Feasibility and outcomes of an automated high-alert NT-proBNP pathway

NT-proBNP is a key biomarker in heart failure (HF). Patients with markedly elevated levels are at high risk of adverse outcomes but experience delays in specialist care. Evidence on the impact of an automated, high-threshold NT-proBNP referral pathway embedded in electronic patient records is limited.

All NT-proBNP results >5000 pg/mL over a 12-month period triggered automatic HF team referral. Referrals were categorised as inpatients, outpatients with known HF, outpatients not suitable for follow-up or new outpatients without a diagnosis of HF who were eligible for enrolment. Eligible patients were offered echocardiography and review within 48 hours, with treatment and outcome data collected prospectively. A retrospective comparator cohort included all outpatient NT-proBNP results >5000 pg/mL from patients not known to the HF service in the 12 months before implementation.

Over 12 months, 889 referrals were generated: 417 (47%) inpatients, 370 (42%) known outpatients, 59 (7%) not appropriate and 43 (5%) enrolled. Median time to review was 2 days, with 70% meeting the 48-hour target. Among enrolled patients (mean age 81, 56% male, median NT-proBNP 7480 pg/mL), HF with reduced ejection fraction (HFrEF) was diagnosed in 21 (49%), HF with mildly reduced ejection fraction in seven (16%), HF with preserved ejection fraction in 10 (23%) and severe aortic stenosis or new atrial fibrillation in four each (10%). At 12 weeks, 62% of patients had improved by at least one New York Heart Association class, and mean left ventricular ejection fraction increased from 27% to 45% in those with HFrEF. At 12 weeks, admission and mortality were 36% and 8%, respectively, compared with 35% and 12% in the retrospective cohort (n=60).

An automated high-threshold NT-proBNP pathway is feasible and identifies very high-risk patients. Enrolled patients had rapid therapy optimisation, with observed improvements in symptoms and cardiac function.