The role of global longitudinal strain and mechanical dispersion in assessing the severity of ventricular arrhythmia in patients with ischemic heart disease after left ventricular myocardial infarctio

Abstract Introduction Ventricular arrhythmias(VA) are a major cause of morbidity and mortality in patients with ischemic heart disease, especially after myocardial infarction. Traditional echocardiographic parameters, such as left ventricular ejection fraction, often fail to fully capture the risk of arrhythmogenic events. Advanced imaging techniques like two-dimensional speckle-tracking echocardiography provide additional insights by assessing myocardial deformation and contraction heterogeneity. Objective To evaluate the role of global longitudinal strain (GLS) and mechanical dispersion (MD) in predicting the severity of ventricular arrhythmia in patients with ischemic heart disease (IHD) following left ventricular myocardial infarction, using two-dimensional speckle-tracking echocardiography. Methods The study included 127 patients with IHD and post-infarction cardiosclerosis (confirmed Q-wave myocardial infarction on ECG). All patients underwent physical examination, laboratory testing, 12-lead ECG, 24-hour Holter monitoring, transthoracic echocardiography and coronary angiography. The average age was 61.6 ± 9.7 years. Based on the presence and severity of VA, patients were divided into four groups: Group 1: 44 patients without VA Group 2: 29 patients with VA of class I–II Group 3: 24 patients with VA of class III Group 4: 30 patients with VA of class IV–V (Classification according to B. Lown and M. Wolf) Results Among the 127 patients studied, no statistically significant differences were observed in left ventricular ejection fraction (LVEF) across the four groups (P = 0.835), with values ranging from 44.21% to 46.52%. Similarly, global longitudinal strain showed no significant variation between groups (P = 0.303), although a non-significant trend toward reduced strain was noted in patients with more severe ventricular arrhythmias. In contrast, mechanical dispersion increased progressively and significantly with arrhythmia severity: median values were 6.6 ms [IQR 5.1–13.9] in patients without arrhythmia, 16.7 ms [6.1–22.0] in class I–II, 33.4 ms [29.9–36.6] in class III, and 47.3 ms [41.5–58.5] in class IV–V (P = 0.001). These findings indicate that MD is closely associated with the severity of ventricular arrhythmias, whereas LVEF and GLS do not effectively differentiate between arrhythmic risk levels in this patient population. Conclusion Although there were no statistically significant differences in ejection fraction or global longitudinal strain among the groups, mechanical dispersion increased significantly with the severity of ventricular arrhythmias. This suggests that mechanical dispersion is an independent predictor of arrhythmia severity in patients with ischemic heart disease and post-infarction cardiosclerosis.

Hali tarjima qilinmagan