Screening for Long-Term Cardiac Status During Cancer Treatment

Advances in early cancer detection and treatment have resulted in patients living longer after diagnosis. According to the Centers for Disease Control and Prevention1 about 12 million cancer patients survived in the United States in 2007, two thirds of whom were expected to live at least 5 years after the diagnosis.Article see p 596 With increases in survival time, the long-term adverse effects of various cancer treatments have become a subject of concern. Chemotherapeutic agents and radiation can cause several such effects; the cumulative incidence of chronic health conditions 30 years after cancer diagnosis can be as high as 75%.2 In particular, the number and severity of adverse cardiovascular effects increase with increasing doses of cardiotoxic chemotherapeutic agents3,4 as well as with increasing age,5,6 making these effects a large portion of these chronic health conditions.The onset of the cardiotoxic effects of cancer treatment can be early or late. Late effects usually manifest as dilated cardiomyopathy or arrhythmias. Diastolic dysfunction manifests earlier than any signs or symptoms of clinical heart failure. Given the incidence and timing of these effects, several echocardiographic measures and cardiac biomarkers have been proposed to identify and predict their long-term adverse cardiovascular outcomes.In this issue of Circulation: Cardiovascular Imaging , Sawaya et al7 tried to identify predictors of early-onset cardiotoxicity, which are those presenting during the first year after therapy. Among 81 women with newly diagnosed breast cancer related to human epidermal growth factor receptor 2 overexpression (positive) that had been treated with anthracyclines followed by taxanes and trastuzumab, 26 (32%) developed cardiotoxicity. The investigators used strain and strain-rate ultrasound imaging, which are echocardiographic modalities based on tissue Doppler imaging that can measure regional myocardial wall motion and assess left ventricular (LV) systolic and diastolic …