Utilizing natriuretic peptides to identify high-risk patients in the diagnostic gray zone of patients with suspected acute myocardial infarction

Abstract

Many patients presenting with suspected acute myocardial infarction (MI) are at high cardiovascular (CV) risk, even if MI is ruled-out. Heart failure (HF) is a frequent cause of CV morbidity and mortality, however, many remain underserved despite available therapies. To investigate the utility of systematic versus clinically-driven evaluation of N-terminal pro-hormon of natriuretic peptide (NTproBNP) to identify individuals at increased HF risk in patients with suspected MI. Patients with suspected MI were prospectively enrolled in an observational cohort study at a tertiary medical center in Germany. Clinical management, laboratory (e.g., natiuretic peptides [NTproBNPclinical]) or imaging testing beyond high-sensitivity cardiac troponin (hs-cTn) was at the treating physician’s discretion. Additionally, NTproBNP was systematically measured in all 0-hour biobank samples (NTproBNPbiobank). Patients were triaged using the ESC 0/1-hour algorithm with hs-cTnI and categorized into rule-out, observe or rule-in. Recommended NTproBNP cut-offs were applied for chronic (<75 years: ≥125pg/mL; ≥75 years: ≥450pg/mL) and acute (<50 years: ≥450pg/mL; 50-75 years: ≥900pg/mL; ≥75 years: ≥1800pg/mL) HF. All-cause death was assessed through 5 years. Among 3,075 patients the median age was 63 (IQR 51, 75) years, 1,088 (35.4%) were female, 524 (17.0%) had a final diagnosis of MI, and 332 (10.8%) a history of HF. Using NTproBNPbiobank, 1,654 (53.8%) patients met cut-offs for chronic HF and 650 (21.1%) for acute HF. In these, prior HF was known in 288 (17.4%) and 189 (29.1%) patients, respectively. NTproBNPclinical was not ordered in 1,937 (63.0%) patients; in these NTproBNPbiobank identified 913 and 289 patients (29.7% and 9.4% of the overall study population) exceeding chronic and acute HF cut-offs, respectively (Fig. A). Survival was significantly reduced in patients exceeding NTproBNP cut-offs for chronic HF, irrespective of whether NTproBNP was ordered clinically or not (p<0.001; Fig. B). Probability of meeting NTproBNP HF cut-offs was significantly associated with hs-cTnI (restricted cubic spline overall effect p<0.001). Proportions of patents meeting chronic and acute HF cut-offs increased significantly in ESC 0/1-hour groups from rule-out to rule-in group (Fig. A; p<0.001 for both). Among observe-group patients without prior HF or NTproBNPclinical determination, systematic NTproBNP evaluation identified additional 321 (38.8%) and 106 (12.8%) patients meeting chronic and acute HF NTproBNP cut-offs, respectively. In patients with suspected MI, clinically driven evaluation of NTproBNP occurred in 37%, however, substantially more patients met criteria for chronic or acute HF. Broader utilisation of NTproBNP may identify more patients at increased risk for death that benefit from contemporary HF therapies. Particularly the observe group may represent an appropriate target for such a strategy.Figure AFigure B