{
  "abstract": "Introduction N-terminal pro-B-type natriuretic peptide (NT-proBNP) is recommended for ruling out heart failure (HF), yet very high concentrations are often assumed as diagnostic of HF despite limited evidence. The European Society of Cardiology (ESC) suggests a cut-off below which HF is unlikely of NT-proBNP of 120 pg/mL in non-acute patients and 300 pg/mL for patients presenting with acute illness. The National Institute for Health and Care Excellence (NICE) guidelines suggest a cut-off of 300 pg/mL for patients presenting acutely. NT-proBNP is often significantly elevated in noncardiac illness, especially in acutely unwell patients. We aimed to investigate diagnoses and outcomes associated with extremely high NT-proBNP values in an unselected cohort of hospitalised patients.Methods We conducted a retrospective cohort study of adult hospital admissions at a single UK centre between January 2022 and December 2023 with an NT-proBNP ≥20,000 pg/mL. Electronic clinical records were reviewed to determine diagnosis, investigations, treatments, and outcomes. Survivors and non-survivors at 6 months were compared, and multivariable Cox proportional hazard modelling was used to identify independent predictors of mortality. Variables were chosen based on their hypothesised association with mortality (age, NT-proBNP, CRP, WCC, creatinine, albumin, haemoglobin) and/or signals of significance in univariable analysis (incident RRT, CKD, hypertension). Kaplan-Meier curves were used to illustrate mortality for patients with infection versus any other cause.Results A total of 415 admissions from 412 patients were included (median age 82 years; 51.6% male). Median NT-proBNP level was 35,000 pg/mL (26,563–35,000). Commonest imaging findings were pulmonary congestion (55.4%) and infection (53.7%). Infection was the most frequent diagnosis (73.5%), including pneumonia (52.3%) and sepsis (36.6%). HF was documented in 49.2% of patients but the main diagnosis in only 19%. Overall mortality was high (43.6% in-hospital; 64.5% at 6 months), with infection as the leading cause of death. Those dying by 6 months were older, frailer, had higher NT-proBNP and inflammatory markers, and lower albumin. Among those that underwent echocardiography (72.5%), left ventricular ejection fraction was not associated with survival. In multivariable analysis, older age and lower serum albumin were independent predictors of mortality.Conclusion Amongst unselected hospitalised patients, NT-proBNP ≥20,000 pg/mL is most frequently associated with severe noncardiac illness, particularly infection, and carries very high mortality. Extremely high NT-proBNP values lack specificity for HF and should prompt immediate search for infection and sepsis rather than trigger empiric HF treatment alone. NT-proBNP should not be interpreted in isolation when assessing acutely unwell patients.Abstract 165 Table 1Baseline characteristics and laboratory valuesTotaln = 415Alive at 6 monthsn = 149Dead at 6 monthsn = 266P valueAgeyears, median (20th – 75th centile)82 (73–88)80 (70–87)84 (75–89)<0.01Malen (%)214 (51.6%)72 (48.3%)142 (53.4%)0.36NT-proBNPpg/mL, median (20th – 75th centile)35000 (26563–35000)33194 (24972–35000)35000 (27474–35000)0.02CRPmg/L, median (20th – 75th centile)102 (33.5–162)73 (22–144)127.5 (67–188)<0.01WCC×103/μl, median (20th – 75th centile)11.2 (7.9–15.6)9.5 (7.1–13.2)12.6 (8.7–17)<0.01Creatininemg/dL, median (20th – 75th centile)164 (114–240.5)158 (108–234)171.5 (117–244.8)0.57Haemoglobing/L, median (20th – 75th centile)103 (91.0–116.5)104 (92–116)103 (89.2–116.8)0.59Albuming/L, median (20th – 75th centile)27 (23.2–31)29 (20–32)26 (22–30)<0.01Lactate [n=267]mmol/L, median (20th – 75th centile)1.8 (1.2–3)1.5 (1.1–2.2)2 (1.3–3.5)<0.01P values <0.05 are highlighted in italic.NT-proBNP = N-terminal pro-B-type natriuretic peptide. CRP = C-reactive protein. WCC = white cell count.Abstract 165 Figure 1Distribution of main diagnoses among patients with NT-proBNP ≥20,000 pg/mLAbstract 165 Table 2Imaging and echocardiogram findingsTotaln = 415Alive at 6 monthsn = 149Dead at 6 monthsn = 266P valueUnderwent X-ray/CT413 (99.5%)149 (100%)264 (97.4%)0.54Pulmonary congestion231/413 (55.9%)80/149 (53.7%)151/264 (57.2%)0.61Infection224/413 (54.2%)74/149 (49.7%)150/264 (56.8%)0.22Cancer13/413 (3.1%)5/149 (3.4%)8/264 (3%)1.0Underwent echocardiogram301 (72.5%)133 (89.3%)168 (63.2%)<0.01LVEF <40%154/301 (51.2%)71/133 (53.4%)83/168 (49.4%)0.56LVEF 40-50%41/301 (13.6%)17/133 (12.8%)24/168 (14.3%)0.62LVEF >50%106/301 (35.2%)45/133 (33.8%)61/168 (36.3%)0.72P values <0.05 are highlighted in bold.CT = computed tomography. US = ultrasound. LVEF = left ventricular ejection fraction.Abstract 165 Figure 2Kaplan-meier survival curves for patients with infection versus patients with any other diagnosis",
  "authors": [
    {
      "affiliations": [
        "Hull University Teaching Hospitals NHS Trust, Hull, United Kingdom"
      ],
      "name": "Amro Abu Suleiman"
    },
    {
      "affiliations": [
        "Hull University Teaching Hospitals NHS Trust, Hull, United Kingdom"
      ],
      "name": "Christian Mitchell"
    },
    {
      "affiliations": [
        "Hull University Teaching Hospitals NHS Trust, Hull, United Kingdom"
      ],
      "name": "Ali Bhatty"
    },
    {
      "affiliations": [
        "Hull University Teaching Hospitals NHS Trust, Hull, United Kingdom",
        "University of Hull, Hull York Medical School, Hull, United Kingdom"
      ],
      "name": "Robert Desborough"
    },
    {
      "affiliations": [
        "Hull University Teaching Hospitals NHS Trust, Hull, United Kingdom",
        "University of Hull, Hull York Medical School, Hull, United Kingdom"
      ],
      "name": "Andrew Clark"
    }
  ],
  "title": "165 Extremely high nt-probnp levels in unselected hospital admissions",
  "uid": "145e5abc-5955-54e8-b5bf-fe34c8fc30f5"
}