September 17th, 2012
Selections from Richard Lehman’s Literature Review: September 17th
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.
JAMA 12 Sep 2012 Vol 308
Surgical vs. Lifestyle Treatment for Type-2 Diabetes (pg. 981): “Considering the cost, invasiveness, inpatient requirement, and morbidity of bariatric surgery, a truly intensive nonsurgical comparison group is not only justifiable but also necessary to avoid scientific bias. A suitably intensive lifestyle intervention should include multiple components, such as residential treatment for several weeks to initiate rapid weight loss under medical supervision and development of a personalised treatment plan; home-based treatment for several months, with provision of prepared meals consistent with dietary goals, weekly sessions with a nutritionist and personal trainer, behavioural counseling, cooking classes, and membership to a sports or fitness club; and follow-up for several years, involving monthly sessions with nutrition and behavioral experts, group classes, and Internet and social media support. The financial costs of such an intervention would likely not exceed those of bariatric surgery.” This welter of wild surmise comes in the middle of a piece called surgical vs lifestyle treatment for type 2 diabetes. One of the authors is a deputy editor of JAMA, and the others work at the New Balance Foundation Obesity Prevention Center, Boston Children’s Hospital. It may be “necessary to avoid scientific bias” but I’ve never seen it done quite so comprehensively.
Omega-3 Fatty-Acid Supplementation and Risk for Major CVD Events (pg. 1024): The pleasures of oily fish are a matter of contention; but the benefit of fish oil in preventing cardiovascular disease events has been pretty definitely refuted in this widely publicized meta-analysis of 20 major studies of omega-3 supplementation by diet or supplements. My favourite fishy treat is a large, very fresh herring fried in butter; and could somebody please now do a meta-analysis proving that dairy fat has no association with heart disease? Not that I care in the least. Health is a subject that should never be mentioned at the table.
NEJM 13 Sep 2012 Vol 367
FAME 2: FFR-Guided PCI vs. Medical Therapy in Stable Coronary Disease (pg. 991):
Fame is the spur that the clear spirit doth raise
(That last Infirmity of Noble mind)
To scorn delights, and live laborious dayes
as Milton observed in his great elegy Lycidas (1637). FAME-2 is the reason I am living a laborious day instead of enjoying late summer sunshine in the garden. This is quite a tough trial for a non-cardiologist to unpack, but potentially practice-changing. When the COURAGE trial was reported 5 years ago, the pendulum swung away from percutaneous intervention for stable angina towards optimal medical therapy: usually aspirin, statin and beta-blocker. Because outcomes were identical, there now seemed little point in even performing coronary angiography on most of these patients. But for better or worse, FAME-2 looks like pushing the pendulum back towards invasive investigation, because it demonstrates a huge reduction in the need for urgent revascularization in patients who show functionally significant stenoses. And in order to demonstrate a functionally significant stenosis you have to go into the coronary artery with a wire sensor which measures the fractional flow reserve. If this is below 0.8, patients will benefit from a drug-eluting stent, to such an extent that the trial was stopped early. Cardiac catheter labs will fill up again, at least in the USA. And many will spend laborious days arguing about this trial, but I shall be elsewhere. Read the accompanying editorial, nicely entitled, “Which Is More Enduring—FAME or COURAGE?”
Arch Intern Med 10 Sep 2012 Vol 172
One-Hour Rule-out and Rule-in of Acute MI Using High-Sensitivity Cardiac Troponin T (pg. 1211): Cardiac troponin testing for myocardial infarction is a surprisingly recent phenomenon: I know it must be, because I can remember calling for its rapid adoption in one of these reviews in the early 2000s, when only 4 hospitals in England had the test available. Within a year they all had, and since then troponin measurement has changed both the definition and the management of MI throughout the world. But there is still that tedious wait of 6-12 hours to rule out MI in borderline patients with chest pain. Now that we have high sensitivity cardiac troponin T (hs-cTnT) tests, a lot of this may be avoided, according to this interesting European study which derived an algorithm for ruling out MI by two hs-cTnT measurements within the first hour of presentation at hospital with chest pain. When confirmed, this could lead to further major changes in practice and three-quarters of such patients walking home after just a couple of hours on the trolley.
Timing of Acute MI in Patients Undergoing Total Hip or Knee Replacement (pg. 1229): Scarcely a week goes by without some new gene locus or biomarker being heralded as a new risk factor for myocardial infarction on the basis of a hazard ratio of 1.27 or similar. Show me a hazard ratio of 25 or 30 and I’ll sit up and take notice. But then I am not an orthopaedic surgeon, and could never be mistaken for one; I drive an 11-year-old hatchback and wear a distracted, bookish air; I could never spring with annoying vigour from a brand-new Porsche left rakishly across two spaces in the private hospital car park. Someone needs to go over and tell these guys that total hip replacement is dangerous to the heart, and total knee replacement even more so. Above all, somebody needs to do an urgent trial of prophylactic aspirin and statins in these patients.