Video cables are different from speaker wires. First off, they are coaxial cable, which means one wire inside a "shield" surrounding it, to prevent noise pickup. Likewise, they are what' called "75 ohm impedance", which assures that the maximum signal reaches it's destination. All video products are designed to work best with 75 ohm cable.

Speaker wire is neither of the above. It's generally two unshielded parallel wires in one jacket of undetermined impedance.

Of course, you could always kludge some RCA connectors on the ends of what's otherwise a fine speaker cable, but it still won't be a good video interconnect.