Abstract
A new bioprosthetic cardiac valve cross-linked with glycerol polyglycidyl ether (polyepoxy compound=PC) was developed. It was evaluated in animal studies. Aortic valves harvested from mongrel dogs were treated with PC (PC valve). RV-PA bypasses were made in 7 dogs with a conduit composed of a PC valve and two vascular grafts attached to the inflow and outflow sides of the valve (PC-valved conduit). The main PA was ligated. The pressure gradient across the PC valve was 5mmHg and the diastolic pressure of the PA was 19mmHg, which indicated almost no stenosis nor regurgitation of the PC valve. RVG performed at 36 days (1 dog) and 37 days (1 dog) showed the PC valve in good function and no visible thrombus in the valve. Biologic materials cross-linked with PC increase in strength as do those cross-linked with glutaraldehyde (GA). While biologic materials cross-linked with GA become yellowish, hard and hydrophobic, those cross-linked with PC maintain their original white color and pliability, and become hydrophilic and hydrated. The hydrophilicity and hydration, compared with hydrophobicity and less hydration, provide sufficient antithrombogenicity and better characteristics for infiltration and diffusion of water which includes nutrition, oxygen and electrolytes, etc., leading to inhibition of material degeneration. As the PC-treated vascular graft is reported to have shown no calcification in long-term results, the PC-treated bioprosthetic cardiac valve should also not calcify with long-term use. Therefore, the PC valve displays good valve function and sufficient antithrombogenicity and is expected to have excellent durability without calcification or degeneration.
