The pericardium (from the Greek perikardion: perí meaning around, and kardia meaning heart) constitutes the envelope surrounding the heart.

Position. The heart is made up of a layer of muscle, the myocardium. This is enveloped by two distinct membranes: the endocardium, lining the internal surface, and the pericardium, covering the external surface (1).

Structure. The pericardium is made up of two structures (1) (2):

• The fibrous pericardium constitutes the outermost envelope. It is thick and composed of connective tissue of collagen, which helps prevent adhesion of the heart.
• The serous pericardium has two leaflets: a visceral lamina and a parietal lamina. The visceral lamina directly covers the outer surface of the heart, resulting in a smooth coating called the epicardium. The parietal lamina is closely related to the fibrous pericardium and is the source of a transudate. The latter is a liquid located between these two blades, forming the pericardial cavity.

Innervation. The pericardium receives sensitive, sympathetic and parasympathetic innervation. Sensory innervation is carried out by the pericardial branch of the phrenic nerve. Sympathetic innervation is carried out by the branches of the sympathetic trunk. Parasympathetic innervation passes through branches of the vagus nerve (2).

Secretion and reabsorption of transudate. The serous pericardium, and more particularly the parietal lamina, is the source of transudate secretion and reabsorption. The latter is a liquid involved in the sliding functions of the heart (2).

Heart sliding function. The pericardium allows the heart to slide during the contraction of the myocardium (2). This function is enabled thanks to the pericardial cavity, containing the transudate.

Maintenance of the myocardium. By surrounding the myocardium, the structure of the fibrous pericardium prevents distension of the latter (2).

Certain pathologies can affect the pericardium and cause chest pain.

Pericarditis. This pathology corresponds to inflammation of the pericardium. The causes can be varied but the origin is often a bacterial or viral infection. These inflammatory reactions can also cause fluid effusion leading to tamponade (2).

Pericardium tamponade. It corresponds to an accumulation of blood or fluid within the pericardium. This causes the heart to compress by the fluid, preventing the heart from functioning normally (2).

Surgical treatment. With a tamponade of the pericardium, surgery should be done quickly to remove the influx of fluid into the pericardium.

Medical treatment. Depending on the pathology diagnosed, drugs may be prescribed such as anti-inflammatory drugs.

Physical examination. First, a clinical examination is carried out in order to assess the pain perceived by the patient and to measure the heart rate.

Electrocardiogram. This test allows you to analyze the electrical activity of the heart.

Electrocardiogram effort. This test is used to analyze the electrical activity of the heart during physical exertion.

Medical imaging exam. In order to establish or confirm a diagnosis, a cardiac ultrasound, a Doppler ultrasound, a coronary angiography, a CT scan, a cardiac scintigraphy, or even an MRI can be performed.

20th century South African surgeon Christiaan Barnard is famous for performing the first successful heart transplant. In 1967, he transplanted a heart from a young woman who died in a car accident to a man with coronary artery disease. This patient will survive after the operation but will succumb to pneumonia 18 days later (3). Since this first successful transplant, medical progress has continued, as evidenced by recent experiments with transplants from an artificial heart.