Dr Carolyn Lam: Welcome to Circulation on the Run, your weekly podcast summary and backstage pass to the journal and its editors. I'm Dr Carolyn Lam, associate editor from the National Heart Center and Duke National University of Singapore. Dr Greg Hundley: And I'm Greg Hundley, associate editor and Director of the Pauley Heart Center at VCU Health in Richmond, Virginia. Dr Carolyn Lam: We've got a juicy, juicy feature discussion coming up. It's on a pre-specified analysis of the ODYSSEY OUTCOMES randomized clinical trial, this time to ascertain whether PCSK9 inhibition reduces the risk of peripheral arterial disease events or venous thromboembolism after acute coronary syndrome. And, also to answer, these effects are related to levels of lipoprotein(a) or LDL cholesterol. I'm going to keep everyone guessing, as we get on our coffee chat and talk about the other papers in this issue. And I want to go first, because the first original paper I want to discuss is really quite related to the feature discussion too. And it asks the question, what is the relationship between cholesterol levels and risk of venous thromboembolism? And, what is the effect of PCSK9 inhibition on the risk of venous thromboembolism? So this is from Dr Marston from the TIMI Study Group, Brigham and Women's Hospital, Harvard Medical School in Boston, Massachusetts, and colleagues who performed a post hoc analysis of the FOURIER trial, testing whether evolocumab reduces the risk of venous thromboembolic events. That is, deep venous thrombosis, a pulmonary embolism. The authors then looked at data from FOURIER and the ODYSSEY OUTCOMES trial and combined them in a meta-analysis to assess whether there was a class effect of PCSK9 inhibition on the risk of venous thromboembolism. As a reminder, the ODYSSEY OUTCOMES trial tested alirocumab as the PCSK9 inhibitor. Dr Greg Hundley: Well, Carolyn, what did they find? Dr Carolyn Lam: Well, first Greg, remember, this is the first study to demonstrate a significant reduction in venous thromboembolism with PCSK9 inhibition. Interestingly, the reduction in venous thromboembolism was associated with the degree of lipoprotein(a) lowering and not LDL cholesterol lowering, suggesting that lipoprotein(a) may be the mediator of venous thromboembolic risk. More coming up in our feature discussion. Dr Greg Hundley: Wow, Carolyn. Well, I'm going to go into the world of PCSKs, but talk about PCSK6. So this study involves a secretome analysis of cardiomyocytes as novel players in cardiac remodeling after myocardial infarction and the corresponding author is Dr Florian Leuschner from Heidelberg University. So Carolyn, we know that acute occlusion of coronary artery results in swift tissue necrosis and bordering areas of the infarcted myocardium may also experience impaired blood supply and reduced oxygen delivery leading to altered metabolic and mechanical processes. While transcriptional changes in hypoxic cardiomyocytes are well-studied, little is known about the proteins that are actively secreted from these bordering cells. So in this study, the authors established a novel secretome analysis of cardiomyocytes by combining stable isotope labeling and click chemistry with subsequent mass spectrometry analysis. Dr Carolyn Lam: Wow, sounds like very advanced methods and what did they find? Dr Greg Hundley: Okay. Carolyn lots of results here. They found that PCSK6 expression was elevated in hearts of mice, following three days of ligation of the left anterior descending artery, a finding confirmed by immunohistochemistry. ELISA measurements and human serum also indicated distinct kinetics for PCSK6 in patients suffering from acute myocardial infarction with a peak on day three post infarction. One of these beautiful studies combining basic science and human subjects in the same paper. In addition, adeno-associated virus nine mediated cardiomyocyte specific overexpression of PCSK6 in mice resulted in increased collagen expression and