Abstract Funding Acknowledgements Type of funding sources: None. Introduction Mitral valve prolapse (MVP) could associate with malignant ventricular arrhythmias. Mitral annular disjunction (MAD), which leads to excessive mobility, mechanical stretch, and myocardial damage, has been studied as a putative mechanism for an arrhythmic substrate. However, it is unclear whether that is the only sufficient arrhythmic risk factor in that patients. The aim of our study was to check whether two–dimensional speckle tracking echocardiography (STE) with segmental longitudinal strain and STE-derived myocardial work (MW) analysis may allow for a more accurate assessment of the arrhythmic risk in MVP patients. Methods and results Seventy-two MVP patients and twenty healthy volunteers enrolled in the study had performed echocardiography with STE assessment. Non-sustained ventricular tachycardia (NSVT) was the arrhythmic outcome for further calculations. Pre-specified cut-off values for peak segmental longitudinal strain (PSS) and segmental myocardial work index (MWI) for basal lateral (−25% and 2200 mmHg%), mid-lateral (−25% and 2500 mmHg%), mid posterior (−25% and 2400 mmHg%), and mid inferior (−23% and 2400 mmHg%) segments were accurate predictors of NSVT. A combination of PSS and MWI increased the probability of NSVT occurrence, reaching the highest predictive value for the basal lateral segment (Figure): odds ratio 32.15 (3.78–273.8), p < 0.001 for PSS ≥ (−25%) and MWI ≥ 2200 mmHg%. Conclusions 2D STE may be a valuable tool for assessing arrhythmic risk in MVP patients. Excessively increased segmental longitudinal strain with augmented regional myocardial work index identifies patients with the highest risk of NSVT.