NPPB and obesity due to melanocortin 4 receptor deficiency: Heart failure (HF) remains a high-burden syndrome in which natriuretic peptides (BNP/NT-proBNP) are foundational for diagnosis and risk stratification, yet their interpretation is frequently confounded by comorbidities—most notably obesity, atrial fibrillation, and chronic kidney disease—highlighting the need for complementary, pathophysiology-anchored biomarkers (1).