Respiratory Virus Infections in Acute Heart Failure

This study is investigating how often respiratory viruses (like flu, RSV, or COVID-19) trigger episodes of acute heart failure — and whether identifying a viral cause changes how patients are treated and how they recover. **You may be eligible if...** - You are 19 or older - You have been admitted to a cardiology ward with acute heart failure - You have elevated NT-proBNP levels (a heart stress marker above 300 pg/mL) - Your doctor suspects a possible respiratory viral infection (fever, cough, respiratory symptoms, or elevated CRP) - You have had a nasopharyngeal swab (nose/throat swab) for a respiratory virus test within 72 hours of admission **You may NOT be eligible if...** - A clear non-viral cause of your heart failure has been identified (e.g., a new heart attack, pacemaker need, or uncontrolled arrhythmia) Talk to your doctor to see if this trial is right for you.