Medically Reviewed by: Dr. Brian Koffman
The Bottom Line:
A newly published paper in JAMA Oncology found that among cancer patients with suspected ibrutinib-related cardiotoxic effects, the presence of heart muscle injury and scarring is high, and this is associated with an increased risk of developing future cardiovascular adverse events.
Who Performed the Research and Where Was it Presented:
Dr. Benjamin Buck from the Ohio State University and colleagues published their findings in JAMA Oncology in 2023.
Background:
Ibrutinib is a Bruton tyrosine kinase (BTK) inhibitor that has revolutionized the treatment of chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL) and greatly improved patient outcomes. However, ibrutinib use can also cause cardiovascular side effects, including abnormal heart rhythms (atrial fibrillation) and high blood pressure. In clinical trials, significant numbers of patients taking ibrutinib experienced atrial fibrillation. In animal studies, the development of abnormal heart rhythms while on ibrutinib is often accompanied by damage to the heart muscle, including inflammation and scarring. However, it is unknown whether these changes also happen in humans. Dr. Buck and colleagues used cardiac magnetic resonance imaging (MRI) to determine the prevalence of heart muscle injury in patients with ibrutinib-related cardiac side effects.
Methods and Participants:
This was a cohort study of patients with blood cancers treated with ibrutinib between 2012 and 2019 at the Ohio State University Comprehensive Cancer Center. The study included patients referred for cardiac MRI due to unexplained abnormal heart rhythms or cardiac disease. Researchers looked for the presence of cardiac fibrosis (scarring of the heart muscle) using MRI, and they also looked at patient records to see if patients developed any “major adverse cardiovascular events,” which includes heart failure, sudden death, or abnormal heart rhythms (arrhythmias) that cause noticeable symptoms.
Results:
- In total, 33 patients with cancer were evaluated in this study, and 82% had chronic lymphocytic leukemia.
- 70% of patients had ibrutinib-related arrhythmias (abnormal heart rhythms).
- Patients had been taking ibrutinib for a median of 14 months before testing.
- Nearly 2/3 of patients had evidence of heart muscle injury, and 55% had scarring of the heart muscle (fibrosis).
- The prevalence of scarring in ibrutinib-treated patients was significantly greater than that observed in patients with similar traditional cardiovascular risk factors.
- Among those on ibrutinib without traditional cardiovascular risk factors, 16 (58.6%) had fibrosis on the MRI compared to 38 (13.3%) in matched controls.
- Patients with scarring of the heart muscle had increased rates of subsequent major adverse cardiovascular events. Over a median follow-up of 19 months, 13 (39.4%) experienced a major adverse cardiovascular event.
Conclusions:
Among cancer patients with suspected ibrutinib-related cardiotoxic effects, the presence of heart muscle injury and scarring is high. This damage to the heart muscle is associated with an increased risk of developing future cardiovascular adverse events. While this research is in an early phase and needs to be confirmed with larger multicentered trials, it does warrant more investigation. It may be part of our increased understanding of the cardiac risks with ibrutinib.
Links and Resources:
While the entire article is currently paywalled, you can read the abstract here: Cardiovascular Magnetic Resonance Imaging in Patients With Ibrutinib-Associated Cardiotoxicity
Take care of yourself first.
Ann Liu, PhD
