Philipp Geisbüsch

Hybrid procedures for thoracoabdominal aortic aneurysms and chronic aortic dissections – A single center experience in 28 patients

OBJECTIVE We report our 6-year experience with the visceral hybrid procedure for high-risk patients with thoracoabdominal aortic aneurysms (TAAA) and chronic expanding aortic dissections (CEAD). METHODS Hybrid procedure includes debranching of the visceral and renal arteries followed by endovascular exclusion of the aneurysm. A series of 28 patients (20 male, mean age 66 years) were treated between January 2001 and July 2007. Sixteen patients had TAAAs type I-III, one type IV, four thoracoabdominal placque ruptures, and seven patients CEAD. Patients were treated for asymptomatic, symptomatic, and ruptured aortic pathologies in 20, and 4 patients, respectively. Two patients had Marfans syndrome; 61% had previous infrarenal aortic surgery. The infrarenal aorta was the distal landing zone in 70%. In elective cases, simultaneous approach (n = 9, group I) and staged approach (n = 11, group II) were performed. Mean follow-up is 22 months (range 0.1-78). RESULTS Primary technical success was achieved in 89%. All stent grafts were implanted in the entire thoracoabdominal aorta. Additionally, three patients had previous complete arch vessel revascularization. Left subclavian artery was intentionally covered in three patients (11%). Thirty-day mortality rate was 14.3% (4/28). One patient had a rupture before the staged endovascular procedure and died. Overall survival rate at 3 years was 70%, in group I 80%, and in group II 60% (P = .234). Type I endoleak rate was 8%. Permanent paraplegia rate was 11%. Three patients required long-term dialysis (11%). Peripheral graft occlusion rate was 11% at 30 days. Gut infarction with consecutive bowel resection occurred in two patients. There was no significant difference between group I and II regarding paraplegia and complications. CONCLUSIONS Early results of visceral hybrid repair for high-risk patients with complex and extended TAAAs and CEADs are encouraging in a selected group of high risk patients in whom open repair is hazardous and branched endografts are not yet optional.

Short and midterm results after left subclavian artery coverage during endovascular repair of the thoracic aorta

BACKGROUND To analyze the sequelae of the intentional left subclavian artery (LSA) coverage during thoracic endovascular aortic repair (TEVAR). METHODS Retrospective analysis of prospectively collected data in a single center. Between March 1997 and October 2008, 88 of 220 patients (40%) had thoracic aortic lesions that required LSA coverage during TEVAR. Thirty-four of our patients (39%) were treated under urgent or emergent conditions for acute pathologies. The proximal landing zone was zone 0 in 10 patients (11%), zone 1 in 24 patients (27%), and zone 2 in 54 patients (61%). Debranching procedures of the supra-aortic vessels were performed in patients who were to undergo zone 0 or zone 1 deployment. Primary LSA revascularization was performed in 22 of the 88 patients (25%) at a median of 6 days before TEVAR. Median follow-up was 26.4 months (1-98 months). RESULTS Technical success was achieved in 97%. Five primary (9%) and two secondary (4%) type Ia endoleaks in patients who underwent zone 2 deployment were observed and required further interventions. Fourteen (16%) primary type II endoleaks were observed; 10 of them fed by the LSA. Paraplegia rate was lower in patients with LSA coverage without revascularization than in other patients (1.5% vs 1.9%; odds ratio [OR], 0.774; 95% confidence interval [CI], 0.038-6.173; P = 1.000). Prior or concomitant infrarenal aortic replacement (P = .0019), renal insufficiency (glomerular filtration rate < 90 mL/min/1.73 m(2)) (P = .0024) and long segment aortic coverage (>200 mm) (P = .0157) were associated with significant higher risk of postoperative paraplegia. Stroke rate was lower in patients with LSA coverage without revascularization than in other patients (3% vs 3.9%; OR, 0.570; 95% CI, 0.118-2.761; P = .7269). Two patients (3%) developed left upper extremity symptoms and another two patients (3%) subclavian steal syndrome and required secondary LSA revascularization. The technical success rate for LSA revascularization was 94%. CONCLUSION By using a selective approach to the LSA revascularization, coverage of the LSA can be used to extend the proximal seal zone for TEVAR without increasing the risk of spinal cord ischemia or stroke. Indications for revascularization include long segment aortic coverage, prior or concomitant infrarenal aortic replacement, and renal insufficiency. In addition, a hypoplastic right vertebral artery, a patent left internal mammary artery graft, and a functioning dialysis fistula in the left arm would also be indications to perform revascularization.

Complications after aortic arch hybrid repair

OBJECTIVES To analyze early and midterm complications after hybrid aortic arch repair (HAR). METHODS Between January 1997 and November 2009 among 259 patients receiving thoracic endovascular aortic repair, HAR has been performed in 47 patients (median age, 64.5 years; range, 41-84). A retrospective analysis was performed. Complete supra-aortic debranching was performed in 15 patients (32%) and partial debranching in 23 patients (49%). Isolated left subclavian artery revascularization prior to thoracic endovascular aortic repair has been used in nine patients (19%). Emergency procedures were performed in 34% of all patients. RESULTS The overall in-hospital mortality was 19% (9/47 patients), 27% after complete and 15.6% after partial debranching. Postoperative complications occurred in 32 patients (68%). Cardiocirculatory complications were observed in seven patients (15%). Pulmonary complications occurred in 12 patients (26%). A total of five patients (11%) experienced renal complications requiring hemodialysis. The stroke rate was 6.3%. Paraplegia was seen in three patients (6%). Proximal type I endoleaks were observed in seven patients. Retrograde aortic arch dissection was seen in three patients (6.3%). Cox proportional hazard regression showed the necessity for an emergency procedure as an independent predictor of death (hazard ratio, 2.9; 95% confidence interval, 1.1-7.5; P = .023). The reintervention rate was 27.6% with three patients requiring open conversion. CONCLUSIONS Hybrid aortic arch repair in high-risk patients is associated with a relevant morbidity, mortality, and reintervention rate. Patient selection is crucial and indication should be limited to patients not suitable for conventional aortic arch repair or emergency cases at present. Therefore, we recommend performing HAR only in high-volume centers with cardiovascular surgical cooperation.

Endovascular Treatment of Visceral and Renal Artery Aneurysms

PURPOSE To analyze early and midterm results of endovascular treatment of visceral aneurysms regarding technical considerations, technical success rate, aneurysm rupture, and end-organ ischemia. MATERIALS AND METHODS Endovascular treatment of 41 visceral and renal artery aneurysms (VAAs) in 40 consecutive patients (25 women; mean age, 59.4 y ± 16.2) was retrospectively reviewed. The series included 30 true aneurysms and 11 pseudoaneurysms in renal (n = 17), splenic (n = 13), hepatic (n = 4), celiac (n = 4), gastroduodenal (n = 2), and middle colic (n = 1) arteries. Demographic, clinical, procedural, and follow-up data were analyzed. RESULTS Forty-one aneurysms underwent endovascular treatment. Hypertension (73%) and hyperlipidemia (32%) were the most common associated comorbidities. Nineteen patients presented with symptoms of pain (15%) or rupture (32%) in 10 pseudoaneurysms (91%) and nine true aneurysms (30%; P = .0007). The most commonly used technique (93%) was coil embolization with (15%) or without (78%) other endovascular agents. The rate of technical success (cessation of hemorrhage or blood flow into aneurysm sac) was 98%. There was no periprocedural mortality. Mean hospital stays were 1 and 2 days for asymptomatic and symptomatic patients, respectively. Mean clinical follow-up was 44.5 months; mean imaging follow-up was 11.7 months. The only complication was an intraprocedural thromboembolic event in one case (3%). Follow-up imaging evidence of end-organ partial infarct was detected in six patients (21%), with no clinical evidence of organ insufficiency. CONCLUSIONS Endovascular treatment of VAAs is a safe and highly successful procedure. Associated side effects such as distal embolization and end-organ infarcts were not found to be clinically significant.

Total vs hemi-aortic arch transposition for hybrid aortic arch repair.

OBJECTIVE To compare the outcomes of total aortic arch transposition (TAAT) vs hemi-aortic arch transposition (HAAT) for hybrid aortic arch repair. METHODS A systematic search was performed using PubMed between November 1998 and May 2010 by two independent observers. Studies included reporting on patients treated by TAAT or HAAT and stent grafting in a proximal landing zone 0 or 1 by Ishimaru, respectively. Further articles were identified by following MEDLINE links, by cross-referencing from the reference lists, and by following citations for these studies. Case reports and case series of less than five patients were excluded. Primary technical and initial clinical success, perioperative, and late morbidity and mortality were extracted per study and were meta-analyzed. RESULTS Fourteen studies were included in the statistical analysis. The number of reported patients totaled 130 for TAAT/zone 0 and 131 for HAAT/zone 1. The primary technical success rate was significantly higher in zone 0 than 1 (95% vs 83%; odds ratio [OR], 4.0; 95% confidence interval [CI], 1.47-10.88; P = .0069), due to significantly higher primary type I or III endoleak rates in zone 1 (15.48% vs 3.97%; P = .0050). Reintervention rates were significantly higher in zone 1 (25.81% vs 12.00%; P = .0321). Initial clinical success rates were comparable between zone 0 and 1 (88% vs 85%; OR, 1.35; 95% CI, 0.61-3.02; P = .5354). In-hospital mortality was higher in zone 0 than 1 (8.46% vs 4.58%; P = .2212). CONCLUSION The more invasive TAAT allows a better landing zone at the cost of higher perioperative mortality, therefore, patient selection is crucial.

Reinterventions during midterm follow-up after endovascular treatment of thoracic aortic disease

OBJECTIVES To report incidence, indication, and timing of reinterventions after thoracic endovascular aortic repair (TEVAR) and identify subgroups most prone to reinterventions. METHODS Between January 1997 and March 2010, a total of 264 patients received TEVAR in our institution. During follow-up, 58 patients (39 men, median age 63 years, range 28-87 years) required a total of 68 reinterventions, which represent the study population of this retrospective, single center analysis. The mean follow-up of all 264 patients was 31.2 months (range 0-141 months). RESULTS The overall reintervention rate was 22%: 1-, 3-, and 5-year free reintervention rates were 82% ± 3%, 74% ± 3%, and 70% ± 4%, respectively. Indications for reintervention were predominately endoleaks (41%) and progression of the underlying aortic disease (29%). Reinterventions were performed by endovascular means in 44%, by open repair in 35% (including 11 conversions), and by hybrid procedures in 21%. Multiple logistic regression analysis revealed patients with chronic expanding aortic dissections (odds ratio [OR]: 2.35), hybrid aortic procedures (OR: 2.11), and connective tissue diseases (OR: 7.54) at an increased risk for reintervention. The necessity for reintervention did not influence survival in this cohort (log-rank test P = .1706). CONCLUSIONS TEVAR is associated with a relevant reintervention rate, predominately caused by endoleaks and progression of the aortic pathology. Patients with chronic expanding aortic dissections, hybrid aortic procedures, and connective tissue diseases are at an increased risk for reintervention and should therefore undergo close follow-up.

Reproducibility of deriving parameters of AAA rupture risk from patient-specific 3D finite element models.

Purpose To assess the reproducibility of estimating biomechanical parameters of abdominal aortic aneurysms (AAA) based on finite element (FE) computations derived from a commercially available, semiautomatic vascular analyzer that reconstructs computed tomographic angiography (CTA) data into FE models. Methods The CTA data from 10 consecutive male patients (mean age 74 years, range 63–87) with a fusiform infrarenal AAA >5 cm in diameter were used for this study, along with the CTA scans from 4 individuals without aortic disease. Three different observers used semiautomatic reconstruction software to create deformable contour models from axial CT scans. These 3-dimensional FE models captured the aortic wall and thrombus tissue using isotropic finite strain constitutive modeling. Geometric (maximum diameter and volume measurements based on an anatomical centerline) and biomechanical determinants [aneurysm peak wall stress (PWS) and the peak wall rupture risk (PWRR) index] were then calculated from the FE models. The determinations were made 5 times for each anonymized dataset presented for analysis in random order (5-fold measurements for 14 datasets produced 210 measurements from the 3 observers). Inter- and intraobserver variability were assessed by calculating the coefficient of variation of these repeated measures. The methodological variations were expressed with the intraclass correlation coefficient (ICC) and Bland-Altman plots. Results The median segmentation time was <1 hour (mean 39.2 minutes, range 25–48) for datasets from the AAA patients; for the healthy individuals, segmentation times were considerably shorter (median 8.7 minutes, range 4–15). Intraobserver reproducibility was high, as represented by a CV <3% for the diameter measurement and <5.5% for volume, PWS, and the PWRR index. The ICC was 0.97 (range 0.95–0.98) for diameter and 0.98 (range 0.97–0.99) for volume; for PWS and the PWRR index, the ICCs were equal at 0.98 (range 0.97–0.99). Conclusion The reproducibility of volume and maximum diameter measurements in infrarenal AAAs with FE analysis is high. With the model used in this semiautomatic reconstruction software, wall stress analysis can be achieved with high agreement among observers and in serial measurements by a single observer.

Early and midterm results after endovascular stent graft repair of penetrating aortic ulcers

PURPOSE To present early and midterm results after endovascular stent graft repair of patients with penetrating aortic ulcers (PAU). METHODS Between January 1997 and March 2008, a total of 202 patients received thoracic aortic endografting in our institution, 48 patients (32 men, median age 70 years, range, 48-89) with PAU. A retrospective analysis of these patients was performed. Thirty-one patients (65%) showed an acute aortic syndrome (8 contained rupture, 23 symptomatic). Follow-up scheme included postoperative computed tomography angiography prior to discharge, at 3, 6, and 12 months, and yearly thereafter. Mean follow-up was 31.3 months (1.3-112.6). RESULTS Technical success was achieved in 93.7%. Primary clinical success rate was 81.2%. In-hospital mortality was 14.6%. Perioperative mortality was significantly (P = .036) higher in patients with acute aortic syndrome compared to asymptomatic patients (22.5% vs 0%). Postoperative complications occurred in 15 patients (31%), including 2 patients with minor strokes and 6, respectively, 5 patients with cardiac and/or respiratory complications. Early endoleaks were observed in 9 patients (19%), late endoleaks in another 2 patients. Reintervention was necessary in 4 out of 48 patients (8.4%). The actuarial survival estimates at 1, 3, and 5 years were 78% +/- 6%, 74% +/- 7%, and 61% +/- 10%, respectively. There was no aortic-related death during follow-up. Cox regression showed age (hazard ratio [HR]; 1.08, P = .036) and a maximum aortic diameter >50 mm (HR, 4.92; P = .021) as independent predictors of death. CONCLUSION Endovascular treatment of penetrating aortic ulcers is associated with a relevant morbidity and mortality rate in frequently highly comorbid patients. Midterm results could prove a sustained treatment success regarding actuarial survival and aortic-related death. Emergencies show a significantly worse outcome, but treatment is still warranted in these symptomatic patients.

Direct percutaneous sac injection for postoperative endoleak treatment after endovascular aortic aneurysm repair

BACKGROUND This study presents the short-term and midterm results of direct percutaneous sac injection (DPSI) for postoperative endoleak treatment after endovascular aortic aneurysm repair (EVAR). METHODS Between March 1994 and November 2011, EVAR was performed in 986 patients. The median follow-up was 63 ± 45 months (range, 0-211 months). A retrospective analysis was performed. DPSI was used in 21 patients for 19 type II endoleaks and two endoleaks of undefined origin (EOUO), of which 12 (57%) were after failure of a previous endovascular treatment attempt. RESULTS DPSI using thrombin (n = 16), coils (n = 7), gelfoam (n = 6), or glue (n = 3), or a combination, was technically feasible in all patients. Saccography during DPSI revealed a previously undetected type I endoleak in three patients. Immediate DPSI success was achieved in 16 of 18 procedures (88.9%), with two complications. Glue incidentally intravasated in the inferior vena cava, causing a clinically nonsignificant subsegmental pulmonary artery embolism in one patient, and the temporary development of a type III endoleak, possibly from graft puncture, in another. During a median follow-up of 39 months (interquartile range, 13-88 months) after DPSI, recurrent endoleaks were observed in nine patients (50.0%), one type I endoleak due to graft migration, five type II endoleaks, and three EOUO. The occurrence of a re-endoleak during follow-up was significantly associated with dual-antiplatelet medication (0% in patients without re-endoleak vs 44.4% in patients with re-endoleak; P = .023) and with a nonsignificant trend for the use of aspirin alone (33.3% in patients without re-endoleak vs 80% in patients with re-endoleak; P = .094). Re-endoleak occurred in 33.3% of the patients without antiplatelet medication and in 100% of patients with dual-antiplatelet medication (P = .026). Thrombin was used as the sole embolic agent during the initial DPSI in all patients with dual-antiplatelet therapy. No other factor was significantly associated with re-endoleaks. Reintervention was deemed necessary in six patients within a median of 10 months (interquartile range, 4-16 months) after DPSI, including six additional DPSI treatments in four patients with type II re-endoleaks, cuff placements in one type I endoleak, and endograft relining in one EOUO. CONCLUSIONS This initial experience suggests that DPSI is feasible as a technique for endoleak treatment after EVAR. However, complications and endoleak recurrence remain a concern. The role of antiplatelet therapy and different embolic agents on long-term embolization success needs to be studied in more detail.

Motion characterization of aortic wall and intimal flap by ECG-gated CT in patients with chronic B-dissection

RATIONALE AND OBJECTIVES To evaluate whether dynamic computed tomography (CT)-imaging can provide functional vessel information in patients with chronic aortic dissection type Stanford-B (ADB). MATERIALS AND METHODS In 32 patients, ECG-gated CT-angiography images were obtained. Cross-sectional area change and wall distensibility were investigated by semiautomatic vessel area segmentation at the end of aortic arch. Significance of distensibility differences was tested with regard to the aortic diameter, and the oscillation of the intimal flap was analyzed. RESULTS The aorta could be segmented successfully in all patients. These were separated into three subgroups: (A) 6 patients with an aortic diameter <4 cm and without a visible intimal flap, (B) 9 patients with an aortic diameter <4 cm, and (C) 17 individuals with an aortic diameter > or = 4 cm; (B) and (C) having a visible intimal flap. Differences in distensibility between the subgroups were not significant. Overall mean distensibility was D(tot)=(1.3+/-0.6) x 10(-5) Pa(-1). Analysis of intimal flap oscillation showed a pulsatile short axis diameter decrease of the true lumen of up to 29%. CONCLUSION Dynamic, ECG-gated CT-angiography can demonstrate pulsatile changes in aortic area and a highly variable motion of the intimal flap. Aortic distensibility appears independent of diameter or presence of a intimal flap. Follow-up studies may show correlation with possible complications.