Right Sided MI - How Do I Tell The Difference

[FL_Medic]

If you don't look, how do you know there is with certainty? Or if V1 and V2 appear normal, how do you know V8 and V9 are clear? Not all injury presents with reciprocal changes. (Playing Devil's advocate). I understand if it talks like a duck, it's probably a duck.

Well I meant with this EKG specifically. I'm not against checking the posterior leads, I just had already diagnosed STEMI on this patient with RV involvement. I was more concerned with Tx at that point. You are correct though, had I not had obvious changes indicating STEMI in other leads a posterior check would be more than indicated.

[kevkei]

Well I meant with this EKG specifically. I'm not against checking the posterior leads, I just had already diagnosed STEMI on this patient with RV involvement. I was more concerned with Tx at that point. You are correct though, had I not had obvious changes indicating STEMI in other leads a posterior check would be more than indicated.

Okay, ya, good point Duh!

[FL_Medic]

Remember, the right ventricle is only responsible for pulmonary circulation (lower pressure) where as the left ventricle (higher pressure) has to pump blood to the entire body and back.

In the setting of right ventricular infarction, the right ventricle can become "stunned" and fail to pump blood effectively. It essentially becomes a conduit through which blood flows. When this occurs, the patient becomes highly dependent on central venous pressure to maintain adequate cardiac output.

Sometimes, this is referred to as being "pre-load dependent" which is a term that I find amusing. In the first place, it's become a catch phrase, but more importantly, raise your hand if you're not pre-load dependent!

Because patients with a stunned right ventricle are dependent on central venous pressure to maintain cardiac output, it can be dangerous to give these patients nitroglycerin, which is a potent vasodilator. Morphine can cause problems for the same reason.

Patients with right ventricular infarction (almost always associated with inferior wall MI) tend to start out with borderline blood pressures. This is due in part to right ventricular stunning, but also because inferior MI often stimulates the Bezold-Jarisch reflex, which leads to a state of hypervagotonia. It's no accident that sinus bradycardia is the most common arrhythmia associated with inferior MI!

- EMS12lead.blogspot.com

Just though this was a good statement.

[WolfmanHarris]

+5 for new information. Didn't realize I'd been talking about "pre-load dependent" without thinking through what exactly NTG or MS will do to the patient systemically. Thanks for the great info and link!

- Matt

Edit: You're killing me FL_Medic. I hopped on here to take a break from a project and have spent the last half hour engrossed in that blog. I love the way he approaches topic on there, helps cement it way better than rereading my ECG book again. Highly recommend!

Edited April 24, 2009 by docharris

[kevkei]

Sometimes, this is referred to as being "pre-load dependent" which is a term that I find amusing. In the first place, it's become a catch phrase, but more importantly, raise your hand if you're not pre-load dependent!

Because patients with a stunned right ventricle are dependent on central venous pressure to maintain cardiac output, it can be dangerous to give these patients nitroglycerin, which is a potent vasodilator. Morphine can cause problems for the same reason.

. It's no accident that sinus bradycardia is the most common arrhythmia associated with inferior MI!

- EMS12lead.blogspot.com

Preload dependent yes it is a sexy catch phrase but is totally true. When you give nitro and MS, what are you trying to do? Decrease prelaod so that you can actually decrease afterload. I've said before, if you have a chest pain patient bradycardic (or borderline), hypotensive (absolute or realative), nitro is bad. This is the argument of why BLS giving nitro is a bad thing and especially ALS giving nitro without seeing the bigger picture. I've seen all too many protocols that say HR >60 bpm and SBP >100 as the cut off, which is too tight.

[FL_Medic]

I think the joke was that all human beings are "preload dependant". It's very understood what preload reduction will due to these patients. The are preload needy & on afterload overload. There's a new catch phrase for you.

+5 for new information. Didn't realize I'd been talking about "pre-load dependent" without thinking through what exactly NTG or MS will do to the patient systemically. Thanks for the great info and link!

- Matt

Edit: You're killing me FL_Medic. I hopped on here to take a break from a project and have spent the last half hour engrossed in that blog. I love the way he approaches topic on there, helps cement it way better than rereading my ECG book again. Highly recommend!

I was the same way when I first found that blog.

Edited April 24, 2009 by FL_Medic

[ERDoc]

Here is a brief, but chock full o' info presentation from ucsf

http://sfghed.ucsf.edu/Education/Lectures/Syllabus/EKG.pdf

[FL_Medic]

+5 for new information. Didn't realize I'd been talking about "pre-load dependent" without thinking through what exactly NTG or MS will do to the patient systemically. Thanks for the great info and link!

- Matt

Edit: You're killing me FL_Medic. I hopped on here to take a break from a project and have spent the last half hour engrossed in that blog. I love the way he approaches topic on there, helps cement it way better than rereading my ECG book again. Highly recommend!

also check out my strip teases on here.