Many die yearly of heart failure despite present treatment. A frequently suggested treatment innovation uses multiple conditioned and paced skeletal muscles, linked to drive already-proven mechanical support devices.
But adequately durable muscle-prosthetic bonding has never succeeded. Tissue simply cannot long tolerate pressures generated—up to 40,000 mmHg—at the tissue/prosthetic interface when needed forces (100 or more Newtons) are borne by sutures or clamps.
Dramatically increasing force-transfer surface, by dispersing ultrafine polymer fibers distally in muscle, may solve this. A device was conceived, developed and tested by the student. This dissertation comprises mathematical exploration, three sequential experimental studies confirming results and mechanism, and a US patent.
An Introduction presents the significance of the problem: the human and economic need for effective mechanical heart failure treatment, the lack of a safe and effective power supply, and the pivotal role a successful muscle-to-prosthetic coupling could play in a solution.
Then, computational and initial experimental examinations are Chapter 1, published in a peer-reviewed journal. Pull-out strength in a pilot 30 day rabbit test was nine times that needed.
Other investigators, at a separate institution with a canine Iatissimus model, collaborated with the student in confirmatory work, with strength again far exceeding need. This (Chapter 2) is also a peer-reviewed publication.
In the final experiments described (Chapter 3), the postulated tissue integration of the fibers was explored using the rabbit posterior tibial model in more animals for longer times (up to 90 days), with contralateral buttressed-suture controls. More-thanadequate bond-strength was shown stable over this longer period. Histologically, there was indeed thorough integration: over 85% of sampled surface points were adjacent solid tissue structures. The hypothesis—that this type achieves its strong durable bond by thorough tissue integration—was shown true.
The student has patented the device (US 6,214,047,10 April, 2001). The patent is included as Chapter 4.
The application of this technology for the original intent of mechanical circulatory support power and also for unmet orthopaedic applications requiring muscle-to-prosthesis fixation continues.