Beyond the differences in mortality, patients receiving mechanical valves had a lower risk for repeat operations but had an increased risk of bleeding. (clinicalresearchforum.org)
Envisioned as a race car available from the factory, the L88 came with aluminum heads with enlarged valves, a forged cross-drilled crankshaft, a radical cam with mechanical valve lifters, a massive Holley carburetor, a lightweight Harrison cross-flow radiator, high - compression aluminum pistons, and special spark plugs and ignition wires. (corvetteblogger.com)
Mechanical valves practically last forever, but the disadvantage is that patients have to take a blood thinner to prevent blood clots. (scientificamerican.com)