Commentary by Michael Poles MD, Associate Editor, Clinical Correlations
This week seems like a continuation of last week in a couple of ways. Last week our Editor-In-Chief, Dr. Neil Shapiro, wrote about the epidemic of MRSA. This hit closer to home when it was reported in the lay-press that a 12-year old Brooklyn student died of an overwhelming MRSA infection that arose from a skin lesion. I implore all physicians to consider the effect of indiscriminate use of antibiotics. Furthermore, perhaps it is time to think about getting antibiotics out of agribusiness. Also, under the auspices of things that never change, Congress is again poised to present a revised SCHIP bill to the President, who will undoubtedly veto it.
Though consensus is often hard to find, apparently the four cardiologic societies (American College of Cardiology (ACC), American Heart Association (AHA), European Society of Cardiology (ESC), and the World Heart Federation (WHF)) know how to play nicely together and have reached a consensus on the definition of myocardial infarction. This new consensus identifies five separate MI categories based on differences in pathophysiology and whether PCI or CABG surgery is involved. Troponin remains the preferred biomarker, but CK-MB can suffice when troponin testing is unavailable. The authors hope to get away from using distinctions such as transmural vs nontransmural or Q-wave vs non-Q-wave MI, and even ST-elevation and non-ST-elevation in our definition of MI. They recommend, that in the future we characterize infarction by the following 5 categories:
1. Spontaneous MI related to ischemia due to a primary coronary event, such as plaque erosion and/or rupture, fissuring, or dissection
2. MI secondary to ischemia due to an imbalance of O2 supply and demand, as from coronary spasm or embolism, anemia, arrhythmias, hypertension, or hypotension
3. Sudden unexpected cardiac death, including cardiac arrest, often with symptoms suggesting ischemia with new ST-segment elevation; new left bundle branch block; or pathologic or angiographic evidence of fresh coronary thrombus, in the absence of reliable biomarker findings
4a. MI associated with PCI 4b. MI associated with documented in-stent thrombosis
5. MI associated with CABG surgery
A new study in the November Journal of Clinical Investigation suggests that the use of some antihypertensive medications might lower an individual’s risk of developing Alzheimer’s disease. The authors of this study, from Mount Sinai School of Medicine, examined over 1000 drugs, looking for a benefit in the treatment of Alzheimer’s disease and dementia. They identified 7 out of 55 candidate antihypertensives that may prevent the production of beta-amyloid. In a mouse model of Alzheimer’s disease, they showed that the use of very low doses of Valsartan, Propranolol, Carvedilol, Losartan, Nicardipine, Amiloride and Hydralazine prevented the production of beta-amyloid. While further studies must be carried out in humans, the data are nonetheless intriguing, though this blogger wonders why we still see so much Alzheimer’s disease given the widespread use of these medications.
Lastly, if you have ever had to take a young child to their pediatrician to receive a vaccination, you will be happy to know that the CDC declared that children as young as two years old can be safely given the intranasal influenza vaccine, FluMist. While the CDC recommends that all children ages six months to five years receive the influenza vaccine, only 20.6% were fully vaccinated in 2005-2006. This aerosolized vaccine contains attenuated virus, but is not indicated for children under two years old as trials showed an increased risk of hospitalization and wheezing. I am sure that all parents will be happy to not have to hold a squirming child while they receive their shot. Unfortunately, there are still too many other necessary IM vaccines.
Image courtesy of Wikimedia Commons