NPPB and atrial fibrillation: MORCOR‐TURK National Registry Study: In Turkish coronary care units, newly diagnosed atrial fibrillation, compared with pre‐existing AF, is associated with a higher inflammatory burden (CRP 28.4 vs. 12.6 mg/L), elevated NT‐proBNP levels, and approximately double the in‐hospital mortality (12.0% vs. 6.8%).