Right Ventricle and Radiotherapy: More Questions than Answers

Abstract

The injury of the left ventricle (LV) during anticancer therapy has long been recognized, and guidelines recommend a specific set of parameters for determination of LV impairment. The influence of anticancer therapy on the right ventricle (RV) has been insufficiently investigated, and there are only a few studies that have considered the effect of radiotherapy on RV remodeling. On the other hand, large number of patients with different types of cancers located in the chest are treated with radiotherapy, and the negative clinical effects of this treatment such as accelerated coronary artery disease, valve degeneration and heart failure have been documented. The anatomical position of the RV, which is in the front of the chest, is responsible for its large exposure during radiation treatment, particularly in patients with left-sided breast and lung cancers and mediastinal cancers (hematological malignancies, esophagus cancers, thymomas, etc.). For the same reason, but also due to its anatomical complexity, the RV remains under-investigated during echocardiographic examination, which remains the cornerstone of cardiac imaging in everyday practice. In the last decade many new echocardiographic imaging techniques that enable better evaluation of RV structure, function and mechanics appeared, and they have been used in detection of early and late signs of RV injuries in oncological patients. These investigations are related to some important restrictions that include limited numbers of patients, used parameters and imaging techniques. Many questions about the potential impact of these changes and possible predictions of adverse events remain to be evaluated in future large longitudinal studies. The current body of evidence indicates an important role of radiotherapy in RV remodeling, and therefore, the aim of this review is to summarize currently available data regarding RV changes in patients with various oncological conditions and help clinicians in the assessment of possible cardiac damage.

Right Ventricular Function in Long-Term Survivors of Childhood Acute Lymphoblastic Leukemia: From the CTOXALL Study

“…On the other hand, Christiansen et al found a prevalence of RVSD of 28.2% [8]. The underlying reason for this noticeable high prevalence may lie in the more intensive treatment received by the recruited survivors: the cumulative anthracycline dose was 150 (40-485) mg/m 2 , and 24% of them were exposed to radiotherapy, which appears to exert a particularly cardiotoxic effect on the RV due to its anterior anatomical position [25]. In addition, the lower limits of normal RV function were based on the distribution of the control group values, resulting in more lenient criteria for RV impairment.…”

“…The median age at diagnosis was 4 (3-8) years, and the median time elapsed from diagnosis to recruitment was 18 (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26) years. All the survivors were exposed to anthracyclines, but only three (3.3%) received radiotherapy.…”