Mangold A, Ondracek AS, Hofbauer TM, et al. - Researchers sought to determine plasma concentrations of double-stranded DNA, deoxyribonuclease activity and outcome following transcatheter aortic valve replacement (TAVR), in this observational analysis. This study included 345 consecutive patients receiving TAVR as well as 100 healthy reference controls. It was found that baseline double-stranded DNA in plasma was significantly higher relative to healthy controls, was elevated at 3 and 7 days post-TAVR, and reduced after that. Reduced baseline deoxyribonuclease activity, vs healthy controls, was observed. Outcome 12 months post-TAVR was strongly and independently predicted by deoxyribonuclease activity. Thus, experts suggest the utility of deoxyribonuclease activity as a potential biomarker for risk stratification post-TAVR. Exploration is warranted for pathomechanisms of bioprosthetic valve deterioration involving extracellular DNA and deoxyribonuclease.