[A new skeletal muscle powered ventricle (SMPV) designed to work under physiologic preload]

Area of Science:

• Biomedical Engineering
• Cardiovascular Science
• Surgical Technology

Background:

• Maximizing pumping function in skeletal muscle powered ventricular prostheses (SMPV) requires high preload (over 30 mmHg).
• The influence of pump size and configuration on necessary preload remains undetermined.
• Existing SMPV designs may not be optimal for achieving desired hemodynamic performance.

Purpose of the Study:

• To compare the pumping performance of a novel double barrel dual chamber single layered (DCSL) SMPV with a single chamber double layered (SCDL) SMPV.
• To evaluate stroke volume (SV) and stroke work (SW) under physiologic conditions.
• To assess the muscle mass requirements for each pump configuration.

Main Methods:

• A new DCSL SMPV with two small pumps in parallel was designed and compared to a SCDL SMPV.
• Acutely constructed SMPVs (10 DCSL, 12 SCDL) were implanted in mongrel dogs using untrained latissimus dorsi muscle.
• Stroke volume and stroke work were measured under controlled physiologic afterload (120 mmHg) and preload (15 mmHg).

Main Results:

• The DCSL SMPV achieved a significantly larger stroke volume (9.9 +/- 1.2 ml) compared to the SCDL SMPV (6.9 +/- 0.6 ml) (p < 0.05).
• The DCSL SMPV also demonstrated significantly greater stroke work (0.84 +/- 0.15 x 10(6) ergs) than the SCDL SMPV (0.55 +/- 0.07 x 10(6) ergs).
• The DCSL pumps required less muscle mass for construction.

Conclusions:

• The DCSL SMPV design exhibits superior pumping performance, including higher stroke volume and stroke work, compared to the SCDL design.
• The DCSL configuration is more efficient, offering better performance under physiologic preload and afterload conditions.
• This novel DCSL SMPV design presents a promising advancement for ventricular assist devices, potentially requiring less muscle mass.