Yes, over filled, in trauma it’s always Blood.
The sac contains its own fluid.
A torn cardiac blood vessel (like from a blow to the chest) will leak into the sac, filling that sac more than the fluid, and to the point of emergency surgery to relieve the buildup. If the vessel is bleeding heavily into the sac, Cardiac Tamponade occurs.
Death will soon follow.
I post Cleveland Clinic (The World’s Finest Cardiac Hospital) and you quote one line from Wikipedia……..oooooook.
One thing I’ll say about you vaccine obsessed folks, you sure can’t admit when you’re wrong or admit people even died before the Covid vaccine.
Over on Twitter there’s a Tard Nugget that thinks MyoCarditis is a new condition that never existed before the Covid vax.