ABSTRACT
Objective To explore the characteristics of the flow velocity waveform of superior vena cana (SVC) in a rat model with chronic monocrotaline-induced pulmonary hypertension by echocardiography.Methods The chronic pulmonary hypertension model was developed by monocrotaline solution (60 mg/kg) injection into the abdominal cavity in 32 SD rats.Eight rats with the placebo injected served as controls.An examination of the flow velocity waveform of SVC was performed by Doppler echocardiography via supraclavicular fossa before and 28-day after the injection.The pulmonary arterial systolic pressure was measured by pressure-guided micro-catheter 28-day after the injection both in the control and the pulmonary hypertension model group.Results Chronic monocrotaline-induced pulmonary hypertension was successfully developed in 29 rats.The flow velocity waveform of SVC showed that the ratio of the maximum reverse peak flow velocity due to atrial contraction (VAR) to the maximum systolic peak flow velocity (Vs) and VAR increased dramatically 28-day after the monocrotaline solution injection in both sides of SVC (P ＜0.01), while only the Vs of the right SVC significantly decreased (P ＜0.05).Conclusions The changes of VAR/Vs ratio and VAR in rat model with chronic monocrotaline-induced pulmonary hypertension suggested that the changes of flow velocity waveform of SVC have indicating features in reflecting pulmonary hypertension.