Fenestrated endovascular aneurysm repair is financially viable at a high-volume medical center with positive hospital contribution margins and physician payment.

OBJECTIVE: To examine hospital finances and physician payment associated with fenestrated endovascular aneurysm repair (FEVAR) for complex aortic disease at a high-volume center and to compare the costs and reimbursements for FEVAR with open repair, and their trends over time. METHODS: Clinical and financial data were collected retrospectively from electronic medical and administrative records. Data for each patient included inpatient and outpatient encounters 3 months before and 12 months after the primary aneurysm operation. RESULTS: Between 2007 and 2017, 157 and 71 patients were treated with physician-modified endograft (PMEG) and Cook Zenith Fenestrated (ZFEN) repair, respectively. Twenty-one patients who were evaluated for FEVAR underwent open repair instead. The 228 FEVAR patients provided a total positive contribution margin (reimbursements minus direct costs) of $2.65 million. The index encounter (the primary aneurysm operation and hospitalization) accounted for the majority (90.6%) of the total contribution margin. The largest component (50.3%) of direct cost for FEVAR from the index encounter was implant/graft expenses. The average direct costs for FEVAR and for open repair from the index encounter were $34,688 and $35,020, respectively. The average contribution margins for FEVAR and for open repair were approximately $10,548 and $21,349, respectively, attributable to differences in reimbursement. The average direct cost for FEVAR trended down over time as cumulative experience increased. Average reimbursement for FEVAR increased after Centers for Medicare and Medicaid Services approved payments with the Investigational Device Exemption (IDE) trial for PMEG in 2011, and a new technology add-on payment for ZFEN in 2012. These factors transitioned the average contribution margin from negative to positive in 2012. The average physician payments for PMEG increased from $128 to $5848 after the start of the IDE trial. The average physician payments for ZFEN and for open repair between 2011 and 2017 were $7597 and $7781, respectively. CONCLUSIONS: FEVAR can be performed at a high-volume medical center with positive contribution margins and with comparable physician payments to open repair. At this institution, hospital reimbursement and physician payments improved for PMEG with participation in an IDE trial, while hospital direct costs decreased for both PMEG and ZFEN with accumulated experience.

Long-term durability of a physician-modified endovascular graft.

We present a unique assessment confirming the long-term durability of a physician-modified endograft deployed as part of an Investigational Device Exemption clinical trial (NCT# 01538056). After receiving an intact postmortem aorta 7 years after the index procedure, we performed microcomputed tomography, necropsy, and metallurgical analysis on the specimen. Microcomputed tomography showed a single strut fracture not noted during previous surveillance. Necropsy revealed no graft fabric compromise, and examination of all three visceral fenestrations showed excellent alignment with no evidence of degradation. Analysis of the strut fracture implicated an initially small, fatigue-induced crack that likely succumbed during postmortem handling.

A reliable method for renal volume measurement and its application in fenestrated endovascular aneurysm repair.

OBJECTIVE: Renal volume has been shown to correlate with renal function. Renal volume and renal function both decline steadily in the sixth decade of life and beyond. We sought to assess (1) the inter-rater reliability for manually measuring renal volume using computed tomography and (2) change in renal volume over time as it relates to renal function in fenestrated endovascular aortic aneurysm repair (FEVAR). METHODS: This study was conducted as part of a physician-sponsored investigational new device (#NCT01538056). First, 30 consecutive kidneys of preoperative FEVAR patients were independently measured by two raters using manual segmentation and three-dimensional modeling software. Renal volumes were calculated and compared. Intraclass correlation was calculated between the two observers. Second, renal volumes were then recorded for 85 patients undergoing FEVAR with follow-up out to 5 years. Demographic data, comorbidities, creatinine, glomerular filtration rate (GFR), renal artery stenosis or occlusion, and bilateral renal volume measurements were analyzed. Multivariate analysis was performed to delineate association of these variables with total renal volume (TRV). RESULTS: The intraclass correlation coefficient for our renal volume measurements was 0.97 (95% confidence interval, 0.81-0.99), indicating excellent correlation. Renal volume was strongly correlated with GFR. Our multivariate analysis model predicts a 17.9 mL/min increase in GFR with each 20% increase in TRV. After adjustment for all other known correlates of renal function, renal volume remained as the only significant predictor of renal function. CONCLUSIONS: Renal volume can be measured with high reliability using manual segmentation and computed tomography scans. In our baseline analysis, TRV was strongly correlated with renal function. These findings support the potential for renal volume as a surrogate for renal function.

Aortic neck dilation is not associated with adverse outcomes after fenestrated endovascular aneurysm repair.

OBJECTIVE: Long-term outcomes after endovascular aneurysm repair (EVAR) are threatened by aortic neck dilation (AND), graft migration, and subsequent endoleak development. The aim of this study was to determine the rate of AND and the occurrence of endoleaks after fenestrated EVAR of juxtarenal aneurysms with physician-modified endovascular grafts (PMEGs). METHODS: The study included 77 patients presenting with asymptomatic and ruptured juxtarenal abdominal aortic aneurysms treated with PMEGs who received radiologic follow-up. Analysis of computed tomography images took place on a three-dimensional workstation (TeraRecon, San Mateo, Calif). Aortic neck diameter was measured before and after EVAR at the lowest patent renal artery outer wall to outer wall. Significant AND was defined as >3-mm increase between baseline and follow-up, and sac regression >5 mm was considered significant. The patient's 1-month initial postoperative computed tomography measurement was considered baseline. The rate of AND was measured by comparing the baseline measurement with measurements at 6 months, 12 months, and annually thereafter up to 4 years. RESULTS: In this cohort of patients, 75% were men with a mean age of 74 ± 7.9 years. Median preoperative aneurysm size was 62 (57-73) mm, and median follow-up was 12 (3.5-30) months. Mean endograft oversizing was 17% ± 12.5%, and mean seal zone length was 41 ± 11 mm. At 1-year follow-up, the median aortic neck increase was 1.7 (0-3) mm. Maximum aneurysm size decreased dramatically during the first postoperative year, with significant sac regression in 65% of the patients. Aortic neck diameter at 1 year did correlate positively with the percentage of device oversizing. No other correlations were found. During the 4-year follow-up, there were no cases of type IA endoleaks. CONCLUSIONS: AND does not influence outcome after endovascular repair of juxtarenal aneurysms using PMEGs. These midterm results support the applicability of PMEGs in juxtarenal aneurysm repair.

Procedural and perioperative results in patients treated with fenestrated endovascular aneurysm repair planned by automated software in a physician-sponsored investigational device exemption trial of physician-modified endografts.

OBJECTIVE: Fenestrated endovascular aneurysm repair (FEVAR) has been used successfully to treat patients with juxtarenal abdominal aortic aneurysms (JAAAs). Barriers to wide adoption of FEVAR include complexity in planning of fenestration locations on endografts. The purpose of this study was to validate the use of automated planning software to design fenestrated endografts and to treat patients with complex abdominal aortic aneurysms. METHODS: Patients with JAAA who were not candidates for open repair were enrolled into the automated planning arm of an ongoing investigational device exemption clinical trial and treated with FEVAR. Patient-specific fenestration size and location were determined by automated planning software using patient imaging data and algorithms that account for the interaction between the endograft delivery system and angulated aortic anatomy. Standard, off-the-shelf abdominal aortic aneurysm endografts from multiple manufacturers were modified on the back table by the physician according to the automated graft plan in the form of a patient-specific three-dimensional printed cylindrical template. Endografts typically included fenestrations for the superior mesenteric artery and both renal arteries. Procedural, perioperative, and long-term clinical and imaging data were collected per protocol. RESULTS: Thirty nonoperative JAAA candidate patients (American Society of Anesthesiologists class ≥3) were consented and treated with fenestrated endografts planned by automated software. The mean age was 74 ± 7 (61-86) years. The mean aneurysm diameter was 61.3 mm (range, 49-96 mm), and the mean infrarenal neck length was 6.1 mm (range, 2-15 mm). At the index procedure, 100% (30/30) of the patient-specific, surgeon-modified grafts were implanted with preservation of 97% (84/87) of branch vessels and a mean final proximal seal zone length of 41.9 mm (range, 27.3-60.6 mm). Three renal arteries were not cannulated during the index procedure because of complications not related to graft planning. The 30-day mortality rate in these high-risk JAAA patients was 6.7% (2/30), and both deaths were unrelated to the aneurysm. The 30-day major adverse event rate was 16.7% (5/30). There were no type IA or type III endoleaks, ruptures, or conversions to open surgery through 30 days. CONCLUSIONS: This automated FEVAR planning software accurately and efficiently identifies fenestration locations for vital branch arteries, thus simplifying the planning process and facilitating the FEVAR procedure. Validated automated FEVAR planning could help bring this beneficial therapy to most patients harboring JAAAs.

Midterm results from a physician-sponsored investigational device exemption clinical trial evaluating physician-modified endovascular grafts for the treatment of juxtarenal aortic aneurysms.

OBJECTIVE: The objective of this study was to report midterm results of an ongoing physician-sponsored investigational device exemption pivotal clinical trial using physician-modified endovascular grafts (PMEGs) for treatment of patients with juxtarenal aortic aneurysms who are deemed unfit for open repair. METHODS: Data from a nonrandomized, prospective, consecutively enrolling investigational device exemption clinical trial were used. Data collection began on April 1, 2011, and data lock occurred on May 31, 2015, with outcomes analysis through December 31, 2015. Primary safety and efficacy end points were used to measure treatment success. The primary safety end point was defined as the proportion of subjects who experienced a major adverse event within 30 days of the procedure. The primary efficacy end point was the proportion of subjects who achieved treatment success. Treatment success required the following at 12 months: technical success, defined as successful delivery and deployment of a PMEG with preservation of those branch vessels intended to be preserved; and freedom from type I and III endoleak, stent graft migration >10 mm, aortic aneurysm sack enlargement >5 mm, and aortic aneurysm rupture or open conversion. RESULTS: During the 50-month study period, 64 patients were enrolled; 60 began the implant procedure and 59 received the PMEG implant. Aneurysm anatomy, operative details, and lengths of stay were recorded and included aneurysm diameter (mean, 65.9 mm; range, 49-104 mm), proximal seal zone length (mean, 40.8 mm; range, 18.9-72.2 mm), graft manufacture time (mean, 55.1 minutes), procedure time (mean, 156.8 minutes), fluoroscopy time (mean, 39.6 minutes), contrast material use (mean, 75.3 mL), estimated blood loss (mean, 213 mL), and length of hospital stay (mean, 4.1 days) with intensive care unit length of stay (mean, 2.2 days). There were 145 fenestrations made for 110 renal arteries and 38 superior mesenteric arteries (SMAs). One patient had an SMA stent placed before the procedure for severe stenosis, and one subject had the SMA stented during the procedure. Renal arteries were stented whenever possible (93%). There were 102 stented renal arteries in 58 patients. There were no open conversions or explantations. Thirty-day mortality was 5.1% (3/59). There were zero type Ia, one type Ib, and two type III endoleaks during follow-up treated with successful reintervention. The overall rate of major adverse events at 30 days was 11.9%. The primary efficacy end points were achieved in 94.1% of patients. CONCLUSIONS: These midterm results are favorable and verify our early report that endovascular repair with PMEG is safe and effective for managing patients with juxtarenal aortic aneurysms. PMEG has exceptional midterm rates of morbidity, mortality, and endoleak and may outperform standard endovascular aneurysm repair with favorable anatomy. In patients who are poor open surgical candidates who present with symptomatic or ruptured juxtarenal aortic aneurysms, PMEG continues to be an extremely appealing option as reliable off-the-shelf solutions are not widely available. Preoperative planning remains the key ingredient for success with use of these techniques.

Evaluation of the learning curve for fenestrated endovascular aneurysm repair.

OBJECTIVE: The objective of this study was to evaluate the learning curve for fenestrated endovascular aortic aneurysm repair (FEVAR). METHODS: Data were collected prospectively on all FEVAR procedures conducted by a single surgeon between June 2007 and January 2015. During the study period, 136 FEVARs were performed, and this experience was divided into four quartiles each consisting of 34 cases. Clinical outcomes evaluated included perioperative death and major complications. Process outcomes included length of procedure, fluoroscopy time, contrast material use, estimated blood loss, and intensive care unit length of stay. RESULTS: During the study period, there was a statistically significant increase in the complexity of cases as evidenced by an increase in the proportion of cases with two or more fenestrations from 52.9% in the first quartile to 88.2% in the fourth quartile (P = .001). Despite this, there was a steady decrease in the proportion of patients suffering perioperative death or major complications from 23.5% in the first quartile to 8.8% in the fourth quartile. After adjustment for potential confounding factors, the odds of death or major complication were cut by 52.4% per quartile increase (95% confidence interval [CI], 7.8%-75.5%; P = .028). In addition, among cases with two or more fenestrations, geometric mean length of procedure was reduced from 223.8 minutes in the first quartile to 149.6 minutes in the fourth quartile, and geometric mean fluoroscopy time was reduced from 58.6 minutes in the first quartile to 31.5 minutes in the fourth quartile. After adjustment, there was an estimated 9.9% reduction in geometric mean procedure length per quartile increase (95% CI, 3.5%-15.9%; P = .003) and a 17.6% reduction in geometric mean fluoroscopy time per quartile increase (95% CI, 10.9%-23.8%; P < .0001). CONCLUSIONS: Despite an increase in case complexity, there was evidence for significant improvement in important clinical and process outcomes during the study period. We believe that much of this improvement was attributable to several key advances in the FEVAR procedure that were instituted during the study period and are discussed herein.

Endovascular treatment of thoracoabdominal aortic aneurysm using physician-modified endografts.

OBJECTIVE: To report an initial experience with physician-modified thoracic endografts for endovascular treatment of thoracoabdominal aortic aneurysm (TAAA). METHODS: Single-center cohort study of the treatment of TAAA using a physician-modified fenestrated thoracic endograft for patients deemed to be at high risk of open repair. The cohort includes 21 patients in a prospective physician-sponsored U.S. Food and Drug Administration-approved investigational device exemption study and three patients treated outside the investigational device exemption. The procedure involves physician modification of a Cook TX2 thoracic stent graft with reinforced fenestrations. Branch stents were iCast balloon expandable stents. Treatment success was defined as successful aneurysm exclusion with freedom from permanent organ system dysfunction and return to preoperative level of independent functional status. RESULTS: Twenty-four consecutive patients were treated. Twenty-one patients (88%) met the endpoint of treatment success at a mean of 11 months follow-up. One patient (4%) died within 30 days due to complications of spinal cord injury (SCI). One patient (4%) died 4 months postoperatively after a prolonged recovery from surgery. One other patient (4%) is alive 13 months after operation with permanent SCI. One renal reintervention has been required. No device failures have occurred. CONCLUSIONS: Early-term data suggest that physician-modified fenestrated thoracic endografts can be used to safely and effectively treat TAAA in patients at high risk of open repair. Physician-modified devices perform similarly to commercially manufactured grafts in terms of treatment success, SCI, perioperative death, and clinical outcome at short-term follow-up. Physician modification is immediately available and allows for a high level of customizability. Procedure success is contingent upon careful preoperative planning, patient selection, experienced providers, and a high volume center.

Early report from an investigator-initiated investigational device exemption clinical trial on physician-modified endovascular grafts.

OBJECTIVE: To determine whether a physician-modified endovascular graft (PMEG) is a safe and effective method for treating patients with juxtarenal aortic aneurysms who are deemed unsuitable for open repair. METHODS: A nonrandomized, prospective, consecutively enrolling investigational device exemption clinical trial was used. Data collected on patients treated with PMEG between April 2011 and August 2012 were analyzed. Subjects were followed with computed tomography, visceral duplex, and four-view X-ray at 30 days, 6 months, and 1 year. The protocol was designed to include follow-up to 5 years. The primary safety end point was the proportion of subjects who experienced a major adverse event (MAE) within 30 days of the procedure. The primary efficacy end point was the proportion of subjects experiencing treatment success. RESULTS: During the 16-month study period, 28 patients were consented and 26 underwent endovascular repair using PMEGs. Anatomic, operative details, and length of stay were recorded and included aneurysm diameter (mean, 62.5 mm), proximal neck length (mean, 4.4 mm), graft manufacture time (mean, 59.7 minutes), procedure time (mean, 169 minutes), fluoroscopy time (mean, 42.8 minutes), total contrast usage (mean, 63 mL), estimated blood loss (mean, 221 mL), and length of hospital stay (mean, 4.9 days). There were 63 fenestrations created for 48 renal arteries and 15 superior mesenteric arteries. Renal artery fenestrations were stented whenever possible (96%) and superior mesenteric artery fenestrations were all left unstented. There were no unanticipated adverse device events, no MAEs, and only a single minor adverse device event treated with a successful reintervention. At 30 days, there were no type I or III endoleaks and only four type II endoleaks (15.4%). Two patients died during the study period, one at day 23 from respiratory failure (in-hospital and 30-day mortality = 3.8%) and one at day 210 from urosepsis and congestive heart failure. MAEs occurred in 11.5% of patients at 30 days. The primary efficacy end point was achieved in 87.5% of patients (technical success 100%, freedom from migration, rupture or conversion, type I or III endoleaks, or sac enlargement = 100%, 100%, 87.5%, and 87.5%, respectively). CONCLUSIONS: These preliminary data suggest that endovascular repair with PMEG is safe and effective for managing patients with juxtarenal aortic aneurysms. Endovascular repair with PMEG has acceptable early rates of morbidity, mortality, and endoleak. This endovascular aortic strategy is particularly appealing for those patients presenting with symptomatic or ruptured aortic aneurysms until reliable off-the-shelf solutions become widely available.