Left Ventricular Functions Assessment by Speckle Tracking in Comparison with The Two-Dimensional (2D) Echocardiography in Patients with Fragmented QRS

Abstract

Background and Aim: Fragmented QRS (fQRS) are electrocardiographic signals reflecting altered ventricular conduction around regions of a myocardial scar and/or ischemia. However, it could be presented in normal healthy individuals. But, its incidence and its role in prediction of cardiac disease is not yet addressed. This study aiming to assess the left ventricular (LV) functions in patients with apparent normal LV functions with fQRS using two-dimensional (2D) speckle tracking echocardiography.

Patients and Methods:  This cross-sectional study take place from March to October 2020. Fifty non cardiac patients who undergo preoperative cardiac assessment of non-cardiac surgery at cardiology department were included. All subjects are submitted to full history taking, complete general and local examinations, twelve lead ECG searching for fQRS complex and exclude ischemia and arrhythmia, and transthoracic echocardiography to assess LV functions as described previously.

Results:  36% fQRS complex was in anterior lead, 50% were in Inferior lead and only 14 % was in Lateral lead. Mean EF was 58.9 ± 5.8%, ranging from 55 to 65, FS was 26.7±1.9%, with range of 24 to 40%. LVEDD 4.5±0.7cm, LVESD was 3.3±0.4cm, Intraventricular septum was 10.1±0,6 mm and Posterior wall thickness 9.6±07 mm. Left ventricular longitudinal strain in 2 chamber apical view was 16.4±3.3%, 4 chamber apical view was 16.7±3%, apical long axis view was 17.7±3.5% and average LV GLS was 18.1±2.9%. There were 15 cases abnormal LV diastolic function according to E/e` ratio and 9 cases according to LV-GLS. There was statistically significant different between assessment of LV function by 2D echocardiography and speckle tracking.

Conclusion: The presence of fQRS on standard electrocardiography in apparently healthy people with preserved EF is associated with some sort of subclinical LV dysfunction and two-dimensional speckle tracking is more accurate and sensitive than two-dimensional echocardiography in detection of those patients.