HK2 and atrial fibrillation: Analysis revealed significant upregulation of key glycolytic enzymes including hexokinase 2 (HK2), glucose transporter 1 (GLUT1), phosphofructokinase muscle type (PFKM), pyruvate kinase M2 (PKM2), and lactate dehydrogenase A (LDHA), along with elevated lactate accumulation in atrial tissues of AF patients compared to sinus rhythm controls (Figure 1C,D).