Protected and Unprotected Radiation Exposure to the Eye Lens During Endovascular Procedures in Hybrid Operating Rooms.

OBJECTIVE: Radiation cataract has been observed at lower doses than previously thought, therefore the annual limit for equivalent dose to the eye lens has been reduced from 150 to 20 mSv. This study evaluated radiation exposure to the eye lens of operators working in a hybrid operating room before and after implementation of a dose reduction program. METHODS: From April to October 2019, radiation exposure to the first operator was measured during all consecutive endovascular procedures performed in the hybrid operating room using BeOSL Hp(3) eye lens dosimeters placed both outside and behind the lead glasses (0.75 mm lead equivalent). Measured values were compared with data from a historic control group from the same hospital before implementation of the dose reduction program. RESULTS: A total of 181 consecutive patients underwent an endovascular procedure in the hybrid operating room. The median unprotected eye lens dose (outside lead glasses) of the main operator was 0.049 mSv for endovascular aortic repair (EVAR) (n = 30), 0.042 mSv for thoracic endovascular aortic repair (TEVAR) (n = 23), 0.175 mSv for complex aortic fenestrated or branched endovascular procedures (F/BEVAR; n = 15), and 0.042 mSv for peripheral interventions (n = 80). Compared with the control period, EVAR had 75% lower, TEVAR 79% lower, and F/BEVAR 55% lower radiation exposure to the unprotected eye lens of the first operator. The lead glasses led to a median reduction in the exposure to the eye lens by a factor of 3.4. CONCLUSION: The implementation of a dose reduction program led to a relevant reduction in radiation exposure to the head and eye lens of the first operator in endovascular procedures. With optimum radiation protection measures, including a ceiling mounted shield and lead glasses, more than 440 EVARs, 280 TEVARs, or 128 FEVARs could be performed per year before the dose limit for the eye lens of 20 mSv was reached.

Dynamic Morphology of the Ascending Aorta and Its Implications for Proximal Landing in Thoracic Endovascular Aortic Repair.

In this study, we assessed the dynamic segmental anatomy of the entire ascending aorta (AA), enabling the determination of a favorable proximal landing zone and appropriate aortic sizing for the most proximal thoracic endovascular aortic repair (TEVAR). Methods: Patients with a non-operated AA (diameter < 40 mm) underwent electrocardiogram-gated computed tomography angiography (ECG-CTA) of the entire AA in the systolic and diastolic phases. For each plane of each segment, the maximum and minimum diameters in the systole and diastole phases were recorded. The Wilcoxon signed-rank test was used to compare aortic size values. Results: A total of 100 patients were enrolled (53% male; median age 82.1 years; age range 76.8−85.1). Analysis of the dynamic plane dimensions of the AA during the cardiac cycle showed significantly higher systolic values than diastolic values (p < 0.001). Analysis of the proximal AA segment showed greater distal plane values than proximal plane values (p < 0.001), showing a reversed funnel form. At the mid-ascending segment, the dynamic values did not notably differ between the distal plane and the proximal segmental plane, demonstrating a cylindrical form. At the distal segment of the AA, the proximal plane values were larger than the distal segmental plane values (p < 0.001), thus generating a funnel form. Conclusions: The entire AA showed greater systolic than diastolic aortic dimensions throughout the cardiac cycle. The mid-ascending and distal-ascending segments showed favorable forms for TEVAR using a regular cylindrical endograft design. The most proximal segment of the AA showed a pronounced conical form; therefore, a specific endograft design should be considered.

Acute Stanford type B aortic dissection-who benefits from genetic testing?

BACKGROUND: Stanford type B aortic dissection is a rare, life-threatening complex phenotype associated with several modifiable and genetic risk factors. In the current study of a hospital-based, consecutive series of aortic dissection patients we propose a selection based on age and family history of aortic disease for genetic testing and detection of causative gene variants. METHODS: In this single center cohort study from 2013 to 2018 patients with acute Stanford type B aortic dissections were consecutively treated and analyzed by next generation sequencing based on selection criteria (age of disease onset ≤45 years and/or positive familial history for aortic disease) to detect genome-wide pathogenic variants in protein-coding sequences and to identify large copy number variants (CNV). Variants in a predefined panel of 30 genes associated with the familial thoracic aortic aneurysm and dissection (TAAD) syndrome were evaluated. RESULTS: From 105 patients nine matched selection criteria for genetic testing. Next-generation sequencing analysis revealed causal variants in FBN1 (fibrillin-1) in three patients: a pathogenic missense variant [c.6661T>C, p.(Cys2221Arg)] and two truncating variants [c.4786C>T, p.(Arg1596Ter)] and [c.6366C>CA, p.(Asp2123GlufsTer5)]. A fourth patient carried a large (>1,000,000 bp) CNV in the long arm of chromosome 10, deleting eleven genes, including the whole ACTA2 (actin alpha 2) gene. The latter two genetic findings have not been reported before. CONCLUSIONS: Selection of patients on the basis of young age and familial inheritance of aortic disease favors the identification of disease-causing genetic variants in a clinical cohort of patients with Stanford type B aortic dissection.

Distal Stent Graft-Induced New Entry After TEVAR or FET: Insights Into a New Disease From EuREC.

BACKGROUND: The study sought to learn about incidence and reasons for distal stent graft-induced new entry (dSINE) after thoracic endovascular aortic repair (TEVAR) or after frozen elephant trunk (FET) implantation, and develop prevention algorithms. METHODS: In an analysis of an international multicenter registry (EuREC [European Registry of Endovascular Aortic Repair Complications] registry), we found 69 dSINE patients of 1430 (4.8%) TEVAR patients with type B aortic dissection and 6 dSINE patients of 100 (6%) patients after the FET procedure for aortic dissection with secondary morphological comparison. RESULTS: The underlying aortic pathology was acute type B aortic dissection in 33 (44%) patients, subacute or chronic type B aortic dissection in 34 (45%) patients, acute type A aortic dissection in 3 patients and remaining dissection after type A repair in 3 (8%) patients, and acute type B intramural hematoma in 2 (3%) patients. dSINE occurred in 4.4% of patients in the acute setting and in 4.9% of patients in the subacute or chronic setting after TEVAR. After the FET procedure, dSINE occurred in 5.3% of patients in the acute setting and in 6.5% of patients in the chronic setting. The interval between TEVAR or FET and the diagnosis of dSINE was 489 ± 681 days. Follow-up after dSINE was 1340 ± 1151 days, and 4 (5%) patients developed recurrence of dSINE. Morphological analysis between patients after TEVAR with and without dSINE showed a smaller true lumen diameter, a more accentuated oval true lumen morphology, and a higher degree of stent graft oversizing in patients who developed dSINE. CONCLUSIONS: dSINE after TEVAR or FET is not rare and occurs with similar incidence after acute and chronic aortic dissection (early and late). Avoiding oversizing in the acute and chronic settings as well as carefully selecting patients for TEVAR in postdissection aneurysmal formation will aid in reducing the incidence of dSINE to a minimum.

Endograft migration after thoracic endovascular aortic repair.

OBJECTIVE: The objective of this study was to evaluate the incidence, timing, and potential risk factors of late endograft migration after thoracic endovascular aortic repair (TEVAR). METHODS: A retrospective analysis was conducted of 123 patients receiving TEVAR for thoracic aortic aneurysms (TAAs), dissections, penetrating aortic ulcer, intramural hematoma, or traumatic transection between January 2005 and December 2015 with a minimum imaging-based follow-up of 6 months. Imaging analysis was performed by three independent readers. Migration was defined according to the reporting standards as a stent graft shift of >10 mm relative to a primary anatomic landmark or any displacement that led to symptoms or required therapy. A standardized measurement protocol in accordance with the reporting guidelines was used. Median follow-up was 3 years (range, 0.5-10 years). RESULTS: Migration occurred in nine (7.3%) patients and took place at the proximal landing zone (n = 1), overlapping zone (n = 4), or distal landing zone (n = 5), resulting in type I or type III endoleaks in 44% (n = 4/9) of the cases. All cases of migration with endoleaks underwent reintervention; 75% (n = 3/4) of the migration associated with endoleaks could have been identified on previous imaging before an endoleak occurred. Freedom from migration was 99.1% after 1 year, 94.0% after 3 years, and 86.1% after 5 years. Aortic elongation and TAA were identified as predisposing factors for migration (P = .003 and P = .01, respectively). No influence of the proximal landing zone (zone 0-4), type of aortic arch (I-III), or type of endograft on the incidence of migration was found. CONCLUSIONS: Graft migration after TEVAR occurs in a relevant proportion of patients, predominantly in patients with TAA and aortic elongation. Follow-up imaging of these patients should be specifically evaluated regarding the occurrence of migration.

Prevalence of the Computed Tomographic Morphological DISSECT Predictors in Uncomplicated Stanford Type B Aortic Dissection.

OBJECTIVE/BACKGROUND: The aim was to analyse the prevalence of computed tomographic (CT) morphological predictors and their influence on early chronic phase aortic diameter expansion in patients with uncomplicated acute Stanford type B aortic dissection (ATBAD). METHODS: This retrospective analysis reviewed the CT imaging of 140 patients admitted with uncomplicated ATBAD to two tertiary centres between March 2003 and April 2016. The prevalence of the following CT-morphological predictors was determined at baseline: primary entry tear (PET) diameter ≥ 10 mm, its location at the concavity of the aortic arch; maximum descending aortic diameter ≥ 40 mm; false lumen (FL) diameter ≥ 22 mm; partial FL thrombosis and a fusiform index (FI) of ≥0.64. Thoracic aortic diameter expansion (ADE) was evaluated in 65 patients treated by best medical therapy (BMT) (median CT follow up 11.6 months). Study end points were predictor prevalence and ADE. RESULTS: A mean ± SD of 2.45 ± 1.35 predictors were registered among all 140 patients; 75.0% of patients showed at least two predictors. In 7.9% of patients, no predictor was found. The prevalence of PET at the arch concavity was 18.6%, PET diameter ≥10 mm in 60.0%, maximal descending aortic diameter ≥40 mm in 51.4%, FL diameter ≥22 mm in 47.9%, partial FL thrombosis in 47.9%, and FI ≥ 0.64 in 20.7%. An ADE ≥5 mm was observed in 38 of 65 patients. Median observed ADE was 5.1 mm (median follow up (FU) 11.6 months, range -3.2-27.4 mm). Regression analysis for multiple predictors showed a basic ADE of 2.5 mm plus 1.9 mm per predictor at the median FU of 11.6 months (2.5 mm ± 1.9; 95% confidence interval CI -0.2-5.2 mm ± 0.7-3.0 mm; p = .003). CONCLUSION: In the majority of patients, at least one of the investigated morphological predictors of disease progression in uncomplicated ATBAD was detected. An ADE ≥5 mm affected 38 of 65 BMT patients. CT based predictors help to define TBAD patients at risk of progression.

Prevalence of Bovine Aortic Arch Variant in Patients with Aortic Dissection and its Implications in the Outcome of Patients with Acute Type B Aortic Dissection.

OBJECTIVE/BACKGROUND: To investigate the prevalence of bovine arch (BA) among patients with type A and B aortic dissection, and to provide insight into the implication of this variation on the outcome of patients with acute or subacute type B aortic dissection (a/sTBAD). METHODS: This retrospective cohort analysis includes patients with a/sTBAD admitted between January 2006 and December 2016. Computed tomographic angiograms (CTAs) of patients referred because of type A aortic dissection were also re-evaluated with regard to the presence of BA. As a control group, 110 oncological patients who had undergone a chest CTA for disease staging during the study period were enrolled. A total of 154 patients with a/sTBAD and 168 with type A aortic dissection were identified during the study period. RESULTS: An overall prevalence of 17.6% for BA variants was revealed. The comparison between patients with aortic dissection and the control group showed no statistically significant difference in BA prevalence (17.7% vs. 17.3%; p = 1.0). No statistically significant difference in BA prevalence was observed when comparing patients with type A aortic dissection with those with type B aortic dissection (16.6% vs. 18.8%; p = .66). During a median follow-up period of 27.8 months, 30 patients died. The mortality rate among patients presenting a BA variant was 34.5%, whereas among patients without, it was 16.0% (p = .04). Multivariate analysis revealed the presence of a BA as an independent predictor of mortality (adjusted odds ratio 3.4, 95% confidence interval 1.2-9.8). CONCLUSION: The BA should be considered as a predictor of the outcome for patients with type B aortic dissection.

Outcome of thoracic endovascular aortic repair in patients with thoracic and thoracoabdominal aortic aneurysms.

OBJECTIVE: This study reports the long-term results after thoracic endovascular aortic repair (TEVAR) in thoracic aortic aneurysms (TAAs) and thoracoabdominal aortic aneurysms (TAAAs). METHODS: Between 1997 and 2010, 269 patients were treated with TEVAR, 100 of them (72 male; mean age, 68.3 years) for aneurysmal disease. An intact TAA (iTAA) was present in 49 patients and an intact TAAA (iTAAA) in 18. In 25 patients, there was a ruptured TAA or ruptured TAAA (rTAA). Eight patients were admitted with a post-traumatic TAA (pTAA). Retrospective analysis was performed from a prospectively maintained database. Primary end points were 5-year all-cause and TEVAR-related mortality. Secondary end points were causes of death, complications, and reinterventions (RIs). A 5-year follow-up was complete in all cases. RESULTS: The overall 5-year mortality rate was 50% (40.8% in iTAA, 80% in rTAA, 12.5% in pTAA, and 50% in iTAAA, respectively; log-rank test, P = .00012). The overall procedure-related mortality was 21% (10.2% [n = 5] in iTAA, 40% [n = 10] in rTAA, 33% [n = 6] in iTAAA, and 0 in pTAA, respectively; log-rank test, P = .00013). Freedom from complication was 52%, 47.2%, and 47.2% at 1, 3, and 5 years, respectively. There were a total of 30 RIs in 25 patients. Freedom from RI was 82%, 77.8%, and 71.2% at 1, 3, and 5 years. Stepwise forward logistic regression analysis revealed rTAA and occurrence of complications were risk factors for survival (odds ratios, 7.7 and 4.2, respectively). CONCLUSIONS: Long-term results after TEVAR for aneurysmatic aortic disease demonstrate considerable overall and procedure-related mortality in both elective and urgent indications. Complications and RIs occur still as late events and emphasize the necessity for long-term follow-up.