Complement factor 1 inhibitor improves cardiopulmonary function in neonatal cardiopulmonary bypass

Area of Science:

• Cardiovascular Surgery
• Neonatal Medicine
• Immunology

Background:

• Cardiopulmonary bypass (CPB) in neonates with congenital heart defects causes inflammatory injury.
• Complement and contact activation pathways mediate this CPB-induced injury.
• Complement factor 1 esterase inhibitor (C1-inh) may be depleted during CPB.

Purpose of the Study:

• To test if C1-inh supplementation can reduce cardiac and pulmonary dysfunction in neonatal CPB.
• To evaluate the dose-dependent effects of C1-inh on CPB-related injury.

Main Methods:

• Fifty-two neonatal pigs received varying doses of C1-inh (0, 500, 1000, 1500 IU) before 90 minutes of normothermic CPB.
• Pulmonary and cardiovascular parameters were measured pre- and post-CPB.
• C1-inh levels, weight gain, lung compliance, and cardiac pressures were analyzed.

Main Results:

• C1-inh levels increased with dose post-CPB.
• Pulmonary dynamic compliance and alveolar-arterial O2 gradient improved with C1-inh.
• Systolic cardiac function (dP/dt(max)) improved, but diastolic function (time constant of relaxation) was impaired at the highest dose.

Conclusions:

• C1-inh supplementation enhances pulmonary and systolic cardiac function during neonatal CPB.
• The observed negative impact on diastolic function necessitates further investigation.
• C1-inh shows potential therapeutic benefits for neonatal CPB, with dose-dependent effects.