Background . The effect of stent size and number on left ventricular systolic function improvement after percutaneous coronary intervention (PCI) using drug eluting stent is not clear enough. Aim . To study short-term effect of stent size and number on left ventricular systolic function improvement after elective PCI. Material and methods . The study included 150 adult patients with electively stented left anterior descending artery lesion with drug-eluting stent. Patients were examined before PCI and 1 and 3 months after PCI using speckle tracking echocardiography. Results . Before revascularization, mean left ventricular ejection fraction was 51.2%±5.7, mean global longitudinal peak systolic strain (GLPSS) --9.29±0.94%. One month after PCI, mean GLPSS improved significantly to -14.05±1.72% (p<0.001), 3 months after PCI, even more significant improvement in the GLPSS up to -18.61±3.02% (p<0.001) was recorded. After 3 months, 53 patients (35.3%) showed recovery to normal GLPSS. The predictors of non-improvement of GLPSS after 3 months were: diabetes mellitus (p=0.007), smoking (p=0.01), dyslipidemia (p=0.001), stent length (p=0.001), and a number of stents (p=0.04). There was strong negative correlation between stent length and improvement of the GLPSS in 1 month (p=0.007) and in 3 months (p<0.001). Also there was strong negative correlation between number of stents and improvement in 1 month (p=0.002) and in 3 months (p=0.004), but the correlation between stent diameter and improvement of the GLPSS was significant neither in 1 month nor in 3 months (p=0.924 and p=0.435, respectively). Conclusion . Number and length of stents implanted were predictors to improvement of systolic function, while stent diameter doesn't affect left ventricular recovery.