Initial clinical experience with a new low-profile thoracic endograft

A meta-analysis on the effect of proximal landing zone location on stroke and mortality in thoracic endovascular aortic repair

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) involving the aortic arch may increase the opportunity for stroke owing to disruption of cerebral circulation and embolization. In this study, a systematic meta-analysis was performed to examine the impact of proximal landing zone location on stroke and 30-day mortality after TEVAR.

METHODS

MEDLINE and Cochrane Library were searched for all original studies of TEVAR reporting outcomes of stroke or 30-day mortality for at least two adjacent proximal landing zones, based on the Ishimaru classification scheme. Forest plots were created using relative risks (RR) with 95% confidence intervals (CI). An I2 of <40% was regarded as minimal heterogeneity. A P value of <.05 was considered significant.

RESULTS

Of the 57 studies examined, a total of 22,244 patients (male 73.1%, aged 71.9 ± 11.5 years) were included in the meta-analysis, with 1693 undergoing TEVAR with proximal landing zone 0, 1931 with zone 1, 5839 with zone 2, and 3089 with zone 3 and beyond. The overall risk of clinically evident stroke was 2.7% for zones ≥3, 6.6% for zone 2, 7.7% for zone 1, and 14.2% for zone 0. More proximal landing zones were associated with higher risks of stroke compared with distal (zone 2 vs ≥3: RR, 2.14; 95% CI, 1.43-3.20; P = .0002; I2 = 56%; zone 1 vs 2: RR, 1.48; 95% CI, 1.20-1.82; P = .0002; I2 = 0%; zone 0 vs 1: RR, 1.85; 95% CI, 1.52-2.24; P < .00001; I2 = 0%). Mortality at 30 days was 2.9% for zones ≥3, 2.4% for zone 2, 3.7% for zone 1, and 9.3% for zone 0. Zone 0 was associated with higher mortality compared with zone 1 (RR, 2.30; 95% CI, 1.75-3.03; P < .00001; I2 = 0%). No significant differences were found in 30-day mortality between zones 1 and 2 (P = .13) and between zone 2 and zones ≥3 (P = .87).

CONCLUSIONS

The risk of stroke from TEVAR is lowest in zone 3 and beyond, increasing significantly as the landing zone is moved proximally. Furthermore, perioperative mortality is increased with zone 0 compared with zone 1. Therefore, risk of stent grafting in the proximal arch should be weighed against alternative surgical or nonoperative options. It is anticipated that the risk of stroke will improve with further development of stent graft technology and implantation technique.

A Single-Center Experience With Total Percutaneous Implantation of a Low-Profile Thoracic Aortic Stent-Graft

PURPOSE

To evaluate the safety and effectiveness of total percutaneous implantation of the Zenith Alpha Thoracic (ZTA) endograft in the treatment of diseases of the descending thoracic aorta.

MATERIALS AND METHODS

A retrospective cohort study of 56 consecutive patients undergoing total percutaneous ZTA implantation between 2018 and 2020 was performed in a single center. Patients' demographics, clinical characteristics, anatomical parameters, operative details, device features, and postoperative outcomes were assessed. The primary endpoint was ongoing clinical success. A Cox regression model was used to determine the predictive factors of worse postoperative outcomes.

RESULTS

Eighty-three ZTA endografts were implanted in 35 men and 21 women with a mean age of 69±11 years for the treatment of 26 degenerative aneurysms, 15 type B dissections, and 8 penetrating ulcers, among others. Primary technical success was 100%, with a 30-day ongoing clinical success rate of 94.6%. The 1-year ongoing clinical success rate was 91.1% (51 patients), and freedoms from all-cause mortality, type 1 and 3 endoleaks, and any unplanned reintervention were, respectively, 95.3%, 91.4%, and 88.2% at 1 year. During follow-up, there was one case of surgical conversion for an aorto-esophageal fistula. On the contrary, neither aneurysmal rupture nor significant aneurysmal expansion was recorded. Repair of ruptured thoracic aorta and a high ratio of sheath outer diameter to external iliac artery diameter were found to be independently associated with worse outcomes, with adjusted odds ratios of 4.4 [1.5-15.3] and 4.9 [1.1-23.9], respectively.

CONCLUSION

The outcomes of total percutaneous implantation of ZTA endograft show excellent primary technical success and favorable midterm ongoing clinical success. Factors associated with worse outcomes include the repair of ruptured aorta and a high sheath to access vessel ratio.

Single-center midterm results with the low-profile Zenith Alpha thoracic endovascular stent graft

OBJECTIVE

The analysis of endovascular treatment of thoracic aortic diseases using new low-profile stent grafts in large series is crucial to understanding the durability of these devices. The present study reports the midterm outcomes of a single-center experience using the Zenith Alpha thoracic endovascular stent graft.

METHODS

The outcomes of 270 procedures performed on 262 patients (197 men; mean age, 70.5 ± 9.5 years) using the Zenith Alpha thoracic endovascular stent graft from November 2013 to December 2019 for different thoracic aortic diseases were analyzed. The primary endpoints were 30-day clinical success and midterm (5-year) clinical success. The secondary endpoints were the adverse event rate at 30 days and midterm and access- and device-related complications. The follow-up of surviving patients was performed using computed tomography angiography and office visits at 1, 6, and 12 months and annually thereafter. Kaplan-Meier analysis was performed for overall survival, and freedom from thoracic aortic endovascular repair-related mortality and related reinterventions.

RESULTS

The overall 30-day mortality was 5.2% (2.5% for elective and 30.8% for nonelective cases). Type I endoleaks were identified in six patients. The 30-day primary technical and clinical success rates were 97.8% and 92.6%, respectively. Femoral cutdown was used in 41.1% of cases and percutaneous access in 58.5%. The rate of femoral artery complications after the percutaneous approach was 5.1%, with the need for surgical conversion in 1.9%. The stroke rate was 4.1% (major stroke, 2.2%), and the spinal cord ischemia rate was 3.7% (permanent paraplegia, 0.7%). Of the 248 survivors, 239 complied with the follow-up protocol with adequate computed tomography angiograms available images. Overall follow-up survival was 94.0% at 1 year, 91.6% at 2 years, 88.9% at 3 years, and 88.5% at 5 years. The unplanned secondary endovascular procedure rate was 5.3%. No stent fractures or new-onset type I endoleaks due to stent graft migration were observed in the study cohort.

CONCLUSIONS

The midterm outcomes of this new generation of low-profile devices were satisfactory. The reported low incidence of secondary procedures and the absence of migrations are promising for the long-term durability of these devices.

A Modified Proximal Stent-Graft for Spinal Cord Preconditioning During Staged Endovascular Repair of Thoracoabdominal Aortic Aneurysms

Purpose: To describe a new custom-made thoracic device able to seal against the aortic wall and occlude intercostal arteries for spinal cord preconditioning during the first thoracic stage of a thoracoabdominal endovascular repair. Technique: The custom-made device, based on the Zenith Alpha stent-graft, combines different features from 2 previously described devices: the outer part is designed with a bell-bottom configuration similar to the “Embo” stent-graft, while the inner part mimics the “2 in 1” design. The outer stent-graft is designed to span the entire length of the thoracic aorta and cover as many intercostal arteries as possible during the first stage to effectively precondition the spinal cord. The sutured inner component is customizable in diameter and 20 to 40 mm shorter than the outer stent-graft. The technique has been used in 5 patients. Conclusion: The use of this new custom-made thoracic stent-graft might represent an additional tool for effectively preconditioning the spinal cord during fenestrated and branched staged procedures whenever a proximal thoracic proximal component is needed.

Postimplantation Syndrome Is Not Associated with Myocardial Injury after Noncardiac Surgery after Endovascular Aneurysm Repair

BACKGROUND

Postimplantation syndrome (PIS) is the clinical and biochemical expression of an inflammatory response following endovascular aneurysm repair (EVAR), with a reported incidence ranging from 2% to 100%. Although generally benign, some studies report an association between PIS and postoperative major adverse cardiovascular events (MACEs). Nonetheless, the role of PIS in postoperative myocardial injury after noncardiac surgery (MINS) is unknown. This work aims to evaluate the relationship between PIS and MINS in a subset of EVAR patients, as well as assess the impact of PIS in all-cause mortality.

METHODS

All patients undergoing elective standard EVAR between January 2008 and June 2017, and with at least one measurement of contemporary (cTnI) or high sensitivity troponin I (hSTnI) in the first 48h after surgery, were retrospectively analyzed. PIS was defined as the presence of fever and leukocytosis in the postoperative period in the absence of infectious complications. MINS was defined as the value exceeding the 99th percentile of a normal reference population with a coefficient of variation <10%, which was >0.032 ng/mL for cTnI and 0.0114 (female) and 0.027 ng/mL (male) for hSTnI. Patients' demographics, comorbidities, medication, access, and anesthesia were also evaluated.

RESULTS

One hundred thirty-three consecutive patients were included (95.5% male; mean age 75.66 ± 7.13 years). Mean follow-up was 46.35 months. Survival rate was 86.5%, 80.5%, and 57.6% at 1, 3, and 5 years of follow-up, with 2 fatalities at 30 days of follow-up. The prevalence of PIS was 11.4%. MACE occurred in 2.3% of the patients, while MINS was reported in 16.5% of the patients. No association was found between PIS and patients' gender, comorbidities, type of anesthesia, or transfusional support. The type of graft used significantly affected the prevalence of PIS, with all cases reported when polyester grafts were used (P = 0.031). MACE occurred in 2.3% of the patients, while MINS was reported in 16.5% of the patients. PIS was found to be significantly associated with postoperative MACE (P = 0.001), but not MINS. Survival analysis revealed no differences between patients with or without PIS regarding 30-day mortality as well as long-term all-cause mortality. American Society of Anesthesiologists score (hazard ratio [HR] 2.157, 95% confidence interval [CI] 1.07-4.33, P = 0.031) and heart failure (HR 2.284, 95% CI 1.25-4.18, P = 0.008) were found to be independently associated with increased long-term all-cause mortality in this cohort of patients.

CONCLUSIONS

PIS is a common complication after EVAR, occurring in 11.4% of the patients from this cohort. Graft type seems to significantly affect the risk of PIS, since all reported cases occurred when polyester grafts were used. PIS did not influence 30-day or long-term survival and was found to be significantly associated with postoperative MACE but not MINS, suggesting the involvement of different pathophysiological mechanisms.

National Trends of Thoracic Endovascular Aortic Repair versus Open Thoracic Aortic Repair in Pediatric Blunt Thoracic Aortic Injury

BACKGROUND

Blunt thoracic aortic injury (BTAI) occurs in <1% of all trauma admissions. Thoracic endovascular aortic repair (TEVAR) has become the preferred treatment modality in adult patients with BTAI, but its use in pediatrics is currently not supported by device manufacturers and lacks United States Food and Drug Administration approval. We hypothesized that there would also be an increased use of TEVAR in the pediatric population, thus conferring a lower risk of mortality compared with open thoracic aortic repair (OTAR).

METHODS

The National Trauma Data Bank (2007-2015) was queried for patients ≤17 years with BTAI. The primary outcomes were the incidences of TEVAR and OTAR. Secondary outcome was risk of mortality in those undergoing intervention. A multivariable logistic regression model was used to determine the risk of mortality in OTAR versus TEVAR.

RESULTS

We identified 650 pediatric BTAI patients with 159 (24.5%) undergoing intervention. Of these, 124 underwent TEVAR (78.0%) and 35 (22.0%) underwent OTAR. The rate of TEVAR steadily increased from 2007 to 2015 (15.4% vs. 27.1%, P < 0.001). Patients receiving OTAR and TEVAR had a similar injury severity score and rate of hypotension on admission (P > 0.05). Compared with OTAR, TEVAR patients had a higher rate of any traumatic brain injury (TBI) (63.7% vs. 37.1%, P = 0.005) and shorter hospital and intensive care unit length of stay (LOS) (16.4 vs. 21.4 days, P = 0.02; 10.1 vs. 12.2 days, P = 0.01). TEVAR and OTAR, even when stratified by ≤14 years and 15-17 years, had no difference in risk for mortality (odds ratio 1.20, confidence interval 0.29-5.01, P = 0.80).

CONCLUSIONS

The rate of TEVAR in pediatric BTAI nearly doubled from 2007 to 2015. Compared with OTAR, TEVAR was associated with a shorter hospital LOS despite a higher rate of TBI. There was no difference in risk for mortality between TEVAR and OTAR. Longitudinal studies to determine the long-term efficacy and complication rates, including reintervention, development of endoleak, and/or need for further operations, are needed as this technology is being rapidly adopted for pediatric trauma patients.

Durability of a low-profile stent graft for thoracic endovascular aneurysm repair

OBJECTIVE

The introduction of lower profile endografts expanded the application of aortic endovascular repair. However, evidence about their durability is still scarce. The objective of this study was to assess longer term durability of the Zenith Alpha Thoracic Stent Graft (Cook Inc, Bloomington, Ind) after thoracic endovascular aortic repair.

METHODS

Prospectively collected data of all patients treated for thoracic aortic aneurysms or penetrating aortic ulcers and having computed tomography angiography-based follow-up of ≥12 months were retrospectively analyzed. The primary end point was ongoing clinical success. Among the secondary end points, stent graft migration and fracture were analyzed.

RESULTS

Between August 2010 and October 2015, 70 consecutive patients were treated in a single center with the Zenith Alpha stent graft. With computed tomography angiography-based follow-up of 22.3 ± 15.9 months, ongoing clinical success was 87.1%. There were three cases of type IA endoleak (4.3%), two cases of type IB endoleak (2.9%), and one case of aneurysm sac enlargement (1.4%). Five patients died postoperatively (7.1%). No type III or type IV endoleak was detected; there was one case of distal stent graft migration and no stent fracture. Reintervention was necessary in one case (1.4%) of a combined type IA and type II endoleak. There were no conversions to open repair and no ruptures or intraoperative deaths. All-cause mortality was 17.1% at 76 months.

CONCLUSIONS

The Zenith Alpha Thoracic Stent Graft appears to maintain favorable results in a longer time frame with a low incidence of aneurysm sac growth and migration. Results from multicenter prospective trials are needed to validate these data.