SNIPPETS FROM JOURNALS

JAMA 27 Jan 2010 Vol 303
333 Paroxysmal atrial fibrillation can vary from a minor nuisance to a cause of intermittent angina and heart failure. This trial shows that catheter radiofrequency ablation is markedly effective in the first nine months for patients whose paroxysmal AF fails to respond to antiarrhythmic drugs. That said, they still carried on with these drugs (excepting amiodarone) and anticoagulation or antiplatelet therapy according to current guidelines. A particular joy for methodologists was the use in this trial of Bayesian boundaries to determine interim analysis times. Put like that, it instantly sounds boring, but honestly it isn't.
http://jama.ama-assn.org/cgi/content/abstract/303/4/333

BMJ 30 Jan 2010 Vol 340
249 Cardiac rehabilitation is now routinely recommended to everyone who survives a heart attack, but 60% don't turn up. From a large number of trials, reviewed in this paper, we know that it is equally effective when given at home. But this does mean that the rehab team has to be flexible, proactive and adequately staffed. Don't hold your breath as the recession cuts start to bite.
http://www.bmj.com/cgi/content/full/340/jan19_4/b5631
252 I suspect it's going to be increasingly common for anaesthetists to insist on patients having non-invasive cardiac stress testing before elective major non-cardiac surgery, and this large Canadian observational study lends some support to this policy - but only for people with known cardiovascular risk factors. I searched in vain for the Web Table A which might have gone some way to explaining the mechanism by which pre-op stress testing actually harmed some low risk patients - the text speculates that it might have been by foisting beta-blockers on them. Anyway, for those with 1-6 risk factors, there is a measurable mortality benefit, even though very few of them actually require an invasive cardiac procedure.
http://www.bmj.com/cgi/content/full/340/jan28_3/b5526

Arch Intern Med 25 Jan 2010 Vol 170
126 DASH it! As you read this paper showing that a low-fat, low salt diet really does bring down blood pressure by as much as a powerful antihypertensive drug - up to 16/10 mm Hg. That's when it's combined with a weight losing regime over 4 months. It would be very hard to maintain that over a longer period so let's settle for 11/7.5 as in the DASH alone group. http://archinte.ama-assn.org/cgi/content/abstract/170/2/126
136 But hang on - here is the opposite message. A diet of unlimited meat and a lot of fat (the low-carbohydrate ketogenic diet) achieved a much better BP reduction than a low-fat diet in this next study - 6/4.5 vs 4.5/O. Moreover the second group had help from orlistat. Both groups lost weight equally. The undoubted benefits of the DASH diet do not seem to derive from fat restriction. In fact they can probably be matched by a wide variety of less puritanical diets.
http://archinte.ama-assn.org/cgi/content/abstract/170/2/136

JAMA 20 Jan 2010 Vol 303
250 Snip, snip. You are a few seconds nearer to death. Your telomeres are shortening. Quick, grab some smoked salmon. "Among this cohort of patients with coronary heart disease, there was an inverse relationship between baseline blood levels of omega-3 fatty acids and the rate of telomere shortening over 5 years." If you can't get hold of oily fish, a good alternative source of omega-3 fatty acids is snake oil. Helps your telomeres. Live Longer With Snake Oil - it's official.
http://jama.ama-assn.org/cgi/content/abstract/303/3/250

NEJM 21 Jan 2010 Vol 362
217 The heart and lungs share a space in the thoracic cavity. When one gets bigger, the other gets squashed. This elementary fact is nicely illustrated by a study of 2816 people aged 45 to 84 without gross cardiovascular or lung disease. The more evidence of emphysema on lung CT scanning, the smaller the capacity of the left ventricle when filling. This means that the ejection fraction was not impaired but cardiac output was. This is nothing to do with cor pulmonale, mainly a problem of the right ventricle, or myocardial ischaemia, though in advanced COPD these may also play a part. O that cardiologists would remember that the chest contains lungs. It's difficult enough to get them to remember that the heart has two ventricles and a phase called diastole.
http://content.nejm.org/cgi/content/abstract/362/3/217
228 Which brings us nicely on to the topic of systolic heart failure, as reviewed here by John McMurray. Whenattending heart failure conferences there were ribs about trialling yet another drug on recumbent male patients aged 60 with reduced ejection fractions in hospital beds. It isn't the best way of informing us how to treat 75 year olds in the community with multiple morbidities including cardiac impairment. Still, we have to pick up what clues we can from what studies there are, though it would be a mistake to call this evidence-based medicine. It is called general practice, and it can be quite hard. Here are some of the easier bits for those who need an update.
http://content.nejm.org/cgi/content/extract/362/3/228
239 "The primary care physician remains the principal provider and care coordinator for patients with Williams-Beuren syndrome." Your practice may well contain such an individual, if your list is over 10,000. But you probably know this as Williams' syndrome without the Beuren - a microdeletion at chromosome 7 causing a characteristic facial appearance, hypercalcaemia, growth failure, heart abnormalities and learning difficulties. If you are a primary care physician who is the principal care provider for this person, you are not going to find a better review than this , so if you work in SWEssex you can have access to this via Athens
http://content.nejm.org/cgi/content/extract/362/3/239

Lancet 23 Jan 2010 Vol 375
283 Plato held that each earthly object was an imperfect approximation to an ideal object. Clopidogrel is your typical earthly product: expensive and disappointing, as it does nothing for about 30% of people who take it. Ticagrelor on the other hand sounds like the Platonic ideal for platelet inhibition - it works for everybody as it is not a pro-drug, but it is reversible and therefore should cause fewer bleeds. But how all the things of earth disappoint. The most striking thing about the PLATO trial is that ticagrelor is nowhere near 30% better than clopidogrel. This massive study in 13,408 people about to undergo invasive treatment for acute coronary syndromes showed a tiny difference in the composite end-point of death, myocardial infarction or stroke - 9.0% v 10.7% in favour of ticagrelor. There was no difference in bleeds. http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(09)62191-7/abstract

Ann Intern Med 19 Jan 2010 Vol 152
69 Here's a study from the USA which examines three strategies for the primary prevention of coronary artery disease using statins. Two are based on measurement of LDL-cholesterol ("treat to target") and the other is based on total estimated 5-year coronary risk ("tailored treatment"). "We assumed that LDL cholesterol reduction is a statin's sole mechanism of action and that change in total LDL cholesterol is a perfect indicator of the amount of risk reduction that a patient receives from a statin, thereby conceding the 2 most important assumptions underlying the treat-to-target approach. We realize that the first assumption is controversial and that the second assumption is untrue (LDL cholesterol determinations have substantial measurement error)." Neatly put. This is a modelling exercise set by Harlan Krumholz for his scholars and they do it beautifully: the most effective way to use these drugs is to give simvastatin 40mg to everyone with a 5-15% CAD risk and 40mg atorvastatin to everyone with a risk above that - and never mind the LDL-C.
http://www.annals.org/content/152/2/69.abstract
78 By and large it doesn't matter what you give patients to reduce their blood pressure so long as it works and they keep taking it. However, you may wish to bear in mind that exclusive treatment with calcium channel blockers may carry a higher risk of atrial fibrillation than beta-blockers and ACE inhibitors.
http://www.annals.org/content/152/2/78.abstract