The aorta is the largest artery in the human body, carrying oxygen-rich blood directly from the heart’s left ventricle to the rest of the circulatory system. When a section of this vessel becomes diseased or damaged, the risk of catastrophic rupture makes surgical intervention necessary. Fortunately, modern cardiovascular surgery has advanced significantly, and the diseased or damaged segments of the aorta can be successfully replaced with artificial materials.
Conditions Necessitating Aortic Replacement
Aortic replacement surgery is necessary when the vessel wall weakens, risking life-threatening failure, primarily due to an aortic aneurysm or an aortic dissection. An aneurysm is a localized ballooning of the vessel wall caused by chronic weakening. The risk of rupture increases significantly as the aneurysm grows larger than 5.0 to 5.5 centimeters, depending on location and patient factors.
Aortic dissection is an acute medical emergency where a tear occurs in the innermost layer of the wall. Blood rushes through this tear, separating the layers and creating a false channel that compromises the aorta’s structural integrity. This condition can rapidly lead to organ damage or rupture and often requires immediate surgery.
Certain inherited conditions compromise the structural proteins within the aortic wall, predisposing individuals to failure at a younger age. Genetic disorders such as Marfan Syndrome and Ehlers-Danlos Syndrome weaken the connective tissue, making the aorta prone to dilation and dissection. These patients often require preemptive replacement of the aortic root and ascending aorta to prevent a lethal aortic event.
Surgical Strategies and Graft Materials
Replacing the aorta involves removing the damaged section and bridging the gap with a synthetic conduit, which acts as a permanent substitute for the natural vessel. The primary material used for these grafts is Dacron, a durable polyester that is highly compatible with the human body. These grafts are designed to outlast the patient’s lifetime without rejection or calcification.
The surgical approach depends on the segment requiring repair. Disease in the ascending aorta or aortic root often requires open-heart surgery, involving a median sternotomy (incision through the breastbone). If the aortic valve is also damaged, a composite graft procedure replaces the aortic root and valve simultaneously, though a valve-sparing technique may be used to preserve the native valve.
For disease affecting the descending or abdominal aorta, surgeons may use Endovascular Aortic Repair (EVAR) or Thoracic Endovascular Aortic Repair (TEVAR). This less invasive technique involves delivering a stent-graft through small incisions in the groin arteries using catheters. The stent-graft reinforces the aortic wall and excludes the aneurysm from blood flow, offering a faster recovery than traditional open surgery. Open surgical repair remains the standard for complex aortic arch repairs or when the anatomy is unsuitable for endovascular methods.
Post-Surgical Management and Long-Term Outlook
The immediate post-surgical recovery depends on the procedure performed. Patients undergoing open-heart surgery for the ascending aorta typically spend one to two nights in the Intensive Care Unit (ICU). The total hospital stay for open repair usually ranges from four to seven days, followed by a recovery period at home.
Patients must adhere to strict sternal precautions for about six weeks following open surgery, avoiding lifting anything heavier than five to ten pounds to allow the breastbone to heal. Endovascular repair often results in a shorter hospital stay and fewer immediate activity restrictions due to its minimally invasive nature. Early and moderate walking is encouraged for all patients to aid circulation.
Long-term success relies on diligent management and lifestyle adjustments to protect the remaining aorta and the graft. Lifelong strict control of blood pressure is necessary, as hypertension increases the risk of future aneurysms or graft issues. Physicians often prescribe medication to maintain blood pressure at a lower target range than is typical.
Smoking cessation is the most impactful lifestyle change a patient can make to slow aortic disease progression. Patients should adopt a heart-healthy diet, maintain a healthy weight, and engage in regular, moderate exercise, avoiding heavy isometric weightlifting that could spike blood pressure. Regular follow-up imaging, typically with CT or MRI, is required to monitor the graft and remaining aorta. For endovascular repairs, imaging is often performed annually, while open repair surveillance may become less frequent if the initial post-operative imaging is stable.