Frozen Elephant Trunk Group Research Articles

Mild Systemic Hypothermic Circulatory Arrest Using a Frozen Elephant Trunk Graft with Endo-Balloon Occlusion for Total Arch Replacement.

Stroke and paraplegia are serious complications of total aortic arch replacement (TAR). Hypothermic circulatory arrest and cerebral perfusion reduce the risk of neurologic complications, but longer circulatory arrest time remains a risk factor for such complications. We utilized a frozen elephant trunk (FET) with endo-balloon occlusion under mild systemic hypothermia, which allowed us to shorten circulatory arrest time. Between April 2007 and May 2020, 72 patients underwent elective TAR using antegrade cerebral perfusion (ACP). They were divided into 2 groups. 64 patients received conventional TAR with moderate systemic hypothermic (bladder temperature, 25-28°C) circulatory arrest (group C). We used a FET with endo-balloon occlusion and retrograde perfusion through the femoral artery for the newest 8 patients who had mild hypothermic (bladder temperature of 30°C) circulatory arrest (group B). The mean operation time (257.5 ± 42.1 versus 327.8 ± 84.9 min, P = .023), CPB time (144.4 ± 28.1 versus 178.2 ± 26.4 min, P = .003), cardiac arrest time (75.5 ± 21.2 versus 95.7 ± 56.4 min, P < .001), SCP time (100.8 ± 25.5 versus 124 ± 23.2 min, P < .001), lower body circulation arrest time (17.2 ± 4.2 versus 62.5 ± 19.3 min, P < .001) were significantly shorter in the endo-balloon occlusion group. There were no perioperative neurological and renal complications or mortality in FET group. The new technique enabled a decrease in mechanical ventilation time (8.6 ± 1.4 versus 13.9 ± 5.7 min, P = .015) and hospital length of stay (9.7 ± 1.8 versus 18.3 ± 4.6 min, P = .005). FET using an endo-balloon occlusion with mild hypothermia is a safe and an effective approach in TAR.

Early and long-term results of total arch replacement with the frozen elephant trunk technique for acute type A aortic dissection.

We evaluated the operative and long-term outcomes of the frozen elephant trunk (FET) technique for acute type A aortic dissection. This study evaluated 426 consecutive patients who underwent aortic repair for acute type A aortic dissection from June 2007 to December 2018 at our centre. Of these, 139 patients underwent total arch replacement with FET (FET group), and 287 underwent other procedures (no FET group). Ninety-two patients in the FET group were matched to 92 patients in the no FET group by using propensity score matching analysis. Thirty-day mortality and neurological dysfunction were not significantly different between the FET and no FET groups (1.4% vs 2.4%, P = 0.50 and 5.0% vs 6.3%, P = 0.61, respectively). Long-term survival was better in the FET group than in the no FET group (P = 0.008). Freedom from distal thoracic reintervention was similar in the FET and no FET groups (P = 0.74). In the propensity-matched patients, freedom from aortic-related death was better in the FET group than in the no FET group (P = 0.044). Operative outcomes showed no significant difference between the 2 groups. FET contributes to better long-term survival in patients with acute type A aortic dissection.

Early and mid-term outcomes of total arch replacement with the frozen elephant trunk technique for type A acute aortic dissection.

The aim of this study was to evaluate the outcomes of the frozen elephant trunk (FET) technique, using the J Graft FROZENIX for Stanford type A acute aortic dissection, in comparison with the unfrozen elephant trunk technique. Between January 2010 and August 2018, we performed total arch replacement for Stanford type A acute aortic dissection in our hospital. Thirty patients were treated by the elephant trunk procedure (ET group), and 20 patients were treated by the FET procedure (FET group). To evaluate aortic remodelling, we measured the area of the aorta, the true lumen and the false lumen at 12 months of follow-up. Preoperative characteristics and operation time were not significantly different between the 2 groups. The quantity of blood transfused was much greater in the ET group than in the FET group. Resection or closure of the most proximal entry tear was obtained in 73.3% (22 out of 30 patients) in the ET group and 100% (20 out of 20 patients) in the FET group (P = 0.015). There was no case that had recurrent nerve palsy or paraplegia in the FET group. Stent graft-induced new entry occurred in 3 cases (15.8%) in the FET group. There were no significant differences between the 2 groups in aortic area, true lumen area or false lumen area. Total arch replacement with the FET technique in Stanford type A acute aortic dissection carries a risk of distinct complications; however, with thorough advance planning, it should be possible to safely institute this treatment. Further randomization, with a comparison of each technique, is required to provide clear conclusions whether the FET is useful for acute Stanford type A aortic dissection.

Distal aortic remodelling after the standard and the elongated frozen elephant trunk procedure.

The aim of this study was to evaluate abdominal aortic remodelling after the standard compared with the elongated frozen elephant trunk (FET) technique in patients with aortic dissection. Twenty-six patients underwent surgery and were randomized into 2 groups. Fifteen patients were treated with the standard FET technique. Eleven patients were treated with the advanced FET technique using an additional thoracic stent graft implanted down to the coeliac artery, within 30 days after the first stent graft implantation. Preoperative and postoperative and 5-year follow-up computed tomography aortic scans were obtained along the stent graft (A), between the distal edge of the graft and the coeliac trunk (B) and at the abdominal aorta (C). In the standard FET group, positive and stable aortic remodelling occurred in segments A (100%), B (87%) and C (87%). Negative remodelling was found in 2/15 (13%) patients; 1 patient had an endovascular reintervention. In the elongated FET group, positive and stable remodelling were observed in segments A (100%), B (100%) and C (90.9%). Negative remodelling occurred in 1/11 (9.1%) patients. No reintervention was required. Cumulative survival, freedom from negative remodelling and distal aortic reintervention in the standard FET group and the elongated FET group were 72 vs 100% (P = 0.29); 67.5 vs 80% (P = 0.58) and 75 vs 100% (P = 0.61), respectively. The standard FET technique is an adequate measure to induce false lumen thrombosis and improve abdominal aortic remodelling. The elongated FET technique seems to be superior to the standard FET procedure in terms of freedom from aortic remodelling and the distal reintervention rate.

Hybrid and frozen elephant trunk for total arch replacement in DeBakey type I dissection

ObjectiveThe study objective was to determine whether hybrid aortic repair yields superior outcomes compared with the conventional surgical approach for DeBakey type I aortic dissection. MethodsA retrospective analysis of patients with DeBakey type I dissection admitted to Fuwai Hospital between January 2010 and December 2016 showed that 815 patients (86.9%) underwent open total arch replacement with frozen elephant trunk (frozen elephant trunk group) and 122 (13.1%) underwent hybrid aortic arch repair without deep hypothermic circulatory arrest (hybrid group). We selected 109 pairs of patients for propensity score matching. Outcomes included early postoperative death, a composite of complications, dissected aorta remodeling, long-term survival, and freedom from reoperation. ResultsEarly mortality and complication rates were lower in the hybrid group, but the difference was not statistically significant (9.2% vs 17.4%, P = .073; 15.6% vs 25.7%, P = .066). The rates of postoperative renal insufficiency was significantly lower in the hybrid group than in the frozen elephant trunk group (22.9% vs 38.5%, P = .013); liver insufficiency and paraplegia were significantly lower in the hybrid group than in the frozen elephant trunk group (20.2% vs 33.9%, P = .022; 0% vs 6.4%, P = .014). After matched, the 1-year, 3-year, and 5-year survivals were 87.6%, 86.3%, and 82.2%, respectively, in the hybrid group and 80.7%, 76.5%, and 74.6% (P = .071), respectively, in the frozen elephant trunk group. ConclusionsHybrid aortic arch repair is a viable alternative treatment for patients with DeBakey type I aortic dissection, which improves outcomes and promotes remodeling of the dissected thoracic aorta.

Total aortic arch replacement using elephant trunk or frozen elephant trunk technique: a case-control matching study.

Surgical management of aortic arch diseases is one of the most challenging issues in cardiovascular surgery. The aim of this study was to compare the outcome after frozen elephant trunk (FET) with conventional elephant trunk (ET) technique. Out of a total of 551 patients after thoracic aortic surgery, we analyzed 70 consecutive patients, who underwent aortic arch replacement with ET or FET technique between 2001 and 2017 in our institution. The patients were case-control matched in regard to such variables as age, sex, presence of an acute aortic dissection and necessity for concomitant procedures. The analysis included 25 patient pairs. Among the 25 FET patients, eleven patients were female, the median age was 69, 15 (60%) patients had an aortic dissection and thirteen needed various concomitant procedures. In the second group, treated with conventional ET technique, 10 (40%) patients were female, the median age was 66 years, thirteen presented with an aortic dissection and 16 (64%) underwent concomitant procedures. These and other characteristics did not differ significantly between the groups. In-hospital mortality was statistically similar: 5 (20%) in the FET group vs. 8 (32%) for ET group (P=0.52). The incidence of stroke, acute renal failure and postoperative bleeding was comparable. The length of stay in the intensive care unit did not differ between the cohorts (P=0.258). Predictors of in-hospital mortality were length of the operation, bleeding postoperatively, and acute renal failure. The one-year survival rates were higher in the FET cohort compared to the conventional approach (60% vs. 38%), however without statistical significance. In regard to the short- and mid-term outcome, there were only slight differences between both techniques. In patients with extensive aneurysmal aortic disease, conventional ET and FET procedures seem to be associated with acceptable satisfactory mid-term outcome.

Aortic remodeling with frozen elephant trunk technique for Stanford type A aortic dissection using Japanese J-graft open stent graft

The frozen elephant trunk (FET) technique allows single-stage extended surgical repair of Stanford type A aortic dissection and has shown promotion of aortic remodeling by maintaining the true lumen flow and facilitating its expansion and by promoting false lumen thrombosis. However, few studies have compared the effectiveness of FET technique, in terms of the downstream aortic remodeling. Between 2005 and 2017, 50 patients underwent total arch replacement for Stanford type A aortic dissection, including that with (n = 22) and without FET technique (n = 28). We compared distal aortic remodeling in patients who underwent total arch replacement with (using a J-Graft open stent graft) or without the technique. The false lumen complete thrombosis rate and the ratio of true lumen area at three levels of the descending aorta were evaluated post operation. In FET group, the diameter and length of the stent graft were 29.0 ± 3.9 mm and 70.9 ± 17.4 mm, respectively. The in-hospital death with and without the FET technique was 0 and 3, respectively, with no late death in both groups. Eight patients (28.6%) only in the non-FET group required additional surgical treatment for downstream aorta. In the FET group, the ratio of true lumen area at the level of bronchial carina and false lumen complete thrombosis rate at the levels of bronchial carina and aortic valve were significantly higher than non-FET group. A more favorable remodeling in the descending aorta was observed in patients who underwent FET associated with a total arch replacement compared to those who underwent total arch replacement alone.

Acute Type I aortic dissection: a propensity-matched comparison of elephant trunk and arch debranching repairs.

Our goal was to compare the performance of the frozen elephant trunk (FET) and the hybrid aortic arch debranching procedures for acute Type I aortic dissection. From January 2013 to December 2015, 168 patients with Type I aortic disease underwent ascending aorta and total aortic arch replacement with FET implantation (the FET group, n = 132) or arch debranching with 1-stage aortic arch exclusion using an endovascular stent in a retrograde manner (the debranching group, n = 36). A propensity score-matched subgroup of 26 pairs was identified. Perioperative data and mid-term follow-up results were assessed. In the FET and the debranching groups, the 30-day mortality rates were 14.4% and 5.6% (P = 0.254) and the incidence of stroke was 5.3% and 5.6% (P > 0.999). Cardiopulmonary bypass time was significantly shortened, and the circulatory arrest was exempted in the debranching group. Cardiopulmonary bypass time was identified as a predictor for 30-day mortality (P = 0.027, odds ratio 1.01). Body mass index ≥ 25 kg/m2 was associated with multiorgan dysfunction syndrome (P = 0.016, odds ratio 3.51). Surgical modality did not significantly affect early outcomes. The 3-year survival rate was 76.1% (95% confidence interval, 63.0-81.9%) in the FET group and 82.5% (95% confidence interval, 65.2-91.8%) in the debranching group (P = 0.330). The hybrid aortic arch procedure without circulatory arrest can be safely performed on patients with acute Type I aortic dissection. Irrespective of cost-effectiveness, arch debranching was a promising alternative for patients who were unfit for the FET procedure.

Experience with the conventional and frozen elephant trunk techniques: a single-centre study

The treatment of patients with extensive thoracic aortic disease involving the arch and descending/thoracoabdominal aorta is often performed using an elephant trunk procedure. We retrospectively analysed our results comparing two different techniques: the conventional elephant trunk (cET) and the frozen elephant trunk (FET) operation. Between January 2003 and December 2011, 171 consecutive patients underwent total aortic arch replacement with either a cET (n = 125) or FET (n = 46) technique. The mean age was 64 ± 13 years and was significantly higher in the FET group (P < 0.01). Acute Type A aortic dissection was the indication for surgery in 53.6% of cET and 17.4% of FET patients, and degenerative or atherosclerotic aneurysm accounted for 33.6% of cET and 58.7% of FET patients. The remaining patients were operated on for chronic Type A or acute or chronic Type B dissections with arch involvement. In-hospital mortality was 21.6 vs 8.7% for cET and FET patients, respectively (P = 0.1). Logistic regression analysis revealed Type A aortic dissection (odds ratio (OR) 3.1, P = 0.01) as the only independent predictor of hospital mortality. Stroke occurred in 16 vs 13% of cET vs FET patients (P = 0.4). Type A aortic dissection was an independent predictor of stroke by multivariable analysis (OR 2.6, P = 0.03), and axillary arterial cannulation was protective against stroke (OR 0.4, P = 0.04). The occurrence of new-onset paraplegia was significantly higher in the FET group (21.7 vs 4.0%, P < 0.001), and aortic repair with the FET technique was an independent predictor for paraplegia (OR 6.6, P = 0.001). Among patients receiving FET, a body core temperature during circulatory arrest of ≥ 28 °C in combination with a prolonged circulatory arrest time of >40 min was an independent predictor for permanent spinal cord injury (OR 5.0, 95% CI 1.1-20, P = 0.038). The estimated 1-, 3- and 5-year survival were 70 ± 4, 70 ± 4 and 68 ± 4% (cET) and 4 ± 7 and 60 ± 9, 40 ± 1% (FET), with mean survival time 5.2 ± 0.3 vs 3.8 ± 0.5 years (cET vs FET, log-rank P = 0.9). The FET procedure for extensive thoracic aortic disease is associated with an acceptable mortality rate, but with a higher incidence of perioperative spinal cord injury than cET. Arch replacement with a cET technique should be strongly considered in patients with expected prolonged circulatory arrest times, particularly if operated on under mild or moderate hypothermia. Axillary cannulation is associated with superior neurological outcomes and Type A acute aortic dissection is a risk factor for mortality and poor neurological outcomes in this patient population.

Should the dissected aortic arch be replaced in acute type A dissection? The Mayo Clinic perspective.

Should the dissected aortic arch be replaced in acute type A dissection? The Mayo Clinic perspective.

Operative Strategy for Acute Type A Aortic Dissection: Ascending Aortic or Hemiarch Versus Total Arch Replacement With Frozen Elephant Trunk

This report compares long-term results with total arch replacement with frozen elephant trunk (FET) to ascending aortic or hemiarch replacement (AHR) for acute type A aortic dissection. The subjects were 120 consecutive patients, including 65 who received FET and 55 who had AHR for acute type A aortic dissection from 1997 to 2008. The late results after surgery were retrospectively compared between the FET and ARH groups. Three patients in the FET group died, and 2 patients in the AHR group died. In long-term follow-up (mean, 67 months), the survival rate after 5 years was 95.3% for the FET group and 69.0% for the AHR group (p = 0.03). The event rate for the thoracic aorta after 5 years showed a significant difference between the FET and AHR groups (95.7% versus 73.0%, p = 0.01). A false lumen at the proximal descending aorta was patent in 16 patients (29%) in the AHR group, but it was thrombosed in all in the FET group. In patients with acute type A aortic dissection, it is possible to perform extensive primary repair using the FET technique with relative safety. FET may reduce the necessity for further operations to manage a residual false lumen.