Table 1. Major differences in HF definition, classification and HF-PEF diagnosis between the ESC and ACCF/AHA Guidelines.

	2012 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure	2013 ACCF/AHA Guideline for the management of heart failure
HF definition	Abnormality of cardiac structure or function leading to failure of the heart to deliver oxygen at a rate commensurate with the requirements of the metabolizing tissues, despite normal filling pressures (or only at the expense of increased filling pressures).	Complex clinical syndrome that results from any structural or functional imparment of ventricular filling or ejection of blood.
HF classification	HF-REF  Symptoms  Signs  Reduced LVEF (LVEF < 45%) HF-PEF  Symptoms  Signs  Normal or mildly reduced LVEF and LV not dilated  Relevant structural and/or functional heart disease	Stage A  At high risk for HF but without structural heart disease or symptoms Stage B  Structural heart disease but without signs or symptoms Stage C  Structural heart disease with prior or current symptoms of HF   HF-REF (LVEF ≤ 40%)   HF-PEF Stage D  Refractory HF
HF-PEF diagnosis	Requires 4 conditions to be satisfied  Typical symptoms of HF  Typical signs of HF  Preserved LVEF and LV not dilated   EF ≥ 45%   LVEDVi < 97 mL/m2   LVEDDi < 29 mm2 Relevant structural heart disease and/or diastolic dysfunction   LAVi > 34 mL/m2   LVMi > 115 g/m2 (M)   LVMi > 95 g/m2 (F)   E/E' ≥ 8   E' average < 9 cm/s	Stage C HF  Known structural heart disease  Typical Signs and Symptoms  Preserved LVEF   a. LVEF ≥ 50%    HF-PEF   b. LVEF 41-50%    Borderline HF-PEF

F: female; HF-REF: heart failure with preserved ejection fraction; LAVi: left atrial volume indexed; LVEDDi: left ventricular end diastolic diameter indexed; LVEDVi: left ventricular end diastolic volume indexed; LVEF: left ventricular ejection fraction; LVMi: left ventricular mass indexed; M: male.