<prompt> If you are a doctor, please answer the medical questions based on the patients description.Doctor, Ive been experiencing some muscle swelling, frequent urination, and I even noticed pus in my urine. On top of that, Ive been having an irregular heartbeat. What could be causing these symptoms?  <response>: Based on your symptoms, its possible that you have premature atrial contractions PACs. This occurs when the upper chambers of the heart contract earlier than they should. It can lead to an irregular heartbeat and other symptoms like youre experiencing. Well need to run some tests to confirm the diagnosis. 