Trends in Use Reported for the Cook Zenith Fenestrated EVAR Device in the United States
April 20, 2017—In the Journal of Vascular Surgery, Jessica P. Simons, MD, et al reported on the trends in use of the Zenith fenestrated endovascular graft (Cook Medical) for abdominal aortic aneurysms (AAAs), which received US Food and Drug Administration approval in 2012 and is the only available fenestrated device for endovascular aneurysm repair (EVAR) in the United States (2017;65:1260–1269).
As background, fenestrated endografts are customized, patient-specific, endovascular devices with potential to significantly reduce morbidity and mortality of short-neck infrarenal and juxtarenal AAA repair. This technology is among the most technically complex catheter-based procedures and, therefore, inherently associated with serious risk for device-related complications. The objective of the study was to define patterns of physician and hospital adoption of the Zenith fenestrated device.
Deidentified data sets that contained numbers of physicians trained, orders by physicians and hospitals, and designs were provided for Zenith fenestrated devices ordered in the United States from April 2012 to August 2015. The investigators evaluated the number of physicians trained, the number of devices ordered, hospital characteristics, and fenestration/scallop design configurations. Although Cook Medical assembled the data sets, the investigators noted that it played no role in study design, analysis, or interpretation of data.
As summarized in the Journal of Vascular Surgery, from August 2012 to August 2015, 553 physicians attended formal Zenith fenestrated training sessions, and 388 (70%) ordered a total of 2,669 devices. An increase in orders per month (nine in June 2012 and 91 in August 2015, 911% growth; P < .001) and in number of physicians ordering per month (eight in June 2012 and 62 in August 2015, 675% growth; P < .001) was observed.
Teaching hospitals accounted for 1,703 (64%) orders of the Zenith fenestrated device (Midwest, 927 [35%]; South, 799 [30%]; Northeast, 547 [20%]; West, 396 [15%]). Of 553 trained physicians, 165 (30%) ordered no devices, 116 (21%) ordered one device, 144 (26%) ordered two to five devices, 61 (11%) ordered six to 10 devices, 39 (7%) ordered 11 to 20, and 28 (5%) ordered more than 20 devices. Physicians contributing more than 6 months of data (n = 336) ordered an average of three devices per year (standard deviation, 4); 272 (81%) ordered ≤ 5 devices per year, 15 (4.5%) ordered 11 to 20 devices per year, and three (0.9%) ordered > 20 devices per year.
Design details were available for 98% (2618 of 2669) of devices. The most common designs were two small fenestrations/one scallop (1443; 55%), two small fenestrations/one large fenestration (568; 22%), one small fenestration/one scallop (173, 6.6%), and two small fenestrations (169; 6.5%).
The average number of target vessels incorporated in each design was 2.7 per device; 2,071 (79%) incorporated three, and 398 (15%) incorporated two, reported the investigators in the Journal of Vascular Surgery.
Since 2012, monthly orders of the Zenith fenestrated device have increased ninefold, with 553 physicians trained. Unlike the experience of rapid dissemination seen with infrarenal endografts, only 28 (5%) physicians have ordered > 20 devices, whereas 165 (30%) have ordered none, and 272 (81%) ordered ≥ 5 devices per year. Assuming that volume generally correlates with outcomes, this adoption pattern raises questions whether fenestrated technology should be regionalized to high-volume centers, advised the investigators in the Journal of Vascular Surgery.