Navigating Cardiotoxicity: A Practical Guide to Cardiac Biomarkers during Chemotherapy

This is a verbatim transcript of an interview conducted with Prof Hyukjin Park in Oct 2025. The transcript has been lightly edited for clarity.

Why is cardiotoxicity an increasing concern in cancer treatment today?

With advances in cancer diagnosis and treatment, survival rates have improved. As a result, we now see more patients living long enough to experience cardiotoxicity related to cancer therapies. Traditionally, agents like Anthracycline and HER2-targeted therapies are well known for causing myocardial toxicity, often referred to as cancer therapeutics related cardiac dysfunction.

Beyond that, several tyrosine kinase inhibitors are linked with vascular toxicity and heart failure. While immune checkpoint inhibitors may cause acute myocarditis, pericarditis, or even accelerate atherosclerosis. Chest radiation can also contribute to cardiotoxicity. In terms of vulnerable groups, much depends on the therapy used, but in general, patients with preexisting heart failure or cardiovascular disease, older age, multiple cardiovascular risk factors, or elevated biomarkers such as natriuretic peptides or troponin are considered at higher risk.

How do cardiac biomarkers help in the early detection and management of cardiotoxicity?

Cardiac biomarkers are helpful for the early detection and management of cardiotoxicity. The two most widely used markers are troponin, which reflects myocardial injury, and natriuretic peptides, which reflect cardiac wall stress and heart failure risk. They are particularly useful during active cancer treatment because changes can appear before patients develop symptoms or before we see abnormalities on imaging.

For example, an early rise in troponin may signal subclinical injury, which should prompt closer clinical assessment and more frequent imaging follow up. NT-proBNP can help us track the risk of developing heart failure over time. Importantly, biomarkers are not meant to replace imaging, but they complemented. Biomarkers offer sensitive, repeated and cost effective monitoring, while imaging provides structural and functional context.

What does the process of integrating cardiac biomarkers into cardiotoxicity monitoring look like in practice? What do the guidelines recommend?

In practice, the integration of cardiac biomarkers into cardiotoxicity monitoring usually starts with a baseline measurement before initiating cancer therapy. This is especially important for for patients who are scheduled to receive potentially cardiotoxic agents. During treatment, follow up testing can be performed at predefined intervals, often aligned with chemotherapy cycles. In some high risk patients, more frequent monitoring may be considered.

When interpreting results, it is important to note that a rise in troponin or natriuretic peptides does not automatically mean cancer therapy should be stopped. Rather, it signals the need for close clinical evaluation and possibly repeat imaging to detect early functional changes. Depending on the patient’s individual CV risk profile and the specific cancer therapy being used, management should be individualised with considerations such as optimising CV risk factors or using cardioprotective strategies when appropriate.

As for guidelines, international guidelines provide a consistent message. The ASCO guidelines emphasise baseline CV risk assessment with biomarkers considered as a part of surveillance in selected patients. The ESC, a cardio-oncology guidelines go further, recommending routine, baseline and follow up measurement of troponin and naturetic peptides in patients receiving high risk therapies, particularly when combined with imaging. Importantly, these recommendations are not yet standardised worldwide and practice is often tailored based on institutional resources and patient risk profiles. Taken together, biomarkers are best viewed as a part of a multimodal monitoring strategy. They complement imaging and clinical assessment, helping us to detect cardiotoxicity earlier and manage patients more proactively.

What are some of the challenges clinicians may face when implementing biomarker-guided monitoring?

One challenge is the variability in how biomarkers are used. Some institutions or departments have integrated troponin and natriuretic peptides into routine monitoring, while others rely mainly on imaging or clinical symptoms, leading to inconsistent practice. Biomarkers should be used in integration with clinical assessment and cardiac imaging, and this combined approach is what we also apply at our hospital.

There are also logistical and resource related issues. The cost of repeated imaging, differences in assay availability and the need for rapid turnaround can be barriers, particularly in small centres. Standardising when and how often to test remains an ongoing challenge. Finally, effective use of biomarkers depends on strong collaboration between oncology and cardiology teams. Results need to be interpreted in the right clinical context, and that requires clear communication and shared protocols. Multidisciplinary discussions or joint clinics can help ensure that biomarker information is translated into timely and appropriate patient care.

What advice would you give to clinicians looking to integrate cardiac biomarkers into their cardio-oncology practice?

My advice would be to start simple. Begin with baseline measurement of troponin and natriuretic peptides in patients who are scheduled to high risk cancer therapies, as well as in patients who have higher CV risk profile and then repeat testing at key point during treatment. This provides a solid foundation and helps identify patients who may need closer follow up.

One common pitfall is to interpret biomarkers in isolation. Elevations should always be considered together with clinical assessment and cardiac imaging, rather than driving treatment decisions on their own. Establishing clear communication channels with oncology colleagues is also essential because collaboration is what makes biomarker data actionable. In the long run, this approach can improve outcomes by detecting cardiotoxicity earlier, allowing timely intervention, and ultimately helping patients not only survive cancer, but also maintain good cardiovascular health.

The views and opinions expressed by Prof Hyukjin Park are his own views and opinions. Roche disclaims all liability in relation to these views and opinions.