Frozen Elephant Trunk Procedure Research Articles

Aortic remodelling effect of the frozen elephant trunk technique on Stanford type A acute aortic dissection.

Total arch replacement using the frozen elephant trunk procedure is performed for true lumen expansion of the descending aorta in patients with type A acute aortic dissection. However, the remodelling effect of the frozen elephant trunk on the dissected descending aorta is unclear. We aimed to evaluate the effect of the frozen elephant trunk on postoperative descending aortic remodelling after surgery. Between December 2012 and January 2020, we retrospectively investigated 24 patients who underwent total arch replacement using the frozen elephant trunk for type A acute aortic dissection. Remodelling of the descending aorta was evaluated using computed tomography. The aortic remodelling effect, based on aortic true lumen ratio, was determined for (i) DeBakey type (type I versus type III retrograde); (ii) thoracic endovascular aneurysm repair reintervention status (reintervention versus no reintervention); and (iii) stent length of the frozen elephant trunk (60 vs 90 mm). Postoperative true lumen ratio significantly increased in the type I dissection group. The true lumen ratio in the no-reintervention group, which had many patients with the type I dissection, significantly increased after the frozen elephant trunk. Aortic remodelling due to the frozen elephant trunk can be expected after type I acute aortic dissections.

Predictors of early adverse events after the frozen elephant trunk procedure

The aim of this study was to identify predictors of adverse events after the frozen elephant trunk procedure in the early postoperative period. Between March 2012 and March 2020, a total of 273 patients were operated on for aortic pathology. A retrospective analysis aimed at identifying probable predictors was performed on 83 patients who underwent the FET procedure. Uni- and multivariate logistic regression was used to identify predictors of such adverse events as postoperative delirium, respiratory failure, acute kidney injury, and in-hospital mortality. According to the findings of the optimal multivariate regression model, separate reimplantation of the supra-aortic branches was a significant predictor of postoperative delirium (OR 10.41; 95% CI 1.1-35.45; p=0.05); significant risk factors for prolonged respiratory support were the duration of surgery (OR 1.02; 95% CI 1.01-1.03; p<0.001) and postoperative acute renal injury (OR 8.72; 95% CI 1.67-57.38; p=0.014). Independent risk factors for postoperative renal injury turned out to be the true lumen diameter of the descending aorta (OR 1.3; 95% CI 1.1-1.72; p=0.015) and chronic type A aortic dissection (OR 44.07; 95% CI 3.29-2354.8; p=0.014); statistically significant risk factors for in-hospital mortality were multiple organ dysfunction syndrome (OR 14.34; 95% CI 1.69-155.48; p=0.016) and coronary artery stenosis (OR 3.36; 95% CI 1.19-13.26; p=0.042). Separate reimplantation of the supra-aortic branches, duration of surgery, acute kidney injury, chronic aortic dissection, multiple organ dysfunction syndrome, true lumen diameter of the descending aorta, coronary atherosclerosis and haemoglobin level were statistically significant predictors of adverse events in the early postoperative period.

25 Years' Experience with Redo Operations in Cardiac Surgery-Third-Time Sternotomy Procedures.

Over the years, open heart surgery has become more complex, and especially reoperative surgery, more demanding. The risk of third-time or more sternotomy procedures is unclear. We reviewed our institutional experience of 25 years based on two generations of cardiac surgeons in a German university medical center to document frequency, outcome, and complications of the various types of open heart procedures. Overall, we included 104 patients with a mean age of 64 ± 13 years. The EuroSCORE II (European System for Cardiac Operative Risk Evaluation) calculated an average mortality risk of 15.7 ± 15.4%. Subgroup comparison of isolated coronary artery bypass grafting (CABG), aortic valve replacement, and mitral valve replacement procedures did not delineate significantly different risk profiles except for the incidence of acute myocardial infarction, which was present in every second patient (53.3%) scheduled for CABG surgery. The time interval to previous surgery was 4.7 ± 6.3 years on average. Most frequent surgical procedures were valve operations, which were accomplished in 72 patients (69.2%), whereas coronary bypass surgery was performed in 23 patients (22.1%) only. Combined procedures were performed in 27 patients. Complex aortic arch replacement with a frozen elephant trunk procedure was necessary in six patients. Overall, 30-day survival was 81.7%. In conclusion, third-time and more sternotomy procedures offer acceptable outcome and should therefore be considered in appropriate patients.

Efficacy of entry exclusion strategy for DeBakey type III retrograde Stanford type A acute aortic dissection.

Resection of a primary entry tear is essential for the treatment of Stanford type A acute aortic dissection (AAAD). In DeBakey type III retrograde AAAD (DBIII-RAAAD), resection of the primary entry tear in the descending aorta is sometimes difficult. The frozen elephant trunk technique and thoracic endovascular aortic repair (TEVAR) enable the closure of the primary entry in the descending aorta. The aim of this study was to investigate the efficacy of resection or closure of primary entry, i.e. entry exclusion, in patients with DeBakey type III retrograde-AAAD. The medical records of 654 patients with AAAD who underwent emergency surgery between January 2000 and March 2019 were retrospectively reviewed, and 80 eligible patients with DeBakey type III retrograde-AAAD were divided into the excluded (n = 50; age, 62 ± 12 years) and residual (n = 30; age, 66 ± 14 years) groups according to postoperative computed tomography angiographic data of the false lumen around the primary entry. The excluded group was defined as having a postoperative false lumen at the level of the elephant trunk or thrombosis of the endograft including primary entry. Patients with early false lumen enhancement around the elephant trunk or an unresected primary entry tear after isolated hemiarch replacement were included in the residual group. The early and long-term surgical outcomes were compared between the groups. The in-hospital mortality rate was 8% (6/80), with no significant difference observed between the excluded and the residual groups (10% and 7%, respectively; P > 0.99). Ninety-five percentage of the patients (20/21) achieved entry exclusion with stent grafts including the frozen elephant trunk procedure and TEVAR. Spinal cord ischaemia was not observed in either group. The cumulative overall survival at 5 years was comparable between the 2 groups (76% and 81% in the excluded and residual groups, respectively; P = 0.93). The 5-year freedom from distal aortic reoperation rate was significantly higher in the excluded group (97%) than in the residual group (97% vs 66%; P = 0.008). Not only resection but also closure using the entry exclusion approach for DeBakey type III retrograde-AAAD utilizing new technologies including the frozen elephant trunk technique and TEVAR might mitigate dissection-related reoperations.

The frozen elephant trunk technique in an emergency: THORAFLEX French National Registry offers new insights.

Our goal was to study the immediate outcome after an emergency frozen elephant trunk procedure with a Thoraflex™ Hybrid prosthesis (THP) in patients included in the EPI-Flex national registry and operated on in 21 French centres. All patients operated on in France between April 2016 and April 2019 for acute aortic syndromes and who had an frozen elephant trunk procedure with a THP were included in the study. The main end point was in-hospital mortality. The secondary end point was neuromorbidity, including paraplegia. The evolution of the main end point was monitored using a variable life-adjusted display graph with cumulative sum derivatives in order to stop inclusions in case the observed mortality became out of range compared to an expected mortality between 15% and 20%. Enrolment ended on the scheduled date and included 109 patients. Most cases (54%) were performed at 3 centres, where more than 10 THP each were implanted (10-26). The observed mortality in the large-volume centres (22%) was comparable to that observed in the low-volume centres (20%). The individually risk-adjusted cumulative sum revealed that observed in-hospital mortality was statistically in line with that predicted by the log EuroSCORE. Analysis of the secondary end point revealed 8% cases of paraplegia, all of which appeared after treatment of the thoracic type A aortic dissection. In France, THP for emergency frozen elephant trunk surgery outside high-volume centres did not result in excessive in-hospital deaths. However, a word of caution must be expressed regarding the prevention of medullar ischaemia even in emergency aortic surgery.

Cardiopulmonary bypass duration is an independent predictor of adverse outcome in surgical repair for acute type A aortic dissection.

ObjectiveThis study aimed to investigate the relationship between the duration of cardiopulmonary bypass (CPB) and stroke or early death in patients with acute type A aortic dissection (ATAAD) receiving total aortic arch replacement with the frozen elephant trunk procedure (TAR with FET).MethodsA retrospective cohort study of 258 consecutive patients was conducted at Beijing Anzhen Hospital from December 2014 to June 2016. Patients who received TAR with FET for ATAAD were included. An adverse outcome (AO) was defined as 30-day mortality or stroke. Additionally, an AO was compared using propensity score matching.ResultsThe incidence of AO was 13.6% (n = 35). The 30-day mortality rate was 10.8% and the stroke rate was 9.3%. Patients were aged 47.9 ± 10.6 years old. The duration of CPB was an independent predictor of occurrence of AO after adjusting for confounding factors by multivariable logistic regression analysis (odds ratio 1.101, 95% confidence interval 1.003–1.208). In matched analysis, CPB duration remained a risk factor of AO.ConclusionsThe duration of CPB is an independent predictor of AO in surgical repair for ATAAD. The underlying mechanisms of this association are important for developing improved prevention strategies.

Acute retrograde type A intramural hematoma during severe acute respiratory syndrome coronavirus 2 pandemic

Acute intramural hematomas (IMHs) occur in ∼6% of patients with acute dissections (ADs) and mostly affect the descending aorta.1Harris K.M. Braverman A.C. Eagle K.A. Woznicki E.M. Reed E.P. Myrmel T. et al.Acute aortic intramural hematoma: an analysis from the International Registry of Acute Aortic Dissection.Circulation. 2012; 126: S91-S96Crossref PubMed Scopus (147) Google Scholar Type A IMHs involve the ascending aorta and type B IMHs do not involve the ascending aorta. Retrograde type A IMHs (retro-TAIMHs) originate in the descending aorta and extend into the arch or ascending aorta. TAIMHs with distal AD carry an in-hospital mortality risk of 12% to 26%.1Harris K.M. Braverman A.C. Eagle K.A. Woznicki E.M. Reed E.P. Myrmel T. et al.Acute aortic intramural hematoma: an analysis from the International Registry of Acute Aortic Dissection.Circulation. 2012; 126: S91-S96Crossref PubMed Scopus (147) Google Scholar,2Tolenaar J.L. Harris K.M. Upchurch Jr., G.R. Evangelista A. Moll F.L. Di Eusnio M. et al.The differences and similarities between intramural hematoma of the descending aorta and acute type B dissection.J Vasc Surg. 2013; 58: 1498-1504Abstract Full Text Full Text PDF PubMed Scopus (44) Google Scholar We report the case of an 85-year-old woman with acute retro-TAIMH and distal AD. The patient provided consent for the report of her case. She was admitted to the emergency room with acute onset dyspnea and chest pain but no evidence of malperfusion. Emergency computed tomography angiography identified a retro-TAIMH with AD and a proximal entry tear above the celiac axis (A/Cover). The patient was hemodynamically stable. She was treated with hypotensive and analgesic therapy and hospitalized for intensive monitoring. Follow-up computed tomography angiography was performed at 24 hours (B) and 7 days (C) showing progressive to complete thrombosis of the entry tear, with a reduction in the aortic diameter, the most important predictor of IMH regression and positive outcomes.3Evangelista A. Dominguez R. Sebastia C. Salas A. Permanyer-Miralda G. Avegliano G. et al.Prognostic value of clinical and morphologic findings in short-term evolution of aortic intramural haematoma: therapeutic implications.Eur Heart J. 2004; 25: 81-87Crossref PubMed Scopus (100) Google Scholar Complete symptom regression occurred. The event was observed during the peak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in Lombardy, Italy. The patient had tested positive for SARS-CoV-2 at 5 days after symptom onset, with progressive dyspnea and worsening findings on a chest radiograph (D). She died of pulmonary complications at 19 days postoperatively. Hybrid treatment with ascending aortic replacement and distal thoracic aortic endovascular repair (TEVAR) or using the frozen elephant trunk procedure is the most appropriate treatment for acute retro-TAIMH. TEVAR is a valid alternative only for patients with prohibitive surgical risk, although the landing zones could be unsuitable and the risk of neurologic and cardiac complications can be high.4Nauta F. De Beaufort H. Mussa F.F. De Vincentiis C. Omura A. Matsuda H. et al.Management of retrograde type A IMH with acute arch tear/type B dissection.Ann Cardiothorac Surg. 2019; 8: 531-539Crossref PubMed Scopus (7) Google Scholar Medical treatment appears to be appropriate for asymptomatic patients, those with noncomplicated retro-TAIMHs, and patients with high open surgical and TEVAR risks.4Nauta F. De Beaufort H. Mussa F.F. De Vincentiis C. Omura A. Matsuda H. et al.Management of retrograde type A IMH with acute arch tear/type B dissection.Ann Cardiothorac Surg. 2019; 8: 531-539Crossref PubMed Scopus (7) Google Scholar Considering both the absence of end-organ malperfusion and the advanced age of our patient, we chose medical treatment, which can reduce mortality by 67% to 95%.5Ince H. Nienaber C.A. Diagnosis and management of patients with aortic dissection.Heart. 2007; 93: 266-270Crossref PubMed Scopus (60) Google Scholar This choice proved effective with symptom recovery and clinical stability of the present patient, until the deadly overlap of SARS-CoV-2. Toward a unified pathophysiology in COVID-19 acute aortopathiesJournal of Vascular SurgeryVol. 74Issue 5PreviewThe interesting article by Katsarou et al1 about aortic intramural hematoma complicating a severe acute respiratory disease coronavirus 2 (SARS-CoV-2) infection is compelling, and its pathophysiology needs to be elucidated further. Full-Text PDF

The frozen elephant trunk technique for aortic dissection is safe after previous aortic repair.

The goal of this study was to evaluate outcomes of aortic arch replacement using the frozen elephant trunk (FET) technique after previous proximal and/or distal open or endovascular thoracic aortic repair. Sixty-three patients [median age: 63 (55-74) years; 65% men] were operated on for acute or chronic aortic dissection after previous proximal and/or distal open or endovascular thoracic aortic repair. Intraoperative details, clinical outcome and follow-up results were evaluated. The median time between the index and the FET procedure was 81 (40-113) months. Fifty-eight (92%) patients had already undergone proximal aortic surgery; supracoronary ascending aortic replacement was the most frequent index procedure [n = 25 (40%)]. Distal aortic interventions had been done in 8 (13%) patients including endovascular thoracic aortic repair in 6 patients (10%). In-hospital mortality was 3% (n = 2). Postoperative strokes occurred in 5 patients (8%); of those, 1 stroke was dissection-related (2%). Subsequent aortic reinterventions after the FET procedure had to be done in 33% (n = 21). Outcomes of aortic arch replacement using the FET technique after previous proximal and/or distal open or endovascular thoracic aortic repair are associated with low mortality and morbidity. Still, postoperative stroke remains an issue. After the successful accomplishments, the approach serves as an ideal platform for the secondary surgical or endovascular downstream aortic procedures, which are frequently needed.

Single-center experience with the frozen elephant trunk procedure in 111 patients with complex aortic disease.

BackgroundThe frozen elephant trunk (FET) technique is increasingly used for the treatment of acute and chronic aortic arch disease. This study reports our single center experience with the FET technique in patients with complex aortic disease.MethodsBetween 2009 and 2019, 111 consecutive patients underwent aortic arch surgery in our institution using the FET technique for acute type A dissection (AAD group; n=75) or non-acute type A dissection (non-AAD group; n=36; 10 patients with chronic type A dissection; 26 patients with aneurysm), respectively. Relevant perioperative data, including 30-day mortality and neurological complications, were retrospectively obtained from our electronic patient’s records, including follow-up (FU) data of outpatient clinical visits and computed tomography (CT).ResultsThirty-day mortality in the entire FET cohort was 16.2% (AAD 18.7% vs. non-AAD 11.1%; n=0.414). Severe brain injury was the leading cause of death in AAD patients (12.0% vs. 0% non-AAD; P=0.030). Overall permanent stroke and spinal cord injury was 12.6% and 3.6%. Four patients in the AAD group developed paraplegia and permanent stroke rate was significantly higher in AAD compared to non-AAD patients (17.3% vs. 2.8%; P=0.034). One, 3- and 5-year survival rates were 78.7%±4.0%, 72.2%±4.8%, and 64.3%±6.8% for the total cohort; survival at 1-, 3- and 5-year was 76.7%±5.0%, 71.0%±6.1%, and 64.5%±8.3% for the AAD cohort compared to 83.1%±6.3%, 75.0%±7.9% and 66.7% for non-AAD patients (P=0.579), respectively.ConclusionsOur single-center experience confirms good early and mid-term survival after the FET procedure in patients presenting with AAD, CAD and aneurysm. Future efforts should focus on reduction of severe neurological complication.

The Frozen Elephant Trunk Technique for the Treatment of Type B and Type Non-A Non-B Aortic Dissection

To evaluate outcomes of patients with acute complicated or chronic Type B or non-A non-B aortic dissection who underwent the frozen elephant trunk (FET) technique. Between April 2013 and July 2019, 41 patients presenting with acute complicated (n=29) or chronic (n=12) descending thoracic aortic dissection were treated by the FET technique, which was the treatment of choice when supra-aortic vessel transposition would not suffice to create a satisfactory proximal landing zone for endovascular aortic repair, when a concomitant ascending or arch aneurysm was present, or in patients with connective tissue diseases. One patient (2%) died intra-operatively secondary to an aortic rupture in dwnstream aortic segments. No post-operative deaths occurred. Four patients (10%) suffered a non-disabling posto-operative stroke and were discharged with no clinical symptoms (modified Rankin Scale [mRS] 0, n=1), no significant disability (mRS 1, n=2), or with slight disability (mRS 2, n=1). No spinal cord ischaemia was observed. The primary entry tear was either surgically resected or excluded from circulation in all patients. During follow up, one patient (2%) died after two years (not aorta related) and 16 patients (39%) underwent an aortic re-intervention after 7.7 [interquartile range 0.7, 15.8] months (endovascular aortic repair: n=14; open thoraco-abdominal aortic replacement: n=1, hybrid approach: n=1). The FET technique is an effective treatment option for acute complicated and chronic Type B or non-A non-B aortic dissection in patients in whom primary endovascular aortic repair is non-feasible. While the post-operative outcome is acceptable with a relatively low incidence of non-disabling strokes, this study also underlines the considerable need for aortic re-interventions. Continuous follow up of all patients undergoing the FET procedure is essential.

Rapidly Progressed Distal Arch Aneurysm with Distal Open Stent Graft-Induced New Entry Caused by "Spring-Back" Force.

The J Graft Open Stent Graft (JOSG) is used for the frozen elephant trunk procedure in Japan. We report a 70-year-old male who developed a rapidly progressing distal arch aneurysm caused by a distal stent graft-induced new entry (DSINE) 7 months after the procedure. The JOSG was originally implanted at the curved part of the distal arch. It created its initial DSINE on the greater curve and rapidly “sprang” back in 2 months. Urgent thoracic endovascular aortic repair fixed this serious complication. We should remember such rapid progression of DSINE by JOSG and treat its initial sign earlier.

Suturing Fenestration of the Left Subclavian Artery Orifice in Frozen Elephant Trunk Procedure.

The frozen elephant trunk (FET) procedure enables easier replacement of the entire aortic arch because it does not require reaching the distal part of the left subclavian artery (LSCA). However, it requires additional management for reconstruction of the LSCA, which is associated with bleeding events. However, the fenestrated FET technique confers a risk of endoleakage from the fenestration site. We report our unique novel technique in which the proximal side of the hybrid stent graft is cut into V-shape around the subclavian artery and sutured continuously around the orifice of the subclavian artery during aortic stump fixation.

Single-Stage Treatment of Extensive Aortic Pathology Using the Frozen Elephant Trunk Procedure.

Extensive pathology involving the aortic arch and descending aorta traditionally has been treated with two open procedures. We report our institutional experience with a single stage frozen elephant trunk procedure for treatment of extensive aortic pathology. Between June 2018 and October 2019, nine patients (eight males, 89%, mean age 61 ± 6 years) with extensive aortic pathology were operated using the frozen elephant trunk procedure. Five (56%) patients underwent primary operation for chronic arch and proximal descending aneurysm in two (22%) patients, chronic type B aortic dissection in two (22%) patients and penetrating aortic ulcer in one (11%) patient. The other four (44%) patients received reoperative surgery for chronic post-dissection aneurysms. For organ protection during the aortic arch procedure, we used selective antegrade cerebral perfusion and mild systemic hypothermia at 28°C. Early mortality was not observed. A single (11%) patient developed focal stroke. Unilateral vocal cord palsy was present in two (22%) patients. Spinal cord injury was not observed. Reexploration for bleeding was required in two (22%) patients. Prolonged ventilation, liver and kidney failure as well as cardiac morbidity were not observed. Two patients (22%) with anticipated Endoleak type Ib received TEVAR extension at follow up. Mid-term mortality was observed in two (22%) patients, due to pneumonia. The frozen elephant trunk procedure can be used for a single-stage treatment of patients with extensive aortic pathology, due to chronic degenerative aneurysms or post-dissection aneurysms involving the aortic arch and the descending aorta, with acceptable mortality and morbidity.

Repair of residual aortic dissections with frozen elephant trunk technique

In this study, we present our mid-term results of reoperation with the frozen elephant trunk procedure due to patent false lumen-related complications in patients previously undergoing supracoronary aortic repair for acute type A aortic dissection. Between January 2013 and September 2018, a total of 23 patients (17 males, 6 females; mean age 51.5±9.7 years; range, 30 to 67 years) who underwent ascending aortic replacement due to type A aortic dissection and, later, frozen elephant trunk procedure for residual distal dissection were included. For diagnostic purposes and follow-up, computed tomography angiography was performed in all patients, and both re-entry and aortic diameters were evaluated. Echocardiography was used to evaluate cardiac function and valve pathologies. The Ishimaru zone 0 (n=11, 47.8%), Ishimaru zone 1 (n=1, 4.3%), Ishimaru zone 2 (n=4, 17.4%), and Ishimaru zone 3 (n=7, 30.4%) were used for frozen elephant trunk stent graft fixation. The mean duration of cardiopulmonary bypass and antegrade selective cerebral perfusion was 223.9±71.2 min and 88.9±60.3 min, respectively. In-hospital mortality was 13%, while there was one (4.3%) aortic-related death and four (17.4%) re-interventions during follow-up. Early repair should be considered in the presence of persistent dissections due to alarmingly high mortality rates of reoperations. Reoperation with the frozen elephant trunk procedure has acceptable results and the decision of the procedure to be performed should be based on preoperative risk factors of the patient.

Frozen elephant trunk usage in acute aortic dissection.

This review discusses the clinical applications of the frozen elephant trunk procedure for patients with acute aortic dissection. Sub-analysis of the multicenter Japanese Frozenix study, J-ORCHESTRA, are presented, and recent reports of frozen elephant trunk usage for acute aortic dissection are discussed.

Long-term outcomes of the frozen elephant trunk procedure: a systematic review.

The frozen elephant trunk (FET) procedure remains an increasingly popular approach to address complex multi-segmental aortic pathologies, owing to their ability to promote false lumen thrombosis and reduce the need for second-stage operations. While the short-term outcomes of such procedures have been shown to be acceptable, much less is known regarding long-term outcomes. This systematic review evaluates long-term outcomes of the FET procedure. Studies with at least 12 months follow-up data on FETs were identified in four electronic databases. All studies were reviewed by two independent researchers and relevant data extracted. Long-term outcomes, including overall survival, freedom from reintervention, and freedom from aortic events, were evaluated using patient data recreated from digitized Kaplan-Meier curves. Thirty-seven studies with 4,178 patients were identified. The majority of the studies focused solely on acute dissections. Average follow-up was 3.2 years. Overall survival at 1-, 3-, and 5-year was 89.6%, 85.2%, and 82.0%, respectively. Freedom from reintervention at the same timepoints were 93.9%, 89.3%, and 86.8%, respectively. Mortality, permanent neurological deficit and spinal cord injury were 10.2%, 7.7%, and 6.5%, respectively. Survival after the FET procedure is favorable, though ongoing close serial monitoring is essential to assess for the need for further reintervention. Larger multi-institutional registries are required to provide more robust evidence to better elucidate the patient cohort that would most benefit from the FET.

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

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. 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. 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. 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.

Distal Stent Graft–Induced New Entries After the Frozen Elephant Trunk Procedure

This study sought to evaluate the incidence of and identify risk factors for distal stent graft-induced new entries (dSINEs) after the frozen elephant trunk (FET) procedure. Patient characteristics and radiographic and follow-up data on 126 patients treated for aortic dissections with the Thoraflex (Vascutek Ltd, Inchinnan, United Kingdom) FET device in 2 centers between November 2013 and December 2018 were evaluated. Stress-strain behavior and load-displacement curves ofthe Thoraflex and the E-Vita Open (Jotec Inc, Hechingen, Germany) FET prosthesis were evaluated by applying axial load to the most distal ring of the prostheses. dSINEs were diagnosed in 16 patients (13%). There was no difference in the underlying disease, aortic features, or FET stent graft dimension between patients with and without dSINEs. No predictors for dSINE occurrence in patients treated with the Thoraflex device were identified. The risk for dSINE development was 14% (95% confidence interval [CI], 0% to 22%), 16% (95% CI, 0% to 24%), and 25% (95% CI, 0% to 45%) after 12, 24, and 36 months, respectively. When prostheses were loaded axially to 2-mm maximal displacement, the Thoraflex prosthesis exhibited strongly nonlinear behavior with maximal stiffness for minimal displacements, whereas the E-Vita prosthesis showed nearly constant stiffness. In addition, the Thoraflex prosthesis showed an increase in stiffness when confined. dSINEs may develop at any time after the FET procedure, and the risk for dSINE development is high. No clinical or patient-specific risk factors were identified in this study. The design of the Thoraflex graft with a stiff distal ring may be a potential reason for the occurrence of dSINEs.

Early Results of a Novel Single-Stage Hybrid Aortic Arch Replacement Technique to Reduce Bypass and Circulatory Arrest Duration.

Hybrid repair procedures of the aortic arch have been utilized to reduce surgical risks and apply this therapy to patients who would not traditionally be candidates for open surgical repair. We present a variation on the frozen elephant trunk technique to further reduce cardiopulmonary bypass and circulatory arrest duration. After initiation of cardiopulmonary bypass and during systemic cooling, a wire is advanced from the femoral artery into the aortic arch. In the case of aortic dissection, intravascular ultrasound is used to confirm true lumen placement. Under circulatory arrest, the proximal aortic arch is resected and the wire externalized. Antegrade deployment of a stent graft is performed into the aortic arch and proximal descending aorta. The ascending aortic graft is sewn to the cut end of the aorta, incorporating the stent graft. The graft is cannulated and cardiopulmonary bypass reinitiated. The remainder of the arch replacement is performed during re-warming. Twenty two patients underwent this novel hybrid arch replacement procedure for aortic pseudoaneurysm, aortic dissection, or aneurysm. In comparison to the frozen elephant trunk procedure, where a dacron graft is inserted into the descending aorta, and later fixed with an endograft, this technique allows for immediate distal fixation. In the case of aortic dissection, there is immediate expansion of the true lumen with distal seal, potentially obviating the need for additional procedures. Mean duration of follow up is 12 months (range 1 - 14 months). The mean duration of cardiopulmonary bypass was 109.32 ±3.14 minutes. The mean duration of circulatory arrest was 18.00 ±1.33 minutes at a mean temperature of 23.64 ±0.58 degrees Celsius. There were no mortalities, no permanent disabling strokes, and no renal failure (requiring dialysis). This novel hybrid technique for aortic arch replacement is safe, significantly reduces cardiopulmonary bypass and circulatory arrest times, and is performed readily without need for fluoroscopy. In patients with thoracoabdominal aneurysms, the stent graft can be used as an elephant trunk for further thoracoabdominal aneurysm repair or branched thoracic endovascular aortic repair procedures.

Impact of Modified Frozen Elephant Trunk Procedure on Downstream Aorta Remodeling in Acute Aortic Dissection: CT Scan Follow-Up.

The aim was to evaluate the impact of a modified frozen elephant trunk procedure (mFET) on remodeling of the downstream aorta following acute aortic dissections. Over a period of 8years, 205 patients (mean age 62.6 ± 12.6 years) underwent a mFET (n = 69, 33.7%) or isolated ascending aorta replacement (n = 136, 66.3%) (iAoA). Aortic diameter was assessed at the aortic arch (AoA), at the mid of the thoracic aorta (mThA), at the thoracoabdominal transition (ThAbd) and at the celiac trunk level (AbdA). Mean follow-up was 3.3 ± 2.6years. In-hospital mortality was 14% (n = 28), 7% in mFET and 17% in the iAoA group (p = 0.08). At the end of the follow-up, overall survival was 84% (95% CI 70-92%) and 75% (65-82%) and freedom from aorta-related reoperation was 100% and 95% (88-98%) for mFET and iAoA, respectively. At iAoA, the average difference in diameter change per year between mFET and iAoA was for total lumen 0mm (- 0.95 to 0.94mm, p = 0.99), and for true lumen, it was 1.23mm (- 0.09 to 2.55mm) per year, p = 0.067. False lumen demonstrated a decrease in diameter in mFET as compared to iAoA by - 1.43mm (- 2.75 to - 0.11mm), p = 0.034. In mFET, at the aortic arch level the total lumen diameter decreased from 30.7 ± 4.8mm to 30.1 ± 2.5mm (Δr + 2.90 ± 3.64mm) and in iAoA it increased from 31.8 ± 4.9 to 34.6 ± 5.9mm (Δr + 2.88 ± 4.18mm). The mFET procedure provides satisfactory clinical outcome at short term and mid-term and has a positive impact on aorta remodeling, especially at the level of the aortic arch.