Traumatic aortic rupture, also called traumatic aortic disruption or transection, is a condition in which the
aorta
The aorta ( ) is the main and largest artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen, where it splits into two smaller arteries (the common iliac arteries). The aorta distributes ...
, the largest
artery
An artery (plural arteries) () is a blood vessel in humans and most animals that takes blood away from the heart to one or more parts of the body (tissues, lungs, brain etc.). Most arteries carry oxygenated blood; the two exceptions are the pul ...
in the body, is torn or ruptured as a result of trauma to the body. The condition is frequently fatal due to the profuse
bleeding
Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vag ...
that results from the rupture. Since the aorta branches directly from the
heart
The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide t ...
to supply
blood
Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood in the c ...
to the rest of the body, the pressure within it is very great, and blood may be pumped out of a tear in the blood vessel very rapidly. This can quickly result in
shock
Shock may refer to:
Common uses Collective noun
*Shock, a historic commercial term for a group of 60, see English numerals#Special names
* Stook, or shock of grain, stacked sheaves
Healthcare
* Shock (circulatory), circulatory medical emergen ...
and death. Thus traumatic aortic rupture is a common killer in
automotive accidents and other traumas,
with up to 18% of deaths that occur in automobile collisions being related to the injury.
In fact, aortic disruption due to blunt
chest trauma
A chest injury, also known as chest trauma, is any form of physical injury to the chest including the ribs, heart and lungs. Chest injuries account for 25% of all deaths from traumatic injury. Typically chest injuries are caused by blunt mechanism ...
is the second leading cause of injury death behind
traumatic brain injury
A traumatic brain injury (TBI), also known as an intracranial injury, is an injury to the brain caused by an external force. TBI can be classified based on severity (ranging from mild traumatic brain injury TBI/concussionto severe traumatic b ...
.
Aortic rupture
Aortic rupture is the rupture or breakage of the aorta, the largest artery in the body. Aortic rupture is a rare, extremely dangerous condition. The most common cause is an abdominal aortic aneurysm that has ruptured spontaneously. Aortic rupture ...
can also be caused by non-traumatic mechanisms, particularly
abdominal aortic aneurysm
Abdominal aortic aneurysm (AAA) is a localized enlargement of the abdominal aorta such that the diameter is greater than 3 cm or more than 50% larger than normal. They usually cause no symptoms, except during rupture. Occasionally, abdominal, ...
rupture.
Symptoms and signs
Symptoms are often unreliable, but include severe tearing chest pain; cough;
dyspnea
Shortness of breath (SOB), also medically known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathing, breathe well enough. The American Thoracic Society defines it as "a subjective experience of brea ...
(shortness of breath);
dysphagia
Dysphagia is difficulty in swallowing. Although classified under "symptoms and signs" in ICD-10, in some contexts it is classified as a disease#Terminology, condition in its own right.
It may be a sensation that suggests difficulty in the passag ...
(difficulty swallowing); back pain; and hoarseness. Blood pressure is usually high in the upper body, but low in the lower body. A widened
mediastinum
The mediastinum (from ) is the central compartment of the thoracic cavity. Surrounded by loose connective tissue, it is an undelineated region that contains a group of structures within the thorax, namely the heart and its vessels, the esophagu ...
and a massive left
hemothorax
A hemothorax (derived from hemo- lood+ thorax hest plural ''hemothoraces'') is an accumulation of blood within the pleural cavity. The symptoms of a hemothorax may include chest pain and difficulty breathing, while the clinical signs may incl ...
are often found in an X-ray. There can be bruising of the anterior chest wall, and a
systolic murmur
Systolic heart murmurs are heart murmurs heard during systole, i.e. they begin and end between S1 and S2. Many involve stenosis of the semilunar valves or regurgitation of the atrioventricular valves.
Types
* Mid-systolic ejection murmurs are ...
can be heard on the bottom of the heart.
Causes
The injury is usually caused by high speed impacts such as those that occur in vehicle collisions and serious falls.
It may be due to different rates of deceleration of the heart and the aorta, which is in a fixed position.
Location of rupture
By far the most common site for tearing in traumatic aortic rupture is the
proximal descending aorta, near where the left
subclavian artery branches off from the aorta. The tethering of the aorta by the
ligamentum arteriosum
The ligamentum arteriosum (arterial ligament), also known as the Ligament of Botallo or Harvey's ligament, is a small ligament attaching the aorta to the pulmonary artery. It serves no function in adults but is the remnant of the ductus arteriosus ...
makes the site prone to shearing forces during sudden deceleration.
[
A study of people who died after traumatic aortic rupture found that in 55–65% of cases the damage was at the aortic isthmus and in 10–14% it was in the ascending aorta or ]aortic arch
The aortic arch, arch of the aorta, or transverse aortic arch () is the part of the aorta between the ascending and descending aorta. The arch travels backward, so that it ultimately runs to the left of the trachea.
Structure
The aorta begins a ...
. An angiogram will often show an irregular outpouching beyond the takeoff of the left subclavian artery at the aortic isthmus, representing an aortic pseudoaneurysm
A pseudoaneurysm, also known as a false aneurysm, is a locally contained hematoma outside an artery or heart due to damage to the vessel wall. The injury goes through all the three layers of the arterial wall causing a leak, which is contained b ...
caused by the trauma. Damage can also be in the lower thoracic or abdominal aorta.
Pathology
The aorta is not always torn completely through; it may also tear some but not all layers of the arterial wall, sometimes forming a false aneurysm
A pseudoaneurysm, also known as a false aneurysm, is a locally contained hematoma outside an artery or heart due to damage to the vessel wall. The injury goes through all the three layers of the arterial wall causing a leak, which is contained ...
. A sub-intima
The tunica intima (New Latin "inner coat"), or intima for short, is the innermost tunica (layer) of an artery or vein. It is made up of one layer of endothelial cells and is supported by an internal elastic lamina. The endothelial cells are in ...
l hemorrhage is the least serious type.
Intimal tear
Being the mildest form, it often does not weaken the wall of the aorta and may heal on its own. Usually, it occurs in the descending aorta
In human anatomy, the descending aorta is part of the aorta, the largest artery in the body. The descending aorta begins at the aortic arch and runs down through the chest and abdomen. The descending aorta anatomically consists of two portions o ...
. It was originally defined as a small intimal flap with less than one centimeter length and with little or no haematoma. It is 10-28% of aortic injuries.
Diagnosis
The condition is difficult to detect and may go unnoticed, because many patients have no specific symptoms. Diagnosis is further complicated by the fact that many patients with the injury experienced multiple other serious injuries as well, so the attention of hospital staff may be distracted from the possibility of aortic rupture. In fact most cases occur along with other injuries.
A common symptom is unusually high blood pressure in the upper body and very low blood pressure in lower limbs. Another sign is kidney failure
Kidney failure, also known as end-stage kidney disease, is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney failure is classified as eit ...
where the creatinine
Creatinine (; ) is a breakdown product of creatine phosphate from muscle and protein metabolism. It is released at a constant rate by the body (depending on muscle mass).
Biological relevance
Serum creatinine (a blood measurement) is an importa ...
level shoots very high and urine output becomes negligible. In most cases, however, the doctors would misinterpret kidney failure as due to issues with the kidney itself and may recommend dialysis.
Though not completely reliable, chest X-ray
An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...
s are the first-line investigation, initially used to diagnose this condition when the patient is unstable and cannot be sent to the CT bay. The preferred method of diagnosis used to be CT angiogram
Computed tomography angiography (also called CT angiography or CTA) is a computed tomography technique used for angiography—the visualization of arteries and veins—throughout the human body. Using contrast injected into the blood vessels, i ...
until it was found to cause complications in some people; now it is reserved for when CT scans are inconclusive.
The classical findings on a chest X-ray will be widened mediastinum, apical cap, and displacement of the trachea, left main bronchus, or nasogastric tube. A normal chest x-ray does not exclude transection, but will diagnose conditions such as pneumothorax or hydrothorax. The aorta may also be torn at the point where it is connected to the heart. The aorta may be completely torn away from the heart, but patients with such injuries rarely survive very long after the injury; thus it is much more common for hospital staff to treat patients with partially torn aortas. When the aorta is partially torn, it may form a "pseudoaneurysm". In patients who do live long enough to be seen in a hospital, a majority have only a partially torn blood vessel, with the outermost adventitial
The adventitia () is the outer layer of fibrous connective tissue surrounding an organ.
The outer layer of connective tissue that surrounds an artery, or vein – the tunica externa, is also called the ''tunica adventitia''.
To some degree, it ...
layer still intact. In some of these patients, the adventitia and nearby structures within the chest may serve to prevent severe bleeding
Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vag ...
. After trauma, the aorta can be assessed by a CT angiogram or a direct angiogram, in which contrast is introduced into the aorta via a catheter.
Treatment
Aortic transection
Traumatic aortic rupture is treated with surgery. However, morbidity
A disease is a particular abnormal condition that negatively affects the structure or function of all or part of an organism, and that is not immediately due to any external injury. Diseases are often known to be medical conditions that a ...
and mortality rate
Mortality rate, or death rate, is a measure of the number of deaths (in general, or due to a specific cause) in a particular population, scaled to the size of that population, per unit of time. Mortality rate is typically expressed in units of de ...
s for surgical repair of the aorta for this condition are among the highest of any cardiovascular surgery. For example, surgery is associated with a high rate of paraplegia
Paraplegia, or paraparesis, is an impairment in motor or sensory function of the lower extremities. The word comes from Ionic Greek ()
"half-stricken". It is usually caused by spinal cord injury or a congenital condition that affects the neural ...
, because the spinal cord
The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spi ...
is very sensitive to ischemia
Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems wi ...
(lack of blood supply), and the nerve tissue can be damaged or killed by the interruption of the blood supply during surgery.
A less invasive option for treatment is endovascular repair, which does not require open thoracotomy
A thoracotomy is a surgical procedure to gain access into the pleural space of the chest. It is performed by surgeons (emergency physicians or paramedics under certain circumstances) to gain access to the thoracic organs, most commonly the hea ...
and can be safer for people with other injuries to organs.
Since high blood pressure
Blood pressure (BP) is the pressure of circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term "blood pressure" r ...
could exacerbate an incomplete tear in the aorta or even separate it completely from the heart, which would almost inevitably kill the patient, hospital staff take measures to keep the blood pressure low. Such measures include giving pain medication
An analgesic drug, also called simply an analgesic (American English), analgaesic (British English), pain reliever, or painkiller, is any member of the group of drugs used to achieve relief from pain (that is, analgesia or pain management). It ...
, keeping the patient calm, and avoiding procedures that could cause gagging or vomiting
Vomiting (also known as emesis and throwing up) is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the Human nose, nose.
Vomiting can be the result of ailments like Food-poisoning, foo ...
. Beta blocker
Beta blockers, also spelled β-blockers, are a class of medications that are predominantly used to manage cardiac arrhythmia, abnormal heart rhythms, and to protect the heart from a second myocardial infarction, heart attack after a first heart ...
s and vasodilators can be given to lower the blood pressure, and intravenous fluids that might normally be given are foregone to avoid raising it.
In 1959, Passaro reported the first successful surgical repair of a torn aorta. Kirsh, in 1976, reported a 70% success rate in surgery to repair a torn aorta, based on 10 years of experience as a surgeon. Therefore, for those who make it to the hospital (85% do not), are successfully diagnosed in time and are quickly operated upon, the chances of survival are higher.
Intimal tear
In some cases, intimal tears may resolve on their own. Therefore, conservative treatment like antihypertensives are usually initiated. There is limited data on the treatment of this type of aortic injury. In some places, endovascular repair is also an option for treatment.
Prognosis
Death occurs immediately after traumatic rupture of the thoracic aorta 75%–90% of the time since bleeding is so severe, and 80–85% of patients die before arriving at a hospital. Of those who live to reach a hospital, 23% die at the time of or shortly after arrival. In the US, an estimated 7,500–8,000 cases occur yearly, of which 1,000–1,500 make it to a hospital alive; these low numbers make it difficult to estimate the efficacy of surgical options. However, if surgery is performed in time, it can offer a chance of survival.
Though there is a concern that a small, stable tear in the aorta could enlarge and cause complete rupture of the aorta and heavy bleeding, this may be less common than previously believed as long as the blood pressure does not get too high.
There have been five rare cases of a traumatic aortic rupture going undiagnosed of more than a year, and presenting with chest and back pain. They had pseudoaneurysm
A pseudoaneurysm, also known as a false aneurysm, is a locally contained hematoma outside an artery or heart due to damage to the vessel wall. The injury goes through all the three layers of the arterial wall causing a leak, which is contained b ...
s or large aneurysms that caused pain. Asymptomatic chronic traumatic aneurysms are not always a risk for sudden death unless too large. Growing aneurysms, symptomatic or not, have a risk of rupture so the treatment is surgical removal.
See also
* Chest trauma
A chest injury, also known as chest trauma, is any form of physical injury to the chest including the ribs, heart and lungs. Chest injuries account for 25% of all deaths from traumatic injury. Typically chest injuries are caused by blunt mechanism ...
* Aortic dissection
Aortic dissection (AD) occurs when an injury to the innermost layer of the aorta allows blood to flow between the layers of the aortic wall, forcing the layers apart. In most cases, this is associated with a sudden onset of severe chest or ...
* Pulmonary contusion
A pulmonary contusion, also known as lung contusion, is a bruise of the lung, caused by chest trauma. As a result of damage to capillaries, blood and other fluids accumulate in the lung tissue. The excess fluid interferes with gas exchange, po ...
References
External links
{{DEFAULTSORT:Traumatic Aortic Rupture
Diseases of the aorta
Chest trauma
Injuries of abdomen, lower back, lumbar spine and pelvis