September 1st, 2014
Selections from Richard Lehman’s Literature Review: September 1st
Richard Lehman, BM, BCh, MRCGP
CardioExchange is pleased to reprint this selection 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.
NEJM 21-28 August 2014 Vol 371
Aortic-Valve Stenosis — From Patients at Risk to Severe Valve Obstruction (pg. 744): If you are looking for a good clear summary of aortic valve stenosis, and have access to full text of the NEJM, this is the one to go for. I well remember a patient with aortic valve disease who refused surgery because his symptoms were mild although his pressure gradient was critical. He finally agreed but went into crashing heart failure while waiting for surgery. He didn’t make it. AS gets quite common as we age. Most of it is harmless, but the only way to know is to get an echo.
Cardiovascular Risk and Events in 17 Low-, Middle-, and High-Income Countries (pg. 818): More epidemiology, this time a survey of Cardiovascular Risk and Events in 17 Low, Middle, and High Income Countries, good for poring over on a wet afternoon. You need to pore a bit to try and understand the paradox that emerges from this enormous data analysis: “Although the risk factor burden was lowest in low income countries, the rates of major cardiovascular disease and death were substantially higher in low income countries than in high income countries.” The authors put this down to better treatments for risk factors in high income countries, but I am not convinced. In a sense, this is a validation study of the INTERHEART Risk Score, which proves that it is not predictive of real outcomes in whole populations.
JAMA 20-27 August 2014 Vol 312
Recognizing Worsening Chronic Heart Failure as an Entity and an End Point in Clinical Trials (pg. 789): Twenty years ago, when I was new to the wonderful world of heart failure trials, I can remember arguing with a keen young researcher about hospitalization as an end point. Surely, I said, rates of hospitalization vary hugely between systems and within systems, and are to a major extent driven by the adequacy of support systems within primary care. I’ve been making this point ever since and thought nobody was listening. Those three mighty cardiologists, Javed Butler, Eugene Braunwald, and Mihai Gheorghiade certainly weren’t listening, because I’ve never been near them, but in this piece they make exactly the same point. Make “worsening chronic heart failure” a primary end point for HF trials, not hospitalization.
Effect of Self-monitoring and Medication Self-titration on Systolic Blood Pressure in Hypertensive Patients at High Risk of CVD (pg. 799): Who is the best person to monitor blood pressure? It’s a no-brainer really. TASMIN-SR was a primary care, unblinded, randomized clinical trial involving 552 patients who were aged at least 35 years with a history of stroke, coronary heart disease, diabetes, or chronic kidney disease, and with baseline blood pressure of at least 130/80 mm Hg being treated at 59 UK primary care practices. And it showed that self-monitoring with self-titration of antihypertensive medication, compared with usual care, resulted in lower systolic blood pressure at 12 months. A great study, but just a start. Now we need to see how people might choose their own treatments based on absolute risk reduction.
JAMA Intern Med August 2014
How Cardiologists Present the Benefits of PCIs to Patients With Stable Angina (OL): COURAGE, mes amis. People with chronic stable coronary disease do just as well on maximal medical treatment as after revascularization procedures. Putting stents in the pipes does not prevent more infarcts than taking pills. This is what the COURAGE trial taught us in 2007. But seven years later, one third of PCIs in America are still being done for stable CAD. This is the first of three papers exploring the problem. In 40 observed consultations, “Few cardiologists discussed the evidence based benefits of angiogram and PCI for stable CAD, and some implicitly or explicitly overstated the benefits.”
The Effect of Information Presentation on Beliefs About the Benefits of Elective PCI (OL): So that’s what cardiologists do when qualitative researchers are watching. What do the patients themselves think? The next study examines the effect of “explicit and explanatory information on participants’ beliefs about PCI and their willingness to choose it.” This was a big trial, but the 1257 participants who completed the questionnaire did not have CAD. They were simply asked to think about three scenarios in which they experienced class I angina and were referred to a cardiologist. “In the setting of mild, stable angina, most people assume PCI prevents MI and are likely to choose it. Explicit information can partially overcome that bias and influence decision making.” So the question left hanging in the air is how we can best bring this explicit information to people who are about to make a real life decision, in such a way as to change the practice of cardiologists who often have a financial interest in unnecessary angiography and PCI.
Patient Selection for Diagnostic Coronary Angiography and Hospital-Level Percutaneous Coronary Intervention Appropriateness (OL): Because there’s no doubt that when cardiologists do an angiogram and see a stenosis, they itch to put in a stent. This is called the “oculostenotic reflex,” and its existence is proved by an observational study of 544 US hospitals. “In a national sample of hospitals, performance of coronary angiography in asymptomatic patients was associated with higher rates of inappropriate PCI and lower rates of appropriate PCI.” COURAGE, mes chers amis cardiologiques. Have the boldness to ignore the narrowing and remember the evidence. Even better, have the boldness not to do an angiogram in the first place.
Lancet 23-30 August 2014
Pulse Oximetry with Clinical Assessment to Screen for Congenital Heart Disease in Neonates in China (pg. 747): Several studies over recent years have shown that pulse oximetry in the neonatal period can help to detect congenital heart disease. This one comes from Shanghai and its message to the authorities is clear: “Pulse oximetry plus clinical assessment is feasible and reliable for the detection of major congenital heart disease in newborn babies in China. This simple and accurate combined method should be used in maternity hospitals to screen for congenital heart disease.” Cut to picture of enormous postnatal ward with a hundred cots containing tiny babies with little clips on their fingers.
The BMJ 23 August 2014 Vol 349
Use of Clarithromycin and Roxithromycin and Risk of Cardiac Death: One reason you should never prescribe clarithromycin to people at high cardiovascular risk is because such people should all be taking statins, which can cause fatal rhabdomyolysis with clarithromycin. But that applies to all macrolides. Another reason is that clarithromycin itself seems to increase cardiac death even in seven day courses, compared with the closely similar roxithromycin. This emerges from a huge Danish database study, and makes you wonder if clarithromycin should now be withdrawn, given the number of safer alternatives.