NPPB and hydrops fetalis: It seems reasonable to screen patients with non-increased left ventricular wall thickness heart failure with preserved ejection fraction (HFpEF) for CA, especially if other causes of HF and elevated BNP levels (severe renal failure, fluid retention, severe anemia, clinically significant bradycardia or tachycardia, or arterial-venous shunts) can be excluded (10, 11).