AssessmentsPericarditis and pericardial effusion
Pericarditis and pericardial effusion
USMLE® Step 1 style questions USMLE
USMLE® Step 2 style questions USMLE
A 44-year-old man comes to the emergency department because of sudden chest pain and difficulty breathing for the past three hours. The pain is felt in the retrosternal area and radiates up to his left shoulder and arm; it worsens on inspiration and is relieved when leaning forward. Physical examination shows no abnormalities. Pericardial friction rub is heard on auscultation. Laboratory results show elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels. An ECG is taken and shown below. Which of the following is the most likely diagnosis?
With pericarditis, “peri” means “around,” card means “the heart”, and itis means “inflamed”. So pericarditis means the pericardial layer of tissue that covers the heart has inflammation. Acute pericarditis generally lasts just a few weeks, whereas chronic pericarditis lasts longer, usually more than 6 months. People who develop pericarditis are also at risk of also developing a pericardial effusion - that’s when the inflammation causes fluid to accumulate around the heart.
The pericardium is a pouch or cavity that the heart sits inside of. The outer layer of this pouch is the fibrous pericardium and it helps keep the heart in place within the chest cavity. The inner layer of the pouch is the serous pericardium that includes the pericardial cavity, and is filled with a small amount of fluid that lets the heart slip around as it beats. The cells of the serous pericardium secrete and reabsorb the fluid, so usually there’s no more than 50 milliliters of fluid in the pericardial cavity at one time - that’s about as much as a shot glass.
Now, the cause of acute pericarditis is usually idiopathic, meaning that we don’t know what causes it. When the cause is identified, it’s usually a viral infection, like Coxsackie B virus. Another cause is Dressler syndrome which occurs several weeks after a