The rhBNP has similar bioactive traits as BNP that influence favorable cardiac effects such as; natriuresis, diuresis, and vasodilation.[6] The rhBNP also inhibits the renin–angiotensin–aldosterone system.[7] Several studies reported that rhBNP has positive therapeutic effects on patients with HF however, it has some side effects such as; decreasing the cardiac preload and afterload with an increase of cardiac output (CO).[8–10] The effect of rhBNP on the systemic venous circulation and its regulation on the CO have not been explored. The gene discussed is NPPB; the disease is hydrops fetalis.