Which finding might indicate worsening mitral stenosis on an echocardiogram?

Worsening mitral stenosis can lead to an increase in left atrial pressure, which is a key indicator of the disease's progression. In mitral stenosis, the narrowing of the mitral valve impedes normal blood flow from the left atrium to the left ventricle during diastole. As a result, blood accumulates in the left atrium, leading to elevated pressure levels. This increased pressure can then be detected on echocardiography and is reflective of the increased workload on the left atrium due to the obstruction.

In contrast, a decrease in left atrial size would generally suggest improvement in the hemodynamic status or decreased pressure in the left atrium, which is not consistent with worsening stenosis. Normal left ventricular size does not specifically indicate changes in mitral valve function and could remain stable despite the severity of mitral stenosis. A decrease in interventricular septum thickness does not typically relate to mitral stenosis and is more associated with changes in ventricular hypertrophy or volume status. Therefore, the indication of increasing left atrial pressure serves as a critical marker for the progression of mitral stenosis.