Radiotherapy-Induced Cardiotoxicity: The Role of Multimodality Cardiovascular Imaging

Abstract

Radiotherapy (RT) is one of the pillars of cancer therapy. High-dose radiation exposure on the thorax is mainly used in the context of adjuvant RT after breast surgery, in lung and esophageal cancer, and as a complement to systemic treatment in lymphoma. Due to the anatomical proximity, the heart inevitably receives some radiation that can result in acute and chronic cardiotoxicity, leading to heart failure, coronary artery disease, pericardial and valvular heart disease. Current evidence suggests there is no safe radiation dose to the heart, which poses a need for early recognition of RT-induced cardiac injury to initiate cardioprotective treatment and prevent further damage. Multimodality cardiac imaging provides a powerful tool to screen for structural and functional abnormalities secondary to RT. Left ventricular ejection fraction, preferably with three-dimensional echocardiography or cardiovascular magnetic resonance (CMR), and global longitudinal strain with speckle-tracking echocardiography are currently the key parameters to detect cardiotoxicity. However, several novel imaging parameters are tested in the ongoing clinical trials. CMR parametric imaging holds much promise as T1, T2 mapping and extracellular volume quantification allow us to monitor edema, inflammation and fibrosis, which are fundamental processes in RT-induced cardiotoxicity. Moreover, the association between serum biomarkers, genetic polymorphisms and the risk of developing cardiovascular disease after chest RT has been demonstrated, providing a platform for an integrative screening approach for cardiotoxicity. The present review summarizes contemporary evidence of RT-induced cardiac injury obtained from multimodality imaging—echocardiography, cardiovascular computed tomography, CMR and nuclear cardiology. Moreover, it identifies gaps in our current knowledge and highlights future perspectives to screen for RT-induced cardiotoxicity.

Radiation Treatment Mechanisms of Cardiotoxicity: A Systematic Review

“…Left ventricular ejection fraction (LVEF) has diagnostic and prognostic meaning for cancer patients, and with advancement, in 3D echocardiography, there is a more precise estimation of its value. Strain echocardiographic imaging is useful for the detection of preclinical adverse effects even before structural heart disease exists [ 5 ].…”

“…Nuclear cardiology is a powerful diagnostic tool helping everyday clinical practice detect of toxic effects of radiation treatment. SPECT and PET are very useful for the detection of coronary artery disease, but also heart failure and pericardial syndrome cases [ 5 ].…”

“…Radiation therapy is a common adjuvant cancer therapy to chemotherapy or surgery for many common types of cancer. Breast, lung, and esophageal cancer and lymphomas may expose the heart to the deleterious effects of irradiation [ 5 , 6 ]. There are several literature reviews suggesting possible mechanisms of cardiac toxicities of radiation therapy and treatment options [ 7 ].…”

Current Cardioprotective Strategies for the Prevention of Radiation-Induced Cardiotoxicity in Left-Sided Breast Cancer Patients

“…Furthermore, measuring specific biomarkers in BC patients' serum during or after RT could contribute to the prediction, diagnosis, and risk assessment of cardiovascular disease [40].Studies have shown that the appropriate biomarkers in patients undergoing RT include cardiac troponin T (cTnT), cardiac troponin I, and natriuretic peptides such as B-type natriuretic peptide (BNP) and N-terminal pro B-type natriuretic peptide (NT-proBNP) (cTnI). Elevated levels of these molecules may indicate increased myocardial stretch and thus may be used as biomarkers for left ventricular dysfunction and heart failure [41,42]. Although such biomarkers are insufficient on their own to determine the path of treatment for each patient, they should be used as a trigger or follow-up tool for the attending physician [43].…”

Impact of Systemic Autoimmune Diseases on Treatment Outcomes and Radiation Toxicities in Patients with Stage I Non-Small Cell Lung Cancer Receiving Stereotactic Body Radiation Therapy: A Matched Case-Control Analysis

“…Recently, the role of RIHD in patients with NSCLC has emerged as a topic of interest [ 27 ]. Previous studies have investigated the risk of cardiac toxicity and the effect of the cardiac radiation dose on survival in patients with NSCLC [ 28 , 29 , 30 ].…”