2. If EF is normal, subjects must demonstrate elevated filling pressures as evidenced by at least one of the following: a) left atrial enlargement (LAVI > 32 mL/m2); b) at least stage II diastolic dysfunction; c) Documentation of elevated NT-pro BNP levels or other natriuretic peptide marker (BNP, ANP) according to the laboratory and assay upper limit of normal in the previous year.