RUPTURE THORACIC AORTIC DISSECTION

What is Aortic Dissection?

In aortic dissection, a tear occurs in the wall of the aorta. This causes bleeding into and along the aortic wall and, in some cases, completely outside the aorta (rupture). The process of aortic dissection is dynamic and can occur anywhere along the course of the aorta, resulting in a wide spectrum of clinical manifestations. The presence of an “intimal flap,” representing the intimomedial septum between true and false lumina, is the most characteristic pathology in acute aortic dissection. The origin of the intimal flap/tear is in the ascending aorta in 65%, the descending aorta in 25%, and in the arch and abdominal aorta in 10% of patients. The pathognomonic lesion is one of an intimal tear followed by blood surging either antegrade (typically) or retrograde (depending on the hemodynamic gradient between the true and false lumina) and cleaving the intima and media layers of the aortic wall longitudinally for a variable distance.  Fenestrations (connections between the true and false lumina) occur within the intimal flap downstream, usually at branch vessel ostia, which are cleaved by the dissection process. These serve as sites of reentry of blood flow into the true lumen, thus maintaining false lumen patency.

What is Main Cause of Aortic Dissection?

Factors that predispose one to development of aortic dissection include age, hypertension, and structural abnormalities of the aortic wall. Men are more frequently affected with a male-to-female ratio of 4 : 1 and  type A dissections(Origin of Intimal tear in Ascending Aorta) account for 60% of cases.  The incidence of type A dissection peaks between 50 and 60 years, whereas type B dissections occur more frequently between 60 and 70 years of age.11 Hypertension is the rule and was present in 70% of patients Risk Factors for Dissection. Bicuspid Aortic Valve, Coarctation of Aorta, Marfan’s Syndrome, Pregnancy, Artherosclerosis, Cystic Medial Necrosis are high risk factors for Aortic dissection  Cardiovascular conditions, such as acute myocardial infarction and sudden death, have been shown to demonstrate certain chronobiologic patterns of occurrence and the same is true of acute aortic dissection. The onset of dissection occurs most frequently in the morning hours, between 6 AM and 12 PM, and more often in the winter (28%) than the Summer.

What Happens When Aortic Dissection Ruptures?

About 40% of patients die immediately from complete rupture and bleeding out from the aorta.

What are the signs of Ruptured Aortic Dissection and Acute Aortic Dissection?

Sudden, intense and persistent chest or back pain. The most common presenting symptom of acute aortic dissection is pain (located in the back, abdomen, or chest), of abrupt onset. Typically described as anterior in location in type A dissections but is more often experienced in the back in type B dissections . Although the classic description of pain associated with aortic dissection is ripping or tearing (50%), patients more frequently complain of sharp, stabbing pain (68%) and less often experience migratory symptoms. Typically, the pain is severe, causing the patient to seek medical attention within minutes to hours of onset, and has been described as “the worst ever” by nearly

  • Syncope(Loss of consciousness)
  • Neurologic Symptoms(Spinal cord Ischemia,Paraesthesia,Hoarseness of voice,)
  • Hypertension
  • Peripheral Vascular Complications
  • Hypotension(Low blood pressure).
  • Shortness of breath.

The clinical pictures of CT scan and Thoracic Endo Vascular Anuerysm Repair(TEVAR) seen above is that a patient 78 year old Male ,admitted with Hypotension, Unconscious state following sudden severe Chest pain radiating to back with left Haemothorax (blood in chest cavity) due to Type B Aortic Dissection and Rupture. Patient was resuscitated and Emergency Stent Graft was placed in leaking Thoracic Aorta above Coeliac Artery origin with Intercostal Drain.

Patient recovered his consciousness next day and revived back to normal routine due to timely intervention.