The patient's position should be supine left side down.
This case presents an example of moderate mitral stenosis. The first heart sound is increased in intensity, while the second heart sound is normal and unsplit. A diamond-shaped low-frequency murmur follows the opening snap. There is a second murmur in late diastole caused by the contraction of the left atrium. Use the bell of the stethoscope to hear this murmur.
In the animation, observe the turbulent blood flow from the left atrium into the left ventricle. Also, observe the moderately thickened mitral valve leaflets and the moderately enlarged left atrium.
This condition is most commonly due to rheumatic heart disease.