NOS2 and hydrops fetalis: A similar direction of changes in iNOS expression/activity was observed in patients with cardiomyopathy [173,176,177,178], valvular heart disease [173], coronary artery disease [180], and ischemic heart disease [177], and this suggests that iNOS is linked to heart failure (HF) itself (also in quantitative terms, NYHA class), rather than being connected to the underlying cause of the HF.