Left atrial and left ventricular strain dynamics with echocardiography in asymptomatic children with mitral regurgitation

Left atrial (LA) dilatation is a strong predictor of cardiovascular morbidity and mortality. Strain parameters evaluating LA functions have gained importance in assessing cardiovascular health. This study aimed to investigate the relationship between LA and left ventricular (LV) strain, using speckle-tracking echocardiography, and assess the impact of vena contracta on LV functioning in asymptomatic children with mitral regurgitation. We evaluated 45 asymptomatic mitral regurgitation patients, categorized as mild, moderate, and severe. LV strain was significantly lower in the moderate group (–17.8 ± 3.7%) and further reduced in the severe group (16 ± 2.1%) compared to the reference group (20.5 ± 6.2%). Conversely, LA reservoir strain was higher in the severe and moderate groups (38 ± 12.9% and 40.7 ± 9.5%, respectively) compared to the controls (31.3 ± 7.5%; p < 0.0001). The severe group also displayed a milder depression of contraction (12.2%) compared to the moderate group (13 ± 7.2%). In the moderate and severe groups, LV strain correlated significantly with vena contracta (r=–0.858; p = 0.04), with vena contracta emerging as the only independent predictor for LV longitudinal strain. ROC curve analysis indicated a cut-off value > 5.65 mm for vena contracta, which had a positive predictive value of 75% for predicting LV function impairment. In conclusion, this study emphasizes the significance of assessing LA and ventricular strain in asymptomatic children with mitral regurgitation. Furthermore, vena contracta with diameters greater than 5.6 mm may alert clinicians to the possibility of LV function impairment. These findings offer valuable insights for the follow-up and management of paediatric patients with mitral regurgitation, enabling early detection of potential complications and improved patient outcomes.