Dr.S.Venkatesan MD

Heart has three layers

• Epicardium
• Myocardium
• Endocardium

Epicardium is same as visceral pericardium . If pericardial inflammation dissusely occurs ,  it is bound to injure  the epicardium and subepicardium .

Does  the  troponins  located deep inside the  myocardium  ?

No .It  can  even be present just few microns below the visceral pericardium  . Hence  severe forms of pericarditis can elevate the troponin levels without any issues .

Is troponin  release related to ST elevation ?

 Ideally  most forms of  pericarditis can be termed as epicarditis. The mechanism of ST elvation in pericarditis is actually a sign of  epicardial injury.In fact ,  there is no easy way to  differentiate  a  slice of epicardial infarct from an   inflammatory pericarditis accurately .

Is there any form of pericarditis which invlove only parietal pericardium ?

We do not know as yet ,  about  existance of such  an entity. It is distinctly possible. However , if present it is unlikely to result in significant  ST elevation in ECG.

In pericarditis ,  troponin release is due to inflammation  or necrosis  ?

Both are possible .Even transient wall motion defects are reported in isolated pericarditis.

What is myopericarditis ?

It is  a general term used  to indicate the above situation . In practical terms Pericarditis + Troponin positivity can be termed as myopericardits. It is well known pericardits can extend to endo- myocardium but it is rare other way  around( ie endocarditis extending to pericardium )

What is pancarditis ?

It is the carditis  involving all three layers of heart ,Cassically occura in rheumatic fever. Fulminant carditis is known to raise the troponin to significant levels.

Does troponin elevation  in pericarditis  occur in all  ?

We are yet to collect adequate data about this .  Diffuse , extensive pericarditis ,gross ST elevation ,  and associated pericardial effusion  correlate with troponin.

Crazy questions in pericardiology

What is the pericardial blood supply ? Is there  an entity called ischemic pericarditis ?

Final message

Do not ever underestimate the  importance of  pericardium  whenever you encounter unexplained ST elevation in ECG.

Reference

Here is an article which has   meticulously studied this issue