Department of Surgery News


New FDA-Approved Stent Device Allows for Minimally Invasive Treatment of Complex, Life-Threatening Aneurysms

Drs. Shang A. Loh (left) and Apostolos K. Tassiopoulos

STONY BROOK, NY, May 15, 2013 — Two members of the Vascular Surgery Division have become the first physicians on Long Island to successfully implant fenestrated endografts in patients with complex abdominal aortic aneurysms (AAAs). The first procedures took place in February, and more have followed.

Both vascular surgeons who performed these procedures, Apostolos K. Tassiopoulos, MD, professor of surgery and chief of vascular surgery, and Shang A. Loh, MD, assistant professor of surgery, have the advanced technical skills required for doing fenestrated endovascular aortic aneurysm repair (FEVAR).

Fenestrated aortic endografts are custom made to suit each individual patient’s anatomy, based on reconstructions of the patient's vascular anatomy derived from computed tomography (CT) scans.

These tube-like stent devices have precisely placed openings in them — full-circular holes and/or semi-circular scallops, called fenestrations — that allow extension of the "seal zone" above the kidney arteries, thus permitting normal blood flow to the kidneys and bowel.

FEVAR represents the latest advance in the treatment of abdominal aortic aneurysm, and offers more patients the benefits of minimally invasive surgery for this life-threatening condition.

Fenestrated endografts make possible the minimally invasive endovascular repair of AAAs that are located very close to the arteries supplying the kidneys and, hence, are not suitable for the standard aortic endografts. The purpose of aortic endografts, in general, is to seal off the AAAs in order to prevent blood from flowing into them.

Fenestrated endografts recently received approval from the Food and Drug Administration (FDA) and require particular technical expertise for insertion. Only select centers in the nation with appropriately trained vascular surgeons are offering this new treatment option.

Dubbed the "silent killer," AAA is fatal in most cases if the aneurysm ruptures before being repaired. Therefore, early detection and repair are crucial.

"Abdominal aortic aneurysms seldom give warning signs. The condition occurs when a weak spot on the wall of the abdominal aorta balloons out — something like a bulge on an overinflated tire," explains Dr. Tassiopoulos.

An estimated one million Americans live with an undiagnosed AAA — including 20,000 in Suffolk County alone. According to the Centers for Disease Control and Prevention, AAA is more common in men and in individuals aged 65 years and older.


Fenestrated Endovascular Aortic Aneurysm Repair
Fenestrated endograft placed within abdominal aortic aneurysm, showing arteries that feed kidneys through custom-tailored openings (fenestrations) in top of graft. (Click on photo to enlarge).

Minimally invasive endovascular aortic aneurysm repair (EVAR) has revolutionized treatment of AAAs in recent years. The technique involves insertion of a self-expanding, fabric-covered stent inside the aneurysm, using two small groin incisions for access to arteries, to effectively exclude the aneurysm in the aorta from circulating blood.

The EVAR technique has significantly reduced the mortality and complication rate associated with traditional open repair of AAAs, and has become the preferred treatment method for most patients, including a significant number of patients who would have been turned down for a traditional open repair because of other health issues.

Unfortunately, not all patients with AAA are candidates for EVAR. One of the most common limitations with standard endografts is an inadequate seal zone — also called a short neck — indicating little or no distance between the top of the aneurysm and the take-off of the arteries feeding the kidneys (renal arteries).

When a short neck is present, the standard stent graft is unable to create a tight seal with the aortic wall, thus allowing continuous blood flow into the aneurysm.

An estimated 10% of all patients with AAA have the short neck condition, and thus are not candidates for standard EVAR repair. Until recently, their choices for treatment were limited, and most had to undergo a traditional open AAA repair.

Custom-made fenestrated endografts, which are designed based on each individual patient’s vascular anatomy using CT scans, incorporate tailored openings in the top section of the graft that allow extension of the seal zone above the kidney arteries without compromising blood flow to the kidneys and intestine.

During the FEVAR procedure, stents are put through the graft fenestrations into the renal arteries to ensure that placement of the aortic endograft is accurate and secure, blood flow to the kidneys is preserved, and the aneurysm is successfully sealed off.

FEVAR represents the latest advance in AAA treatment. The custom-made endograft is the most state-of-the-art device today for AAA treatment. This new device enables experienced vascular surgeons to treat patients with very complex aortic anatomy in a minimally invasive way.

Drs. Tassiopoulos and Loh are members of Stony Brook Medicine’s multidisciplinary team of aortic disease experts that provides the most advanced treatments of aortic conditions on Long Island.