Magnus Nakrem Lyngbakken, Peter Selmer Rønningen and coworkers investigated the value of echocardiographic left atrial volumes and cardiac biomarkers for prediction of incident atrial fibrillation.
Volumetric indices of the left atrium, established biomarkers (NT-proBNP and cardiac troponin T), and a novel biomarker (GDF-15) were assessed in 3487 subjects in the population-based Akershus Cardiac Examination 1950 Study. Out of these, 157 had prevalent atrial fibrillation and were not included in the analyses of atrial fibrillation risk. During follow-up of median 6.3 years, 123 (3.7%) was diagnosed with incident atrial fibrillation. In a Cox regression model, left atrial volumetric indices, NT-proBNP and troponin T were associated with risk of incident atrial fibrillation. All associations were independent of the CHARGE-AF risk score. After further adjustment for sex, troponin T was non-significant, whereas NT-proBNP and left atrial volumetric indices remained significant predictors of incident atrial fibrillation. GDF-15 exhibited no association with atrial fibrillation risk.
C statistics were 0.65 (95 CI: 0.60 to 0.69) for maximum left atrial indexed volume, 0.63 (95% CI 0.58 to 0.69) for minimum left atrial indexed volume, and 0.58 (0.52 to 0.63) for left atrial emptying fraction. Cardiac biomarkers NT-proBNP and troponin T demonstrated incremental predictive value assessed by net reclassification improvement and integrated discrimination improvement.
The study suggests that left atrial volumetric indices and established biomarkers are robust predictors of incident atrial fibrillation and can be used together for that purpose. GDF-15 however, does not seem to be useful for prediction of atrial fibrillation.
The study was published in Heart. Link here.