Modern biological artificial heart valves available for clinical use, with the exception of pulmonary autograft, are non-viable structures that lack the potential for growth and tissue reparation. This imposes significant limitations on their use, especially in children, for the correction of valve pathology.

Shoulder arthritis is an inflammatory condition that affects the joint in the shoulder area.

Arthritis of the laryngeal joints occurs primarily and secondarily. Primary arthritis is caused by rheumatoid infection and manifests itself along with damage to other joints - hands, feet, less often larger joints (rheumatoid and rheumatic polyarthritis).

Arthralgia is a syndrome accompanied by pain and dysfunction of a joint or group of joints. Arthralgia is observed not only in diseases of the articular apparatus (arthritis, arthrosis, diseases of periarticular tissues), but also in other pathological processes: infectious-allergic processes, diseases of the blood, nervous and endocrine systems, etc.

An arteriovenous fistula is an abnormal connection between an artery and a vein. An arteriovenous fistula may be congenital (usually in the area of small vessels) or acquired as a result of trauma (such as a bullet or stab wound) or erosion of an arterial aneurysm into an adjacent vein.

Arterial hypotension is a symptom that reflects various degrees of decreased arterial pressure. It should be emphasized that the term hypotension (from the Greek hypo - little and Latin tensio - tension) more accurately denotes decreased arterial pressure. According to modern concepts, the term "tonia" should be used to describe muscle tone, including smooth muscles of the vascular wall, the term "tension" - to denote the magnitude of fluid pressure in vessels and cavities.

Arterial hypertension is a condition in which the systolic blood pressure level is equal to or exceeds 140 mmHg and/or the diastolic blood pressure level is equal to or exceeds 90 mmHg at 3 different blood pressure measurements.

An aneurysm is a local widening of the lumen of an artery as a result of changes or damage to its walls. Most often, brain aneurysms are a disease of the arterial triads of the polygon of Willis.

Acidum arsenicosum is used in dentistry to treat inflamed pulp. It is a sympathicotropic poison that affects the smallest blood vessels, they rupture, as a result - the nutrition of the pulp tissue is disrupted and it becomes necrotic. Arsenic periodontitis is a consequence of incorrect treatment of acute pulpitis.