Cell-free DNA as a promising marker for risk stratification of pulmonary embolism

Arnalich and colleagues reported an interesting clinical study that evaluated cell-free plasma mitochondrial and nuclear DNA concentrations in patients with pulmonary embolism (PE) [1]. They found increased circulating mitochondrial and nuclear DNA levels, as well as alterations in other cardiac biomarkers (heart-type fatty acidbinding protein and troponin I) in patients with massive PE compared with those found in patients with submassive PE [1]. Importantly, all these biomarkers were found at higher concentrations in fatal massive PE than in nonfatal PE [1]. I would like to add experimental information associating cell-free DNA and acute pulmonary thromboembolism (APT). Experimental evidence showed that cell-free DNA concentrations increase in proportion to the severity of experimental APT [2]. In addition, these previous findings suggest that lysed cells from the thrombi are