20 Aug 2012
Selections from Richard Lehman’s Literature Review: August 20th
CardioExchange is pleased to reprint selections from Dr. Richard Lehman’s weekly journal review blog at BMJ.com. Selected summaries are relevant to our audience, but we encourage members to engage with the entire blog.
Arch Int Med 13/27 Aug 2012 Vol 172
Examining the Benefits of Drug-Eluting vs. Bare-Metal Stents (pg. 1145): The only piece of information about coronary stents that has stuck with me over the fourteen years that I have been reporting about them is that bare metal stents are perfectly good for most purposes, except where there is a high risk of stenosis, in which case drug-eluting stents (DES) have a marginal advantage. This does not vary much between the various drugs eluted, but it is very important for patients to take daily clopidogrel for at least a year afterwards. In the USA, it is quite common to put drug-eluting stents into people who cannot afford the cost of clopidogrel, which means that their rates of immediate restenosis are actually higher than if they had bare metal. This study concludes, ”Use of DES in the United States varies widely among physicians, with only a modest correlation to patients’ risk of restenosis. Less DES use among patients with low risk of restenosis has the potential for significant cost savings for the US healthcare system while minimally increasing restenosis events.” Who knows: in the wonderland that is American interventional cardiology, it might even reduce them.
Walking Speed, High BP, and Mortality in the Elderly (pg. 1162): This is the week we need to think hard about how to treat blood pressure. In a patient over 65, for example, what should you be measuring? Yes, the systolic. OK, the diastolic too. The pulse pressure—yes, good, that predicts heart failure without systolic dysfunction. But what about the walking speed? This intriguing study from a NHaNES cohort shows that an elevated SBP is associated with increased mortality in fast walkers alone among the elderly; among slow walkers neither DSB nor SDB predicts mortality, and among those who could not complete a walking test, high BP is a very strong predictor of reduced mortality.
Stroke and Bleeding in Atrial Fibrillation with Chronic Kidney Disease (pg. 625) is another nice Danish national registry study which shows exactly what you might expect: “Chronic kidney disease was associated with an increased risk of stroke or systemic thromboembolism and bleeding among patients with atrial fibrillation. Warfarin treatment was associated with a decreased risk of stroke or systemic thromboembolism among patients with chronic kidney disease, whereas warfarin and aspirin were associated with an increased risk of bleeding.” But nowhere in this study could I discover what they were actually talking about. “Chronic kidney disease” is a term now applied to anyone with an estimated GFR less than 60, meaning over 10% of the population; and by the same token it is a continuous variable. Here the authors state that 2.7% of their sample had “non–end-stage chronic kidney disease.” Yes, yes, but what does that mean? The sun is coming out, there is gardening to be done, and I am fed up with searching for information which needs to be in the first section of the summary.
BMJ 18 Aug 2012 Vol 345
Diagnosis and Management of Peripheral Artery Disease: The high standard of BMJ clinical reviews continues with an excellent piece on the diagnosis and management of peripheral artery disease. Thanks to the efforts of the tobacco industry, PAD will continue to flourish throughout the developing world. The BMJ should do its bit by removing its paywall and making these clinical reviews a standard source of high quality, unbiased information in countries such as China (288 million smokers), India (100M smokers), and Russia (31M).