تسلخ الأبهر

Definition

Aortic dissection is a tear in the inner layer of the aorta that lets blood enter between the wall layers, creating a false lumen that can block aortic branches or rupture outward.

Types

• Type A: involves the ascending aorta and needs urgent surgery
• Type B: descending aorta only, usually managed medically or with a stent graft

Risk factors

Hypertension (most important), Marfan syndrome, bicuspid aortic valve and cocaine.

Symptoms

• Sudden severe tearing pain in the chest or between the shoulder blades
• A BP or pulse difference between the arms
• Branch occlusion: stroke, abdominal pain, limb weakness, low urine output
• May cause acute aortic regurgitation or tamponade

Diagnosis

CT angiography or transoesophageal echocardiography.

Treatment

• Lower heart rate first with an IV beta-blocker, then BP, to reduce force on the wall
• Strong analgesia
• Urgent surgery for type A

Nursing care

• Measure BP in both arms and watch limb pulses, consciousness and urine output
• No anticoagulants or thrombolytics

Exam point

Confusing dissection with MI is dangerous, because thrombolysis can be fatal in dissection.