Definition
The pericardial sac, also known as the pericardium, is a double-layered sac that surrounds the heart. Think of it as the heart's personal bodyguard, protecting it from friction and infection. It’s not directly attached to the heart; there’s a space between the layers filled with fluid. This fluid acts as a lubricant, allowing the heart to beat smoothly. The sac provides physical support and prevents overexpansion. It’s like a cozy, protective bubble wrap for your heart. ❤️