This study aimed to evaluate the effects of propofol in diluted and undiluted formulations on cardiac function in infants. Infants > 30 days received propofol sedation for central line insertion. Cases were divided into two groups: those who received undiluted 1% propofol (P1%); and those who received a diluted formulation (Pd) of equal volumes propofol 1% and 0.9% NaCl. Echocardiograms were performed pre (t₀)-, immediately post (t₁)-, and 1-h post (t₂) propofol administration. Myocardial deformation was assessed with tissue Doppler imaging (TDI) analysis and peak longitudinal strain (LS). 18 cases were included: nine (50%) P1% and nine (50%) Pd. In the P1% group, TDI velocities and LS were significantly reduced at t₁ and t₂. In the Pd Group, only TDI velocities in the left ventricle were reduced at t₁, but not at t₂. Dilution of propofol may minimize myocardial dysfunction while maintaining adequate sedation in infants. Further comparative studies are needed to investigate the safety and efficacy of this approach.