Abstract: AIM:To observe the effects of ligustrazine on cardiac functions of rabbits with acute left heart failure (AHF). METHODS: Rabbit model with AHF was established by transfusing verapamil through vein. Different doses of ligustrazine were then injected to observe their effects on cardiac hemodynamics of rabbits with AHF. RESULTS: Both low (8.0 mg/kg) and high (16.0 mg/kg) doses of ligustrazine improved many of the hemodynamic indexes in rabbits with AHF. They significantly increased systolic blood pressure, diastolic blood pressure, pulse pressure, left ventricular systolic pressure, maximum ascending and descending velocity of left ventricular pressure (+dp/dtmax, -dp/dtmax) (n=5, P<0.05), and decreased left ventricular end-diastolic pressure (LVEDP) (n=5, P<0.05). Ligustrazine dilated vessels in a dose-dependent manner. However, no significantly different effects between low and high doses of ligustrazine on positive inotropic action were found. CONCLUSION: Ligustrazine can markedly improve many hemodynamic indexes in rabbits with AHF and is helpful for the treatment of AHF.