What is the diagnosis for a patient with an opening snap and diastolic rumble heard best at the 4th ICS midclavicular line?

The presence of an opening snap followed by a diastolic rumble is characteristic of mitral stenosis. In mitral stenosis, the normal diastolic filling of the left ventricle is impeded due to narrowing of the mitral valve, which results in increased pressure in the left atrium. When the mitral valve opens, the abrupt halt of the valve leaflets contributes to the generation of the opening snap sound. This is particularly prominent in patients with rheumatic heart disease, which is a common cause of mitral stenosis.

The diastolic rumble occurs as a result of turbulent blood flow from the left atrium into the left ventricle during diastole, and its best auscultatory location – the 4th intercostal space along the midclavicular line – aligns with the position of the heart and where the left atrial pressure is transmitted best.

In contrast, aortic stenosis typically presents with a systolic ejection murmur rather than diastolic sounds. Tricuspid regurgitation would show a holosystolic murmur that is best heard along the left sternal border and would not typically be associated with an opening snap. Pulmonary stenosis primarily presents with