Endovascular Aortic Repair Stent Grafts – a $1B market with CAGR of 5-6% through 2025

The AAA device market is over $1B in 2017. Currently 80% of all AAA elective repairs are being performed using an endovascular approach. This is due to the less-invasive nature, reduced peri-operative morbidity and mortality, decreased length of hospitalization, need for blood products, and intensive care unit stay.

Abdominal aortic aneurysms are more common in men and among population aged 65 years and above with the prevalence is six times greater in men. As per various screening studies on the older population, the prevalence of AAA was 1.3% in women compared with 7.6% in men.

As of January 2014, Medicare covers AAA screening for eligible beneficiaries without requiring a referral as part of the Initial Preventive Physical Examination, (also commonly known as the “Welcome to Medicare Preventive Visit”). This modification in reimbursement has identified an increased number of patients at risk.

Approximately 133,000EVAR stent grafts were used to treat AAA patients in 2015, and this number is expected to increase by 5-6% by 2025.When the EVAR stent graft initially entered the market, complication rates were higher than open surgery. Today, with innovations in devices and advancements surgical procedures, the complication rates are now minimal; however, some endovascular grafts have been shown in the postoperative period to be prone to leakage, called endoleaks, and studies have shown that this occurs in approximately 15% of standard EVARs.

In 2016, EVAR is associated with equal long-term results as well as lower perioperative morbidity and mortality rates compared to open surgical resection and has become the standard of care for treatment of AAA requiring intervention when clinically applicable. After almost three decades, EVAR stent grafts continue to evolve to improve health outcomes and increase the number of patients who are good candidates for the device, which is currently approximately 50% of AAA patients. As seen below, there are over 16 companies who manufacture stent grafts for the endovascular repair of AAA, with different target patient cohorts and that deliver advantages and some clinical challenges. It is essential that new technologies in this space are properly positioned against other devices with medical device consultancy.

Even after 30 years, this space in the medical device field demands innovation due to the morphological diversity between patients, as well as the need to increase device compatibility towards more AAAs. This means start-ups in this space should seek medical device consulting services to grasp the competitive landscape of the field and position their technology for the most rapid adoption and highest revenue capture. One of the more notable FDA-approved innovations in recent years are fenestrated stent grafts. In 2012, such grafts were approved for use above the renal arteries with openings in the stent to allow blood to flow to the kidneys. Another more recent and innovative device approval is endostapling and endoanchors. These devices are not stents, but rather supplementary support that reduces the need for reintervention by preventing stent graft migration and leaks.

Approximately 20 EVAR stent product lines are approved by the FDA, and their various attributes provide specific advantages in certain anatomical environments, providing surgeons numerous options in device selection. 

Astent graft includes an impermeable fabric supported by a metal skeletonthat is guided to the aorta through the femoral artery. The stent graftis placed inside the aortic wall and is sealed above and below the aneurysm to displace circulatory pressure away from the weak areas of the aortic wall. These grafts come in various configurations, to address anatomical differences and clinical challenges between patients. For example, some stents are self-expanding, while others require a balloon for expansion. The fixation mechanism also varies among stents; some stents require a compression fit, while others rely on hooks or barbs to stay in place. Many stents are bifurcated to support the iliac arteries as well. As noted in the list below, there are many companies offerstent graft variation and innovation in this market space. Investments in new technologies should be properly vetted and valuated through medical device consultancy.

• Aptus Endosystem 
• Bolton Medical
• C.R. Bard
• Cook Medical
• Cordis
• Endologix
• GRIKIN Advanced Materials
• Johnson & Johnson
• Jotec
• LifeTech Scientific
• Lombard Medical Technologies
• Medtronic
• St. George Medical
• Terumo (Vascutek)
• TriVascular Technologies
• W.L. Gore & Associates 

EVAR requires precise, high-resolution medical imaging in the management of AAA. Several modalities are available for clinicians assessing AAA patients and are discussed below:

• Spiral computed tomography angiography (spiral CTA) has been demonstrated to be the best imaging modality in patient pre- and post-operative assessments and surveillance. This technique is less invasive than conventional angiography, whose use has declined in AAA management.
• Magnetic resonance angiography (MRA) is another high-resolution modality. This technique is more sensitive in detecting endoleaks in patients after EVAR, and does not require the use of iodinated contrast material or radiation, unlike spiral CTA. However, this modality is more expensive and time consuming.
• Ultrasonography possesses a high sensitivity and specificity, while remining noninvasive and inexpensive. Intravascular ultrasounds are able to provide a 360° cross-sectional view of the vessel, yet operator dependency remains. This method is invasive, and typically only used for research purposes.This technique also does not subject the patient to ionizing radiation; however, research has shown that this method is less accurate in diameter measurements and it is more operator-dependent. 

Below are other devices and techniques not yet on the market, butare in the regulatory approval process or in clinical evaluation: 

• Chimney technique—similar to the fenestrated graft, the chimney technique preserves blood flow to the kidneys; however, the device requires less customization between patient, reducing costs.
• Sandwich technique—this method is already being used by surgeons off-label, and works similarly to the chimney technique. This method allows revascularization of up to four side branches of the aorta, versus two. The advantage to this technique is that it can be used in patients not deemed suitable for conventional endovascular aneurysm repair.
• Multilayer stent—uses multiple, braided layers of material to prevent aneurysm while still allowing blood flow to highly-branched areas of the aorta.
• Sac-anchoring endoprosthesis—consists of two stent grafts with polymer-filled endobags on the outside of the stent. The polymer filled endobags enlarge to a pressure preset to support the stents within the aneurysm sac.

While there are many companies in the AAA space, the market is still in need of novel devices that decrease reinterventions and improve patient outcomes. It is essential that early-stage technologies have formed competitive and commercialization strategies through medical device consulting services. Doing this will ensure a more direct path to market, or an accelerated exit strategy.