ECG showing slight ST elevation in many leads congruent with pericarditis For<unk>  to formally be diagnosed, two or more of the following criteria must be present: chest pain consistent with a diagnosis of<unk>  (sharp chest pain worsened by breathing in or a cough), a pericardial friction rub, a pericardial effusion, and changes on electrocardiogram (ECG) consistent with<unk> . A complete blood count may show an elevated white count and a serum C-reactive protein may be elevated.<unk>  is associated with a modest increase in serum creatine kinase MB (CK-MB). and cardiac troponin I (cTnI), both of which are also markers for injury to the muscular layer of the heart. Therefore, it is imperative to also rule out acute myocardial infarction in the face of these biomarkers. The elevation of these substances may occur when inflammation of the heart's muscular layer in addition to<unk> . Also, ST elevation on EKG (see below) is more common in those patients with a cTnI > 1.5 µg/L. Coronary angiography in those patients should indicate normal vascular perfusion. Troponin levels increase in 35-50% of people with pericarditis. Electrocardiogram (ECG) changes in<unk>  mainly indicates inflammation of the epicardium (the layer directly surrounding the heart), since the fibrous pericardium is electrically inert. For example, in uremia, there is no inflammation in the epicardium, only fibrin deposition, and therefore the EKG in uremic pericarditis will be normal. Typical EKG changes in<unk>  includes * stage 1 -- diffuse, positive, ST elevations with reciprocal ST depression in aVR and V1. Elevation of PR segment in aVR and depression of PR in other leads especially left heart V5, V6 leads indicates atrial injury. * stage 2 -- normalization of ST and PR deviations * stage 3 -- diffuse T wave inversions (may not be present in all patients) * stage 4 -- EKG becomes normal OR T waves may be indefinitely inverted The two most common clinical conditions where ECG findings may mimic pericarditis are acute myocardial infarction (AMI) and generalized early repolarization. As opposed to pericarditis, AMI usually causes localized convex ST-elevation usually associated with reciprocal ST-depression which may also be frequently accompanied by Q-waves, T-wave inversions (while ST is still elevated unlike pericarditis), arrhythmias and conduction abnormalities. In AMI, PR-depressions are rarely present. Early repolarization usually occurs in young males (age <40 years) and ECG changes are characterized by terminal R-S slurring, temporal stability of ST-deviations and J-height/ T-amplitude ratio in V5 and V6 of <25% as opposed to pericarditis where terminal R-S slurring is very uncommon and J-height/ T-amplitude ratio is ≥ 25%. Very rarely, ECG changes in hypothermia may mimic pericarditis, however differentiation can be helpful by a detailed history and presence of an Osborne wave in hypothermia. Another important diagnostic electrocardiographic sign in<unk>  is the Spodick sign. It signifies to the PR-depressions in a usual (but not always) association with downsloping TP segment in patients with<unk>  and is present in up to 80% of the patients affected with<unk> . The sign is often best visualized in lead II and lateral precordial leads. In addition, Spodick's sign may also serve as an important distinguishing electrocardiographic tool between the<unk>  and acute coronary syndrome. The presence of a classical Spodick's sign is often a giveaway to the diagnosis. Rarely, electrical alternans may be seen, depending on the size of the effusion. A chest x-ray is usually normal in<unk>  but can reveal the presence of an enlarged heart if a pericardial effusion is present and is greater than 200 mL in volume. Conversely, patients with unexplained new onset cardiomegaly should always be worked up for<unk> . An echocardiogram is typically normal in<unk>  but can reveal pericardial effusion, the presence of which supports the diagnosis, although its absence does not exclude the diagnosis.
Acute pericarditis
Myocardial stunning
Wooden chest syndrome
Uremic pericarditis
Acute coronary syndrome
Acute chest syndrome
Constrictive pericarditis
Unstable angina