Can you give beta blockers to a CHF patient?

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HiddenTruth

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Here's a question for you guys. I see this happening in our clinics all the time, but is it necessarily correct? I don't know. Can you give beta blockers to a person who has congestive heart failure? Shouldn't you only administer beta blockers to patients who have CHF if they are previously on diuretics and are stabalized? Some feedback would be greatly appreciated. Thanks.

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I'm sorry guys there is already a post up here explaining all this..my bad....
 
The reason why they are beneficial is because in CHF, one of the deleterious effects that takes place is cardiac remodeling. Initially, it's beneficial because the heart hypertrophies to maintain wall stress (wall stress = [P x R]/thickness) and maintain cardiac output. But over time, it becomes so darn thick that ventricular filling is impaired and myocardial O2 delivery becomes impaired. When this happens, you get end stage heart failure and the patient is in deep ****. Now what causes this remodeling to occur? The answer: angiotensin II. Remember, AT-II is formed thru the renin-angiotensin cascade which is highly upregulated in individuals with CHF.

B-blockers DAMPEN the response of the sympathetic NS so that NOT AS MUCH AT-II is formed. There is still some AT-II being generated but not as much. Clearly, SOME hypertrophy is beneficial. Therefore, by giving a B-blocker, cardiac remodeling is maintained within normal physiologic limits. This is one reason why B-blockers are useful in CHF.

Another reason why B-blockers are used is because persistent sympathetic stimulation activates pro-apoptotic myocardial genes which results in ...... apoptosis!!! Apoptosis (or death) to the myocardium clearly cannot be a good thing!!! B-blockers BLOCK the activation of these proapototic proteins.

Now the reason for using B-blockers in asymptomatic individuals is to BLOCK all of these deleterious effects from occuring over time. This is why you use it when the patients are asymptomatic... to block the aforementioned progression of events.

During ACUTE CHF, the heart can no longer pump out the 5L/min that it is supposed to because the damn heart is worn out, it's hypertrophied like a mo-fo, isn't being perfused very well cuz it's so damn thick, isn't filling well because it's walls are so thick and noncompliant. As a result, pulmonary congestion ensues and this is when the patient returns to the hospital and is drowning in their lungs (ie severe pulmonary congestion). So what are we going to do?

We give a powerful B1 agonist like dobutamine to increase myocardial contractility and hopefully alleviate some of the pulmonary congestion. We're obviously going to use other drugs like a diuretic and vasodilator to help improve the sxs. But in the case of end stage CHF, there isn't much you can do except to try and alleviate the symptoms because the patient is pretty much down for the count.

Now as you mentioned, we definetely do NOT want to give a B-blocker in ACUTE CHF because it'll do the opposite of what we want.

Remember, for people with CHF that are asymptomatic, B-Blockers are NOT the only drug they're receiving. They're definetely going to be on a diuretic (Fursemide, hydrochlorothiazide) to reduce total volume and decrease afterload. They're also likely going to be on an ACE inhibitor for the same reasons. By giving this COMBINATION of drugs, the hope is that we will have relieved some of the pressure in the pulmonary system such that no congestion is occuring.
 
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