Peptide Biomarkers for Long COVID Heart Damage: What Blood Tests Can Tell Us

This is a narrative review article that synthesizes the current literature on cardiovascular manifestations of long COVID and the biomarkers used for diagnosis, risk stratification, and therapy monitoring. The authors reviewed both established cardiac biomarkers with proven clinical utility and emerging candidates with preliminary evidence in the long COVID context.

Millions of people worldwide have long COVID, and cardiovascular complications are among the most dangerous. Many patients have subtle heart damage that standard exams miss. Peptide biomarkers like BNP and endothelin-1 can detect this damage through a simple blood test, potentially allowing early intervention before heart failure or other serious complications develop. Better biomarker strategies could personalize follow-up care for the millions of long COVID patients.

This review highlights how peptide biology is central to understanding and managing long COVID heart damage. Natriuretic peptides have been cornerstones of heart failure diagnosis for decades, and their relevance extends seamlessly to long COVID. The emergence of newer peptide markers like endothelin-1 and GDF-15 reflects a broader trend in medicine: using the body's own signaling peptides as diagnostic windows into disease processes. As long COVID research matures, these biomarkers may become standard components of post-infection cardiovascular screening.

As a narrative review, this paper does not perform meta-analysis or systematic evidence grading. Many of the emerging biomarkers lack large-scale validation studies specific to long COVID. There is no standardization in biomarker testing protocols across studies, making direct comparisons difficult. The review acknowledges the absence of validated longitudinal predictive models for cardiovascular outcomes in long COVID.