Post-bypass pericardial effusion: What should I expect?

Hey everyone, looking for some insight or advice here:

My mom had a quadruple bypass on October 1st. Since then, things have been messy—fluid buildup in her pericardium and lungs, plus some clotting in the pericardial sac. Doctors drained the fluid from her heart and lungs surgically, but they left the clot alone because reopening her chest was too risky.
How bad is this clot situation? Is there a chance it just dissolves on its own or through meds, and what kind of complications should I be watching out for (any specific symptoms)?

Thanks in advance
Mark White3

The most critical part was getting that fluid drained; they had to relieve the pressure on the heart and lungs immediately. As for the clot, if it isn't massive, it shouldn't pose a major threat within the pericardium—it’ll likely just break down on its own over time.