NPPB and hydrops fetalis: Elevated levels of both BNP and NT-proBNP have been reported in patients with a variety of cardiac and noncardiac causes, including advancing age, anemia, renal failure, obstructive sleep apnea, severe pneumonia, pulmonary embolism, pulmonary arterial hypertension, critical illness, bacterial sepsis, and COVID-19 infection.22–26 Michelle reported that plasma BNP levels were a stronger risk factor than traditional risk factors in patients without HF.