Tuesday, November 18, 2014

Of Solid and Obsolete

by: Shahir Nazri

1. Person who suffers ischemic heart disease may develop ischemic mitral regurgitation. Unlike mitral regurgitation that occurs secondary to damaged valve leaflets or damaged chorda tendinae, ischemic mitral regurgitation occurs due to abnormal wall contraction secondary to myocardial injury. The valve leaflets remain normal in this case.

Minor ischemic mitral regurgitation can largely benefit from coronary artery bypass grafting (CABG) alone. But in case of moderate ischemic mitral regurgitation, surgeons are divided whether or not to include mitral valve repair (not replacement) with CABG. Keep in mind that the valves are completely normal in this case. Should we interfere?

A group argues that CABG alone can sufficiently slows down remodelling. Revascularization can improve left ventricular wall function, reducing left ventricular chamber size and increase mitral valve function, thus reversing the regurgitation. Furthermore, valvular repair operation can cause many complications (what can go wrong when you open the heart?).

Yeay, new record!

Another group advocates the inclusion of mitral valve repair with CABG. It is like a pre-emptive strike, where they try to stop the worsening of the regurgitation before it occurs, thus prevent remodelling of the heart and later heart failure.

If you are interested to know which triumph over which, here is a recent cohort study comparing both approaches: Surgical Treatment of Moderate Ischemic Mitral Regurgitation

2. Aortic root enlargement is a major problem in Marfan’s syndrome. Standard therapy of Marfan’s syndrome includes atenolol (Beta-blocker) administration in preventing aortic root enlargement. Atenolol acts by relaxing the heart and blood vessels to decrease the blood pressure, thus halting the expansion of root of aorta.

Mr. Marfan?

Losartan (ARB) can also reduce blood pressure by blocking the action of angiotensin-II (which cause vasoconstriction). In addition to reducing blood pressure, losartan also has the ability to block transforming growth factor- β (TGF-β) signalling. Excessive signalling of TGF-β is currently thought to cause the phenotypic character of Marfan’s syndrome, including the aortic root enlargement (read more about this somewhere, for I am too lazy to know more). Therefore, theoretically, losartan have the upper hand in preventing aortic root enlargement compared to atenolol.

Or is it? Find out more from this recent study here: Atenolol versus Losartan in Children and Young Adults with Marfan's Syndrome 

3. By the way, feeling obese? If so, you might want to drink more coffee after you read this: Chemical in coffee may help prevent obesity-related disease 
"And obese no more!". Why is she still keeping the pants then?

Do things with passion or not at all.

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