An electrical subsystem to enable valve operation and to power navigation aids or other equipment.

In 1995 he conducted another pioneering operation: he performed the first Heartport procedure, using a device that allows minimally invasive coronary bypass and valve operations.

The valve operation is independent of the spin speed or the location of the valves and therefore allows for more complex biological assays integrated on the disk.

Later L engines (3L and 5L) also use this method of valve operation.

Once more fully developed, electronic valve operation will yield even more benefits.

With electronic valve operation, it will be possible to control engine speed by regulating valve lift.

This allows continual adjustment of valve operation, according to the needs of the engine at different speeds.

The valve operation is the same in each case.

These 4 patients were re-operated upon at between one week and 50 months following the first valve operation.

A valve operation can cost $40,000 to $50,000 and require a hospital stay of a week or more.