Thank you for your interest in the Duke Thoracic Aortic Surgery Program. Numerous diseases of the thoracic aorta are amenable to surgical treatment including aneurysms, pseudoaneurysms, aortic dissections, penetrating atherosclerotic ulcers, intramural hematomas, as well as congenital abnormalities such as coarctation of the aorta, among others. We offer expertise in the surgical treatment of all of these conditions in a high volume center with surgeons sub-specializing in the treatment of thoracic aortic disease.

Aneurysms of the Aortic Root
For patients with aneurysms of the aortic root, including those with the Marfan syndrome, we offer state-of-the-art valve-sparing root replacement techniques which preserve the native aortic valve while at the same time removing all of the diseased aorta (Figure #1). These valve-sparing procedures allow patients to potentially avoid the problems associated with prosthetic valves such as endocarditis and the need for anti-coagulation. For patients who are not candidates for valve-sparing root replacement, we offer biologic as well as mechanical root replacement options depending on patient preference.

 

Aneurysms of the Ascending Aorta
Surgical treatment of aneurysms of the ascending aorta (Figure #2) and aortic arch frequently require the use of specialized perfusion techniques including deep hypothermic circulatory arrest (DHCA) to ensure protection of the central nervous system while at the same time allowing complete repair of the anatomical defect. To ensure maximal safety with the use of these techniques, our Thoracic Aortic Surgery Team includes Certified Cardiac Perfusionists with long-term experience in these complex perfusion strategies as well as Cardiac Anesthesiologists with a sub-specialty interest in aortic surgery and the expertise required to care for these complicated patients. Further, patients undergoing these procedures have online monitoring of their central nervous system with electroencephalography (EEG) by our Neurophysiologic Monitoring Service (see below) during their operation to guide brain protection and ensure maximal patient safety.

 

Aneurysms of the Descending Aorta
The majority of aneurysms of the descending thoracic aorta can now be repaired using endovascular techniques (Figure #3) and Duke offers expertise in this emerging area of cardiovascular medicine. In addition, we are currently participating in several major thoracic endovascular stent graft clinical trials investigating the use of these techniques in high-risk patients with other conditions of the descending thoracic aorta requiring surgical therapy such as Type B aortic dissection. All of these procedures are performed by a team consisting of both Cardiothoracic and Vascular surgeons as well as Cardiac Anesthesiologists with experience in this area. This minimally invasive procedure has decreased the mortality as well as the major complication rate associated with open repair and allows the majority of patients to be discharged within 1-2 days with return to full activity in several weeks.

 

Aneurysms of the Thoracoabdominal Aorta
Aneurysms of the thoracoabdominal aorta represent a formidable surgical challenge and their treatment is generally limited to large referral centers such as Duke with expertise in the complex techniques necessary for successful repair. As with descending thoracic aneurysms, the surgical repair of these lesions carries a risk of spinal cord ischemia and online monitoring of the spinal cord during surgery with somatosensory evoked potentials (SSEPs) and motor evoked potentials (MEPs) are utilized to minimize this risk (see below). In addition, we utilize other adjuncts to further protect the spinal cord including the use of neuroprotective pharmacologic agents, cerebrospinal fluid drainage, distal aortic perfusion, mild hypothermia, and intercostal artery re-implantation to maximize positive neurologic outcomes.

 

Acute Aortic Dissection
Acute aortic dissection represents the most common aortic condition requiring urgent surgical therapy. This condition is generally classified as either Type A, which refers to dissection involving the ascending thoracic aorta (Figure #5), or Type B, which involves the descending aorta. Type A dissection represents a surgical emergency with a mortality rate as high as 1% per hour without surgical treatment. Duke Life Flight (Figure #4) allows emergency air transport of these critically ill patients to Duke where they are taken directly to the operating room for surgical intervention with Duke cardiac surgeons. The vast majority of these cases may be managed with aortic root repair and re-suspension of the native aortic valve without the need for aortic root replacement (Figure #6).

 

Type B dissection patients also frequently require surgical intervention for so called "complicated" dissection. This generally refers to Type B dissection associated with impending or frank rupture or malperfusion of critical vascular beds. These patients may also gain immediate access to the Duke system via Life Flight where these complicated lesions are increasingly being treated with endovascular stent techniques (Figure #7) with results superior to open surgery.

 

Minimizing the Risks – the Duke Surgery Advantage
Historically, the biggest concern after perioperative mortality regarding the surgical treatment of Thoracic Aortic disease has been the risk of neurologic injury. For operations on the ascending aorta and aortic arch requiring the use of DHCA for repair, concern centers on injury to the brain, whereas for surgery on the descending and thoracoabdominal aorta injury to the spinal cord is the primary issue. As such, all patients undergoing these procedures at

Fig. 7

Duke are monitored by our Neurophysiologic Monitoring Service which includes Neurologists specializing in monitoring of the central nervous system who are present in the operating room during surgery to immediately detect potential problems as they arise. This immediate detection offers the best potential for correction and avoidance of adverse neurologic outcomes. For operations on the ascending aorta and aortic arch, as well as descending aortic operations requiring the use of DHCA, we use intraoperative EEG to guide our perfusion strategy and provide maximal brain protection. Duke is the only center in the Southeast employing online central nervous system monitoring with EEG to guide cooling and perfusion strategies for the use of DHCA in repair of Thoracic Aortic disease.

 

For descending thoracic and thoracoabdominal aortic operations, somatosensory (SSEPs) and motor evoked potentials (MEPs) are used to allow the immediate detection of problems related to the spinal cord. Studies have demonstrated that these problems may frequently be reversed if detected and treated immediately and the use of SSEPs and MEPs allow us to do just this. As with EEG, Duke is the only center in the Southeast employing online spinal cord monitoring with both SSEPs and MEPs during all open and endovascular thoracic and thoracoabdominal aortic procedures.

 

A Multidisciplinary Team of Experts
Treatment of Thoracic Aortic disease requires a team of dedicated individuals including sub-specialty trained surgeons, anesthesiologists, neurophysiologists, perfusionists, OR nurses and staff, as well as critical care nurses and physicians to ensure patients with these life-threatening disorders receive state-of-the-art care to maximize the potential for optimal outcomes with complex aortic surgery. The Duke Thoracic Aortic Surgery Program provides patients with such expertise in the number one rated medical center in the South.

G. Chad Hughes, MD, Assistant Professor and Director, Thoracic Aortic Surgery Program, Cardiovasular & Thoracic Surgery
Madhav Swaminathan, MD, Assistant Clinical Professor, Cardiac Anethesia
Aatif Husain, MD, Associate Professor, Neurology
Gregory Smigla, CCP, Perfusionist
Nicole Martin, RN