Tuesday, July 29, 2008

Day #29 - Demand Ischemia

Today we talked about a case of a young man who essentially presented with status epilepticus and was found to have some non-specific ECG changes, a CXR compatible with CHF though without evidence of CHF on clinical exam, and an elevated cardiac troponin.

The discussent, a cardiologist, facilitated a good discussion on the approach to a patient with seizures including considering that what was labelled "seizure" may, in some patients with underlying cardiac dysrthmias or ischemic/structural heart disease be a presentation of primary cardiac abnormalities.

In this patient, who subsequently turned out to have a normal baseline ECG and a normal 2D echo and who will go on to angiography, the suspicion is that this troponin increase was caused by severe myocardial demand during the status epilepticus. The combination of catecholamine surge, increased muscle tone leading to increased afterload, and tachycardia presumably led to sub-endocardial ischemia.

There are conflicting case reports about whether seizures themselves can lead to troponin increases with one small patient series saying no, and several single patient case reports saying yes. I think the take home message from this is that you can't write off significantly elevated troponins as being entirely due to the seizure.

We spent some time discussing stress-induced cardiomyopathy or apical ballooning syndrome. There are some case reports of status epilepticus causing this syndrome (in one of these cases the troponin was elevated to 10!).

Also, if you haven't done so already, I would suggest you review the blog on seizures/status epilepticus.

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