Myocardial Work Index Dispersion as a Potential Predictor of Ventricular Arrhythmias in Patients with Heart Failure with Reduced Ejection Fraction

Background: Mechanical dispersion of left ventricular contraction reflects electromechanical heterogeneity and may contribute to arrhythmogenesis. We evaluated whether myocardial work dispersion is associated with ventricular arrhythmia (VA) risk in patients with heart failure with reduced ejection fraction (HFrEF). Methods: Eighty-five patients with HFrEF and no history of atrial fibrillation of any type and with complete arrhythmia follow-up (mean age 65 ± 12 years, 83.5% male, mean LVEF 30.5 ± 6.6%) underwent echocardiography one day before elective implantable cardioverter-defibrillator (ICD) or cardiac resynchronisation therapy (CRT) implantation and were followed for one year. Results: VAs—sustained or non-sustained ventricular tachycardia, or ventricular fibrillation—occurred in 32.9% of patients. Myocardial work index (MWI) dispersion, expressed as standard deviation (SD) or Range, showed the highest single-parameter discrimination (AUC 0.848 and 0.859). Models combining MWI dispersion with right atrial (RA) area performed best (AUC 0.912 and 0.911). In multivariable logistic regression, both MWI dispersion and RA area were independently associated with VAs; odds ratios per 10-unit increase were 1.116 for MWI dispersion (SD), 1.030 for MWI dispersion (Range) and 1.276 per 1 cm2 of RA area. Conclusions: In this cohort, MWI dispersion showed the highest single-parameter discrimination for VAs among the echocardiographic variables tested, and its combination with RA area gave the best model. The two variables were independently associated with VAs in the same model. These exploratory findings are hypothesis-generating and require external validation before clinical application.