decrease. Color Doppler study is helpful in confirming MR.

Tricuspid regurgitation
The holosystolic murmur of TR is auscultated at the lower left sternal border. Typically, the intensity of the
murmur changes with the respiratory cycle (increases during inspiration) and hence is dissimilar to the
murmur of ventricular septal defect. In addition, the murmur of TR sounds more “superficial” and
“scratchy”. However, the TR murmur is less frequently seen than a VSD murmur. The TR murmur is heard
in association with structural tricuspid valve diseases such as Ebstein’s anomaly of the tricuspid valve and
dysplastic tricuspid valve. Or, it is due to functional abnormality of the tricuspid valve, related to RV
dysfunction in babies with myocardial ischemia syndrome or marked elevation of PA or RV systolic
pressures. Accordingly, it appears that other, more severe heart disease coexists in the subjects with TR.
Increased “v” waves in the jugular venous pulse may be seen, and systolic pulsations in the liver may be felt.
The RV impulse is increased. No thrills are usually felt. The character of the 2nd sound is related to the
main cardiac abnormality producing TR. Mid-diastolic flow murmur of grade I-II/VI intensity is heard best
at the lower left sternal border if the degree of TR is more than moderate. Mid-diastolic murmur is due to
augmented blood flow via the tricuspid orifice.

ECG demonstrates RVH and frequently reflects the primary disease process. Chest roentgenogram
generally shows an enlarged cardiac silhouette, and the right atrial shadow is prominent. Echo-Doppler
studies show RV volume overloading. The echo findings unravel the primary disease entity. Color Doppler
imaging clearly shows the TR.

Diastolic murmurs
If the murmur is placed in between the 2nd and 1st heart sounds, it is described as a diastolic murmur
[Figure 3]. These murmurs are classified as follows: (1) early; (2) mid; and (3) late [Figure 3]. Late diastolic
murmurs are generally called presystolic murmurs. While this classification is arbitrary, such subdivision is
considered clinically useful.

Early diastolic murmurs
Early diastolic murmurs usually have a decrescendo character (Figure 3; top) and are produced by
insufficiency of aortic or pulmonary valves. Their causes are enumerated in [Table 6]. The precordial site
where the murmur is heard best, murmur’s pitch, and at times, careful history and findings on physical