Vitals during an MI

Altra, BSN, RN · Jun 11, 2012

No ... a number of variables and any number of underlying causes of infarction mean there is no rule of thumb.

wowza · Jun 12, 2012

It depends on the type of heart attack (ie what part of the heart it affects). In most cases, the heart rate will increase. This is attenuated by the fact that most people who have an MI will also be on a beta blocker already. In terms of blood pressure, it depends on the area of the heart involved and how severe the MI is. A massive LAD or L main MI (anterior MI) will cause severe hypotension (cardiogenic shock). The treatment is quite different for RCA infarcts. Inferior or posterior MIs (RCA infarcts and sometimes infarcts of branches off of the LCx) can, but less often cause hypotension. However, these types of MIs are very, very sensitive to pre-load so any medications that either decrease cardiac output or change pre-load will cause hypotension. Less severe MIs will often be associated with hypertension. This is actually a pretty good prognostic sign as it shows that the pumping function of the heart is preserved.

Esme12, ASN, BSN, RN · Jun 12, 2012

Any MI may cause hypotension if it covers a large enough area of muscle and is an indicator of prognosis I disagree with wowza and I have found inferior and true posterior (right ventricular) wall MI are more likely to cause hypotension as they affect the "pumping chamber" of the heart the left ventricle.

"Certain clinical features (the hypotension, bradycardia, and heart block) would all be compatible with RVMI. "

Management of Acute Myocardial Infarction With Hypotension*

Ashleyjo18 · Jun 16, 2012

Inferior MI's with right sided involvement will generally cause hypotension. That's because it's affecting the part of the heart that pumps blood to the rest of the body. If they're beta-blockers, their HR will stay in the 60-80 range and they can't compensate for a drop in BP. Any MI can cause hypotension since they all affect the heart and the hear has to be working to pump anything out. I know we're cautious with nitro in an inferior MI because if the additional drop in BO.

wowza · Jun 18, 2012

Any MI may cause hypotension if it covers a large enough area of muscle and is an indicator of prognosis I disagree with wowza and I have found inferior and true posterior (right ventricular) wall MI are more likely to cause hypotension as they affect the "pumping chamber" of the heart the left ventricle. "Certain clinical features (the hypotension, bradycardia, and heart block) would all be compatible with RVMI. "Management of Acute Myocardial Infarction With Hypotension*

Esme, I probably should have qualified my statement. RV infarcts can cause hypotension but are much easier to correct and usually much more benign than LV infarcts*So hypotension in an anterior MI means the pump failed. Hypotension in an RV infarct is often a pre-load issue that can quickly be corrected. Anterior infarcts causing hypotension can be corrected only with some pretty extreme interventions because the pump has failed- balloon pumps or inotropes until the initial stunning of the myocardium is corrected. Even then, often teh scarring is so severe you get an ischemic cardiomyopathy. It is rare to get an ischemic cardiomyopathy from an RV infarct unless a left dominant circulation with a massive infarct. Now the above is also dependent on the anatomy. If the patient is left dominant, the LCx will probably be the occluded vessel so it will be assocaited with inferior or lateral changes in addition to posterior changes. This means a large portion of myocardium will be involved and actually will involve portions of the LV, rather than just the RV. With regard to the bradycardia or heart block, these too are usually short lived and resolve with reperfusion of the AV node.

silverhalide · Mar 7, 2013

What about the pulse pressure with an MI? would it be narrow or wide?

turnforthenurse, MSN, NP · Mar 8, 2013

What about the pulse pressure with an MI? would it be narrow or wide?

More than likely narrow. The most common cause of a narrow pulse pressure is a drop in left ventricular stroke volume. Other causes include hypovolemia, shock, cardiac tamponade and aortic valve stenosis.

I also wanted to chime in regarding vital signs changes during an MI...it depends on where the MI is located and how extensive the damage is.

* Anterior MI (LAD) - tachycardia, SA blocks, pulmonary edema

* Inferior MI (RCA) - bradycardia, hypotension. They may also present with N&V and hiccups instead of chest pain. Anytime you have an inferior MI, do a right-sided EKG to check for RV involvement.

* Lateral (LCA, LCX) - ventricular dysrhythmias

* Septal (LAD, RCA) - tachycardia, atrial fibrillation

* Posterior (LCA, LCX, RCA) - bradycardia, junctional rhythms

* RV infarct - suspected with inferior MI, which is why if a patient presents with an inferior MI they need to have a right-sided EKG completed. Look for changes in V4R. The incidence of RV involvement is 40% with inferior wall MIs. You'll see hypotension, JVD and lungs CTA in a true RVMI.

silverhalide · Mar 12, 2013

Thanks!

gelarehm · Nov 20, 2015

I completely understand what you mean. This answer to this question appears to be in a grey area and it makes sense you haven't been able to find a clear-cut answer. One of my colleagues who's a Cardiovascular doctor recently wrote an article about this in a simple language:

What happens to human vital signs before and during a heart attack? - Ask Medical Researchers

Hope this helps you get a better answer.

uae808 · Nov 23, 2015

lung CTA stand for ???

vanilla bean · Nov 23, 2015

lung CTA stand for ???

Lungs clear to auscultation.