Skeletal muscle ventricles: update after 18 months in circulation

Area of Science:

• Biomedical Engineering
• Cardiovascular Surgery
• Regenerative Medicine

Background:

• Heart failure remains a significant cause of morbidity and mortality worldwide.
• Current mechanical circulatory support devices have limitations, including infection and thromboembolism.
• Autologous skeletal muscle has been explored for cardiac reconstruction and assistance.

Purpose of the Study:

• To evaluate the long-term efficacy and safety of skeletal muscle ventricles (SMVs) as cardiac assist devices.
• To assess the performance of SMVs in both left- and right-sided circulatory support.
• To investigate the potential of SMVs for treating patients with heart failure.

Main Methods:

• Skeletal muscle ventricles (SMVs) were constructed using canine latissimus dorsi muscle.
• SMVs were connected to the aorta as aortic diastolic counterpulsators in chronic animal models.
• Performance was assessed using a mock circulation device and in vivo chronic implantation for up to 18 days.
• Thromboembolic complications were monitored throughout the study.

Main Results:

• One canine subject with an SMV has been alive and well for 18 months, demonstrating continuous function without thromboembolic complications.
• SMVs demonstrated cardiac-type work output comparable to the left ventricle in a mock circulation setting.
• In acute experiments, SMVs effectively bypassed the right side of the heart for up to 8 hours.
• Chronic right-sided circulation support with SMVs was effective for up to 18 days.

Conclusions:

• Skeletal muscle ventricles are a viable option for long-term cardiac assistance.
• SMVs show potential for treating both left- and right-sided heart failure.
• The absence of thromboembolic complications in long-term implants suggests a favorable safety profile for SMVs.