The Importance of Lung Ultrasonography in the Assessment of Severity of Mitral Stenosis

BACKGROUND: This study investigated the relationship between mitral stenosis (MS) severity and B-line counts on lung ultrasonography (US) and their predictive value for PMBV requirement. METHODS: A total of 105 patients (70 MS, 35 controls) underwent transthoracic echocardiography (ECHO) and lung US using a 28-point protocol. Patients performed an exercise test to 85% of their predicted heart rate, followed by repeat imaging. B-line changes were analyzed by MS severity and symptoms. RESULTS: MS patients had significantly more B-lines than controls (p < 0.001). No significant difference was found between mild and moderate-severe MS at baseline. In moderate-severe MS, symptomatic patients had more B-lines than asymptomatic patients, both at rest and post-exercise (p = 0.02 and p = 0.002, respectively). An increase >3 B-lines in the left hemithorax after exercise predicted percutaneous mitral balloon valvuloplasty (PMBV) with 85.7% sensitivity and 66.2% specificity (AUC 0.69, p = 0.006). CONCLUSIONS: Lung US assessment of B-lines may assist in determining the optimal timing for intervention in MS, particularly in asymptomatic severe and symptomatic mild-to-moderate cases, where conventional ECHO findings may be inconclusive.