Is it true? Weightlifters never do cardio?

I've been doing a great deal of research and this is one of the gems I've come across.  Apparently, professioonal weightlifters never do cardio because it prevents the development of lean muscle.

I also read that cardio reduces the size of your heart. The heart is not meant for sustained running, jogging etc. Because the requirements of cardio demands that the heart provide a steady stream of oxygen it adapts, by shrinking, to meet that need. It also means that it can't meet any extra exertion which is why athletes drop dead from heart attacks when they've ended their routine. The heart is too small and inadequate to recover.

There's more and there's a similar story with the lungs. I'm not sure if I've described it correctly but it all sounds logical and sensible to me.