Causes and risk factors
Exact cause of aortic dissection is yet unknown. But high chronic blood pressure is the leading cause of aortic dissection. Other causes are coarctation of aorta, aortic aneurysm, and atherosclerosis. Congenital diseases like bicuspid aortic valve, marfan’s syndrome, Turner’s syndrome, Ehlers-Danlos syndrome also contribute to cause aortic dissection. Other risk factors such as connective tissue disorders, pregnancy, post cardiac surgery may be responsible for developing aortic dissection. Direct Trauma to the chest is a rare but possible cause of aortic dissection.
Clinical presentation
Aortic dissection can occur as TYPE A – dissection in upper [ascending aorta] or TYPE B – dissection in lower [descending] aorta. Patient with acute aortic dissection presents with onset of severe chest pain. Location of the pain may reveal the site of dissection. Anterior chest pain occurs in dissection of anterior arch or anterior root. Pain in the neck, jaw indicates dissection in arch of aorta extending to great vessels. Tearing, gripping pain in the intracapsular area suggests dissection in descending aorta. It is painless in about 10% of patients. Signs of aortic dissection involve Blood pressure difference in two arms, bulging neck veins, cardiac murmur on auscultation. Further signs involve neurological deficits such as syncope. Cerebrovascular accidents showing signs of hemianaesthesia, hemiplegia. Cardiovascular manifestations involve signs of CCF such as dyspnoea, orthopnoea. Respiratory signs such as haemoptysis or signs of haemothorax may occur if the dissection ruptures into pleura. Other clinical features include disorientation, anxiety, dysphagia, flank pain, abdominal pain, dryness of mouth and skin, increased thirst, nausea, vomiting, profuse sweating, rapid weak pulse, and signs of shock.
Investigation
Medical history by the patient and Clinical examination by the doctor helps in diagnosis. An ECG, chest x-ray, transoesophageal echocardiogram [ TEE], USG Doppler, CT,MRI scan of chest, aortic angiography are some of the necessary investigation procedures.
Treatment
Treatment includes surgery which involves removal of damaged aortic portion and reconstruction of aorta with help of grafts. Medications are given such as beta blockers to prevent worsening of aortic dissection. Another surgery includes repair of aorta with use of stents placed in the aorta which provides a frame to the aorta preventing it from dissecting. Anti hypertensive medicines are prescribed post surgery.
