Mitral Stenosis in Rheumatic Heart Disease: X-Ray Findings in the Four Chamber View

Rheumatic heart disease often leads to valvular complications, with isolated mitral stenosis being one of the most common manifestations. When evaluating this condition using X-ray imaging, particularly in the four-chamber view, several distinct radiographic features become apparent. These findings are crucial for early diagnosis and effective management of the disease.

Characteristic X-Ray Features in the Posteroanterior View

In the posteroanterior (PA) projection, the cardiac silhouette typically exhibits a "pear-shaped" appearance. This is primarily due to the enlargement of the left atrium and right ventricle. The aortic knob appears diminished, while the pulmonary artery segment is prominently convex. Additionally, the left atrial appendage may project laterally, contributing to the overall contour of the heart. A double density sign may be visible along the right heart border, suggesting biatrial enlargement. The apex of the heart may also appear elevated due to diaphragmatic displacement.

Signs of Pulmonary Involvement

Secondary pulmonary changes are commonly observed in patients with mitral stenosis. These include pulmonary congestion and interstitial edema, which are reflected in the radiographic image as increased vascular markings and hazy lung fields. These findings indicate elevated left atrial pressure and impaired blood flow through the mitral valve.

Findings in the Right Anterior Oblique View

In the right anterior oblique (RAO) projection, an important diagnostic clue is the posterior displacement and deepening of the esophageal indentation caused by left atrial enlargement. This occurs as the enlarged left atrium exerts pressure on the esophagus, shifting it backward and creating a more pronounced impression visible on imaging.

Left Anterior Oblique View Observations

From the left anterior oblique (LAO) perspective, radiologists may observe an upward displacement of the left main bronchus due to cardiac enlargement. Furthermore, the lower portion of the heart's anterior border may appear more pronounced, indicating structural changes in the left ventricular outflow tract or surrounding areas.

Lateral View Assessment

In the lateral projection, a rounded or bulging contour along the posterior cardiac border is often noted. This reflects the anatomical changes associated with left atrial expansion and may help in assessing the severity of the stenosis.

Additional Diagnostic Considerations

Mitral valve calcification is another key radiographic feature that may be visible, especially in long-standing cases of rheumatic mitral stenosis. The presence of calcification not only supports the diagnosis but also suggests chronic disease progression.

These X-ray findings, when interpreted in conjunction with clinical symptoms and echocardiographic data, provide a comprehensive overview of the structural changes in the heart caused by isolated mitral stenosis in rheumatic heart disease. Early detection through imaging plays a vital role in guiding therapeutic decisions and improving patient outcomes.