Exposing Subclinical Cardiac Dysfunction in Shift Workers Using Speckle Tracking Echocardiography

Abstract

Objective: To assess subclinical myocardial disorders in shift workers using Speckle tracking echocardiography, compare shift workers and day employees' left ventricular global longitudinal strain and right ventricular free wall longitudinal strain and investigate the relationship between myocardial stress and sleep quality.

Study Design: Cross-sectional study
Place and Duration of Study: This study was conducted at the Department of Physiology, Faculty of Medicine, University of Kufa from 1st October 2024 to 28th February 2025.

Methods: A total of 120 healthy adults were recruited for this cross-sectional study, 60 of whom were shift workers (including those who work nights) and 60 of whom were day workers, matched for age and sex. Every subject received a thorough echocardiographic evaluation, which included Speckle tracking echocardiography to assess the right ventricular free wall longitudinal strain and left ventricular global longitudinal strain. Standard echocardiographic measurements and surveys on work schedules and sleep quality were safeguarded by further
tests.

Results: The left ventricular global longitudinal strain was significantly lower for shift workers (-18.4±2.3%) than for day workers (-20.3±1.5%, p < 0.001). One Likewise, shift workers had a decline in right ventricular free wall longitudinal strain (-22.1±2.7%) compared to day workers (-24.5±2.4%, p <0.001).The ejection fraction and chamber diameters, two common echocardiographic metrics, did not differ significantly between study groups. In shift workers, poor sleep was most closely associated with lower strain levels.

Conclusion: Even in the absence of overt cardiac illness, shift workers are linked to subclinical myocardial impairment that can be identified by Speckle Tracking Echocardiography. These results highlight the importance of early cardiac monitoring for shift workers in order to impose preventive measures.