Iloprost improves ventricular function in the hypertrophic and functionally impaired right heart by direct...

Area of Science:

• Cardiology
• Pharmacology
• Physiology

Background:

• Right heart dysfunction is critical in pulmonary arterial hypertension and congenital heart disease.
• Prostacyclin analogs are used to treat pulmonary hypertension, but their direct effects on the right ventricle are unclear.

Purpose of the Study:

• To determine if iloprost has a direct inotropic effect on the pressure-overloaded, hypertrophic, and dysfunctional right ventricle (RV).

Main Methods:

• Rats underwent monocrotaline injection or pulmonary trunk banding to induce RV pressure overload.
• RV function was assessed using MRI, echocardiography, and invasive pressure measurements.
• Iloprost was administered intravenously at different doses, and effects were compared to placebo and nitroprusside.

Main Results:

• Iloprost significantly increased stroke volume and RV ejection fraction in both sham and pulmonary trunk banding groups.
• Cardiac output and RV systolic pressure also increased in the pulmonary trunk banding group.
• Iloprost decreased mean arterial blood pressure, but this effect alone did not improve RV function.

Conclusions:

• Iloprost demonstrates direct inotropic properties, enhancing ventricular function in the hypertrophic and dysfunctional rat right heart.
• These findings suggest a potential therapeutic role for iloprost in managing right heart failure associated with pulmonary hypertension.