RESUMEN
Aims: Rheumatic mitral stenosis (MS) frequently leads to impaired left atrial (LA) function because of pressure overload, highlighting the underlying atrial pathology. Two-dimensional speckle tracking echocardiography (2D-STE) offers early detection of LA dysfunction, potentially improving risk assessment in patients with MS. This study aims to evaluate the predictive value of LA function assessed by 2D-STE for clinical outcomes in patients with MS. Methods and results: Between 2011 and 2021, patients with MS underwent LA function assessment using 2D-STE, with focus on the reservoir phase (LASr). Atrial fibrillation (AF) development constituted the primary outcome, with death or valve replacement as the secondary outcome. Conditional inference trees were employed for analysis, validated through sample splitting. The study included 493 patients with MS (mean valve area 1.1 ± 0.4 cm2, 84% female). At baseline, 166 patients (34%) had AF, with 62 patients (19%) developing AF during follow-up. LASr emerged as the primary predictor for new-onset AF, with a threshold of 17.9%. Over a mean 3.8-year follow-up, 125 patients (25%) underwent mitral valve replacement, and 32 patients (6.5%) died. A decision tree analysis identified key predictors such as age, LASr, severity of tricuspid regurgitation (TR), net atrioventricular compliance (C n), and early percutaneous mitral valvuloplasty, especially in patients aged ≤49 years, where LASr, with a threshold of 12.8%, significantly predicted adverse outcomes. Conclusion: LASr emerged as a significant predictor of cardiovascular events in this MS cohort, validated through a decision tree analysis. Patients were stratified into low- or high-risk categories for adverse outcomes, taking into account LASr, age, TR severity, and C n.
RESUMEN
Cardiomyopathy is a major cause of death in Chagas disease and early detection of cardiac involvement is essential. Myocardial strain is a reliable technique for assessment of subtle left ventricular (LV) contractility alterations. This study assessed LV global longitudinal strain (GLS) in a large Chagas disease population living in remote areas. Between 2015 and 2016, Chagas disease patients were selected in the northern of the Minas Gerais state. All patients underwent T. cruzi antibodies tests and those who had positive tests were included. A resting 12-lead ECG was recorded and classified using the Minnesota Code criteria. Echocardiography was performed at public health primary care units and speckle-tracking strain was analyzed offline. LV dysfunction was defined as ejection fraction (LVEF < 50%) and reduced GLS was defined as < 16% (absolute value). A total of 1387 patients were included, mean age of 60.0 ± 12.5 years, 68% were women, and 14% had LV dysfunction. Among patients with normal LVEF, 59% had impaired LV GLS. Overall, patients with impaired GLS were older, had more comorbidities and ECG abnormalities than those with normal GLS. The independent factors associated with reduced GLS were ST-T abnormalities (OR 1.954; 95% CI 1.027-3.718), QRS duration (OR 1.009; 95% CI 1.002-1.016), LVEF (OR 0.947; 95% CI 0.923-0.972), and E/e' ratio (OR 1.059; 95% CI 1.009-1.112). In a cohort of Chagas disease from endemic areas, impaired LV GLS was detected in a significant proportion of patients, despite normal ECG and preserved LVEF. The main determinants of reduced LV GLS were ST-T abnormalities, QRS duration, LVEF and E/e' ratio, adjusting for demographical and clinical data.