Aortic dissection is a catastrophic, though, relatively uncommon illness. Forty percent of acute cases are classified as Type B (descending) aortic dissections. Hypotension and shock on presentation is seen in about 3% of cases. Aortic rupture, a frequent cause of hypotension in aortic dissection, causes massive hemorrhage and associated high mortality rate (> 50%). Due to the location and anatomic relations of the descending aorta, aortic rupture at this level usually causes a left hemothorax. In this report, we present a case of ruptured Type B aortic dissection causing a right hemothorax and draw attention to this relatively uncommon clinical clue to rupture.
A 55 y/o black male with a history of hypertension presented with nausea and progressively worsening abdominal pain with radiation to the back for 36 hours. His blood pressure on presentation was 224/120 mm Hg. CT scan revealed Type B dissection extending to the common iliac arteries, but not affecting the visceral perfusion. Patient was placed in the medical ICU and blood pressure was controlled with intravenous beta-blockers and nitropresside then oral medications. Six days later, the patient began complaining of abdominal and back pain associated with shortness of breath. A chest x-ray at that time showed a new large right pleural effusion. A CT of chest, abdomen and pelvis was performed and confirmed the right pleural effusion with extravasation of contrast into right chest with no further extension of dissection compared to previous CT scan. Even though the patient had remained hemodynamically stable prior to surgery, he was emergently taken to the OR for repair of a contained ruptured thoracic aortic dissection. Intra-operative transesophageal echocardiogram revealed a pseudoaneurysm of the mid-thoracic aorta with a periaortic hematoma. A right chest tube was placed in the OR and 1000 cc of blood was drained. A lumber drain was placed after induction of anesthesia. For repair of aorta the patient was placed on axillary femoral bypass. Though a left thoracoabdominal incision, aorta was replaced with a graft starting at the left subclavian to the celiac artery with reimplantation of intercostals T8-L2. At surgery a free rupture of the mid thoracic aorta at the level of inferior pulmonary vein contained by the posterior mediastinal tissue was seen with extension across the midline into right pleural cavity. Postoperatively the patient suffered paraplegia, renal failure and pneumonia and died on the 25th postoperative day from sepsis.
Rupture of the descending thoracic aorta results in bleeding into the left pleural cavity. A right hemothorax secondary to rupture of aortic dissection is rare. To our knowledge only four cases - excluding cases of ruptured non-dissecting aortic aneurysms- have been reported in the English literature. The right hemothorax has been described in most of the cases to develop from a medial tear in the aorta at the level of the mid thoracic spine that bleeds into the posterior mediastinum and crosses the mid line to rupture into the right pleural space. Establishing a prompt and accurate diagnosis in these cases is important to prevent early death through surgical intervention. 50% of the previously reported cases died intraoperatively due to delay in diagnosis.
Type B aortic dissection with rupture into the right hemithorax is a rare but potentially fatal disorder that should be diagnosed rapidly. This uncommon presentation should always be considered in patients with chest pain and right pleural effusion. This report emphasizes the fact that despite the anatomic location of descending aorta close to the left pleural cavity, aortic rupture can lead to right sided hemothorax.
M.S. Abu-Fadel, None.