The importance of lung ultrasonography in the evaluation of the severity of mitral stenosi̇s

Objective: Our aim in this study is to evaluate the routine echocardiographic parameters that can be measured non-invasively using echocardiography (ECHO) during the routine check-ups of patients with mild and moderate-severe mitral stenosis (MD) who are followed up in the cardiology clinic, as well as the lung ultrasound (LUS) measured after the baseline lung ultrasound and the stress test. The predictive value of the change in the number and distribution of B lines in evaluating the severity of MD, other than standard echo parameters, will be investigated. Method: 70 MD patients followed in our clinic were included in the study. MD patients were divided into 2 groups: mild and moderate-severe MD. A total of 105 cases were included, including 35 control group patients who were examined at the cardiology outpatient clinic and did not have heart failure (HF) or additional valve pathology. Echocardiographic evaluation was performed using conventional echocardiography methods. Before the exercise test, patients underwent baseline LUS and the number and distribution of B lines were recorded. Heart rate and oxygen saturation were recorded before exercise. The patients were subjected to an exercise test to reach 85 % of their basal heart rate. Following post-exertion heart rate and oxygen saturation, mitral valve gradients and pulmonary artery pressure were re-evaluated with ECHO. After exercise, LUS was repeated and the distribution and number of B lines were recorded again. The relationship between the change in the number and distribution of B lines before and after exercise and the severity of MD was evaluated among all three groups. Results: Baseline demographic characteristics, including age, gender, diabetes, hypertension, coronary artery disease (CAD), and body mass index (BMI), were similar in the MD and control groups. After exercise, the number of B lines increased more in the right and left hemithorax than in the control group. [(8 (11.5), 0.5 (3)), p<0.0001; (4(13), 0(2)), p<0.0001]. The total number of B lines in both hemithoraxes increased significantly more in the MD group [14(19,25), 2(4,25); p<0.0001]. A significant increase in the number of B lines was observed in the MD group compared to the control group. However, no significant difference was observed between the moderate-severe MD and mild MD groups. [(9(12), 7(10.5), 0(1); p<0.001) ; (10.5(24.7), 4 (9.5) , 0 (1); p<0.001)]. In the moderate-severe MD group, the number of B lines was significantly higher in symptomatic patients than in asymptomatic patients, both before and after exercise [(11(42), 5(10); p:0.02); (45(92), 12(21); p:0.002)]. In the evaluation performed on the left hemithorax, there was a difference of >3 B lines before and after exercise, indicating 85.7% sensitivity (95% CI 57.2-98.2%), 66.2% specificity (95% CI 55.5-76%, 0) predicts mitral balloon valvuloplasty (MBVP). The positive predictive value is 28.6% (95% CI 21.8- 36.5), the negative predictive value is 96.7% (95% CI 89-99.1). AUC: 0.69 (95% CI 0.59-0.78) p:0.006. Conclusion: The increase in the number of B lines with effort was observed more in the MD group than in the control group. However, the increase did not correlate with valve severity. In the moderate-severe MD group, the number of B lines was significantly higher in symptomatic patients than in asymptomatic patients, both before and after exercise. Our study is important in that LUS plays a complementary role in the follow-up of patients with MD and in the evaluation of intervention time. Keywords: Mitral stenosis, Subclinical congestion, Lung ultrasonography, B line