Aortic Dissection: Types, Causes, Symptoms, Treatment, Survival Rate, Prognosis, Complications, Epidemiology
A vast majority of the population is known to suffer from one type of heart disease or the other. While heart diseases were typically related to old age even a few years back, the perception has undergone quite a change in the recent years with the younger section of the population also falling prey to the disease. Among many of the heart-related diseases on the block, Aortic Dissection is one which manifests symptoms similar to other heart diseases but needs special medical attention.
What is Aortic Dissection and How Does it Happen?
The aorta refers to the large blood vessel that is responsible for carrying blood outside the heart. The rupturing of the internal layer of this blood vessel or aorta leads to a critical condition in people wherein the blood surges through the rupture leading to the separation or dissection of the inner and middle layers of the aorta. Aortic dissection can often lead to reduced blood flow to other organs of the body due to the blood flow in between the layers of the aorta. Affecting people, especially men in their sixties and seventies, aortic dissection can prove to be a fatal one if the channel filled with blood tears through the external aortic wall.
What are the Symptoms of Aortic Dissection?
In a majority of the cases of Aortic Dissection, the symptoms manifest themselves suddenly and are very much similar to other heart issues. However, there are certain signs and symptoms that one could look out for-
- A person suffering from aortic dissection may experience symptoms of a sudden sharp tearing pain that arises in the chest or upper back portion of the body radiating down to the neck.
- Shortness of breath often accompanied by loss of consciousness can also be observed in such cases.
- Patients suffering from aortic dissection may experience symptoms of sudden difficulty in speech, vision with a feeling of weakness accompanied by paralysis of one side of the body.
- Patients might also feel a weak pulse in one arm as compared to the other.
Since, there occurs a reduction in the flow of blood to the other organs of the body, patients with aortic dissection may also manifest certain other symptoms such as:-
- A clammy feeling or sweating heavily with pale skin accompanied by fainting spells or dizziness.
- The patients with aortic dissection may also go through nausea followed by vomiting along with abdominal pain.
- Patients may also face problem due to the pressure on the esophagus.
Types of Aortic Dissection
Based on the location of the rupture, Aortic Dissection may be divided into two groups, viz,-
- Aortic Dissection Type A: Initiating in the ascending aorta and progressing throughout the vessel, this type of Aortic Dissection is found to extend as far as the arteries of the leg. This type of the disease calls for immediate surgery so as to prevent death from bleeding, stroke, heart attack or congestive heart failure.
- Aortic Dissection Type B: Though the tear in this type is initially located in the descending aorta, it is not unlikely for the tear to extend into the abdomen. This condition can be generally handled by the extensive control of blood pressure with the additional treatments depending on the complications that might occur from the tear.
Classification of Aortic Dissection
There are two standard ways in which one could look at the classification of Aortic Dissection, viz, the Stanford classification and the DeBakey classification.
- Stanford Classification: The Stanford Classification divides Aortic Dissection into two groups, viz, Type A and Type B based on the involvement of the ascending aorta.
- Type A Aortic Dissection: The ascending aorta along with the aortic arch is included in the Type A Aortic Dissection, wherein the tear occurring either in the aortic arch or ascending aorta and rarely in the descending aorta. The DeBakey Types I and Type II Aortic Dissection are also included in this type.
- Type B Aortic Dissection: This type of Aortic Dissection occurs when there is involvement of the descending aorta or arc that is away from the left subclavian artery without incorporating the ascending aorta. The Type III of the DeBakey Aortic Dissection classification is included here.
- DeBakey Classification: The DeBakey system classifies Aortic Dissection based on the extent and the location of the dissection.
- Type I Aortic Dissection: Most frequently seen in people less than 65 years of age, this type of Aortic Dissection involves the ascending aorta and propagates to the aortic arch and beyond it distally.
- Type II Aortic Dissection: The Type II of the Aortic Dissection, as per the DeBakey classification, has its origin in the ascending aorta and remains typically confined to it.
- Type III Aortic Dissection: The Type III of the Aortic Dissection originates in the descending aorta, rarely extending proximally but frequently doing so distally. This type of the disease is more likely to affect patients with a record of hypertension and atherosclerosis.
What are the Causes and Risk Factors of Aortic Dissection?
Aortic Dissection is likely to occur in the weakened area of the wall of the aorta. There are a number of factors that could be seen as the causative factors for aortic dissection-
- High blood pressure results in stressing of the aortic tissue leading to high chances of it rupturing.
- Certain people are born with conditions such as an enlarged and weakened aorta, such as, the bicuspid aortic valve or Marfan syndrome, which also contribute in increasing the chances of the development of tear in the aortic wall.
- Atherosclerosis or the condition where the arteries are hardened, Aortic Coarctation or the narrowing of the aorta at the time of birth may also be seen as causative factors of Aortic Dissection.
- Though rare, traumatic injuries, pregnancy, heart surgeries and the like are also known to be causative factor behind the rupture of the aortic wall, leading to Aortic Dissection.
- Certain genetic diseases such as Turner's syndrome, Connective Tissue Disorder, Marfan Disorder and certain other infectious conditions such as, inflammation of the arteries, syphilis and sexually transmitted diseases also add to the risk factors of Aortic Dissection.
Certain other risk factors may also contribute to increased chances of Aortic Dissection such as:
- Aging: People, aged between 60 and 80, have higher chances of suffering from aortic dissection than people of other ages.
- Use of Cocaine: Cocaine is known for increasing blood pressure temporarily, thereby increasing the chances of Aortic Dissection.
- Strenuous physical activities such as, weight lifting and the like may also increase the chances of the occurrence of aortic dissection.
Complications of Aortic Dissection
Since Aortic Dissection is characterized by the reduced flow of blood to the other organs of the body, these organs may develop certain long term or short term issues and suffer from a certain degree of damage. The organs at maximum risk are the heart, brain, kidneys, intestines and legs.
There are certain other complications that have high probability of occurrence due to Aortic Dissection, viz,-
- Damage to the organs, such as kidney failure, damaging of the intestines and the like.
- Severe internal bleeding may also lead to the death of patients with aortic dissection.
- Patients with aortic dissection are also at a high risk of stroke.
- Cardiac tamponade or the lining around the heart may also get ruptured and damaged along with damage to the aortic valve.
Prognosis and Survival Rate of Aortic Dissection
Aortic Dissection is one of the many diseases with life threatening consequences. Though the condition can be improved via surgery, it needs to be carried out before the aorta ruptures. Statistics show that less than fifty percent people suffering from ruptured aorta survive. Patients also need to undergo extensive treatment and careful monitoring of the aorta with frequent CT Scans in order to lead a healthy life.
Around 20% of the patients suffering from Aortic Dissection die before they can reach the hospital while the mortality rate for the first twenty four hours before treatment is 1 to 3% per hour. The hospital mortality rate among patients suffering from proximal Aortic Dissection is 30% while those suffering from Distal Aortic Dissection are about 10%.
Epidemiology of Aortic Dissection
Aortic Dissection is often misdiagnosed at the first instance, with the real cause often surfacing after the death of the patients. The disease is said to affect approximately 2-3.5 people out of every one lakh people. Around 65% of the patients suffering from Aortic Dissection are reported to be male around the age of 63-65 years. The disease is most likely to occur in females after the postpartum period. Studies from Sweden have also suggested the rise of the people suffering from the disease.
Diagnosis of Aortic Dissection
As the symptoms manifested by Aortic Dissection are confused with other heart diseases, it is important to undergo proper diagnostic procedure in order to avail proper treatment. Some of the tests that the physician might conduct are-
- Aortic angiography
- Doppler ultrasonography
- CT Scan of chest
- Chest X-ray and MRI
- Transesophageal Echocardiogram
- Tests to rule out the possibility of heart attack are also likely to be conducted.
The medical practitioner is also likely to look out for certain signs whilst examination, viz,-
- Low blood pressure
- Dissimilarity in the blood pressure of the limbs.
- Normal blood pressure accompanied by symptoms of shock.
What is the Treatment of Aortic Dissection?
A life-threatening and critical condition, Aortic Dissection needs proper treatment and care immediately.
- Ruptures or tear occurring in the ascending aorta or the aorta that branches off the heart needs to be treated with immediate surgery while dissection occurring in the descending aorta is treated with extensive medicine as well as surgery.
- The process of surgery in order to fix Aortic Dissection generally includes two techniques, viz-
- Endovascular aortic repair done without the use of any major surgical incisions and
- Standard open surgery which requires a surgical incision in the abdomen or chest.
- Drugs that reduce the blood pressure extensively and beta-blockers may also be prescribed with the administration being intravenous in some cases. Physicians may also suggest strong pain-killers as well.
- Involvement of a damaged aortic valve also gives rise to the need of valve replacement surgery and a coronary bypass surgery is also conducted in case of the involvement of arteries.
Lifestyle and Coping with Aortic Dissection
It is imperative for patients to bring about certain lifestyle changes post Aortic Dissection in order to live a full and proper life.
- Strenuous physical activities, such as, weight lifting, should be avoided as they increase the blood pressure drastically and strain the aortic wall greatly.
- People should resort to mild aerobic exercises and avoid all forms of contact sports.
- People with jobs requiring them to be physically active need to change their jobs post Aortic Dissection as sedentary jobs are best suited for such patients.
- Lifestyle modifications need to be thoroughly discussed with the health-care provider before the implementation.
Though Aortic Dissection wreaks havoc on the lives of the patients, certain lifestyle modifications can go a long way in ensuring a full life for the patients. As the symptoms manifested by the disease are quite similar to other heart diseases, it is therefore, important for patients to get properly diagnosed before opting for any treatment.