Cardiac myosin-binding protein C in community-based patients with suspected heart failure.

INTRODUCTION

Myocardial injury is a hallmark of heart failure (HF). It is unknown whether established (e.g. troponin) or novel biomarkers of myocardial injury [e.g. cardiac myosin-binding protein C (cMyBP-C)] provide additive diagnostic value beyond natriuretic peptides in community patients with suspected HF.

METHODS

Community-based patients with suspected HF and elevated NT-proBNP levels were recruited into a multicentre, prospective, observational study at five sites (NCT04724200). Venous blood sampling was performed at the time of echocardiography. HF was classified according to left ventricular ejection fraction: HF with reduced ejection fraction (HFrEF) = ≤40%, HF with mildly reduced ejection (HFmrEF) = 41-49%, and HF with preserved ejection fraction (HFpEF) = ≥50% with HFA-PEFF score ≥5. NT-proBNP (Roche Elecsys® assay), high-sensitivity cardiac troponin T (hs-cTnT, Roche Elecsys® assay) and cMyBP-C (Roche precommercial assay) were measured. Diagnostic accuracy of each biomarker alone and in combination was examined using the area under the receiver operating characteristic curve (AUROC).

RESULTS

Of 867 patients, 751 (87%) had measurable left ventricular ejection fraction and available biomarker data. Of these, 43 (6%) had HFrEF, 75 (10%) HFmrEF, and 278 (37%) HFpEF. NT-proBNP levels were highest in patients with HFrEF, with similar patterns observed for hsTnT and cMyBP-C. For the diagnosis of HF versus no HF, the combination of NT-proBNP and cMyBP-C had the highest AUROC of 0.77 (95%CI 0.73-0.80) versus NT-proBNP alone [0.74 (0.71-0.78); P = .003]. For detection of HFrEF versus no HF, the AUROC was 0.90 (0.86-0.95) for the combination of NT-proBNP and cMyBP-C compared with 0.85 (0.80-0.90) for NT-proBNP alone (P = .006).

CONCLUSION

Measurement of cMyBP-C improved the diagnostic accuracy of NT-proBNP in community-based patients with suspected HF, with greatest additive value for identifying HFrEF, and may help in the prioritization of echocardiography.