Advancing Bovine Cardiac Diagnostics: Integrating Echocardiographic Innovation and Serum Biomarkers

Cardiac disease in cattle is diagnostically difficult because structural lesions, myocardial injury, pulmonary vascular load and overt congestive heart failure may produce overlapping clinical signs while requiring different management decisions. Echocardiography has become the principal non-invasive method for defining bovine cardiac anatomy and hemodynamics, whereas serum biomarkers offer a complementary window on cardiomyocyte injury and myocardial stress. This critical narrative review evaluates how these approaches can be integrated without exceeding the strength of the current evidence. Literature from 1 January 1990 to 24 June 2026 was examined, with emphasis on bovine studies that established reference echocardiographic values, evaluated structural or functional abnormalities, assessed myocardial deformation or pulmonary hypertension, or investigated cardiac troponin I, heart-type fatty acid-binding protein and N-terminal pro-B-type natriuretic peptide. Conventional two-dimensional, M-mode and Doppler echocardiography are well supported for lesion localization, pericardial disease, congenital defects and gross chamber or valvular abnormalities, but interpretation remains dependent on age, body size, breed, loading conditions and operator technique. Speckle-tracking echocardiography and right-ventricular strain provide mechanistically attractive measures of myocardial function, yet bovine validation remains limited to small experimental or feasibility studies. Cardiac troponin I is the best-supported circulating marker of myocardial injury in cattle, including histologically validated toxic injury, but it is not disease-specific and may increase in systemic inflammatory, infectious, metabolic and respiratory disorders. Emerging biomarkers such as heart-type fatty acid-binding protein and N-terminal pro-B-type natriuretic peptide have shown promising discrimination in small case-control studies, but reported thresholds and near-perfect receiver-operating characteristics require external validation against independent cardiac reference standards. The evidence therefore supports a multimodal, syndrome-oriented diagnostic strategy in which echocardiography defines anatomical and functional phenotype while biomarkers identify or monitor myocardial injury or stress. Priority research should establish age- and production-stage-specific reference intervals, assay harmonization, longitudinal multimodal cohorts, disease-specific validation and field-relevant decision thresholds linked to clinically meaningful outcomes.