NTproBNP levels ≥ 1000 pg/mL helped differentiate patients with a severe exacerbation of heart failure symptoms—NYHA class III and IV—with a test sensitivity of 69% and specificity of 58% (AUC = 0.66; 95% CI = 0.55–0.78; p = 0.01). The gene discussed is NPPB; the disease is heart failure.