Patients with asymptomatic LVEF < 40%Clinical HF:- HFrEF: HF symptoms/signs and LVEF < 40%- HFmrEF: symptoms/signs of HF with elevated NT-proBNP, LVEF 40–49%, and at least one additional criteria (enlarged LA, LV hypertrophy, or other relevant diastolic function parameters)- HFpEF: in presence of symptoms/signs of HF, elevated NT-proBNP, LVEF ≥ 50%, and at least one additional criteria (enlarged LA, LV hypertrophy, or other diastolic dysfunction parameters). This evidence concerns the gene NPPB and hydrops fetalis.