Mariano Cefarelli

Frozen elephant trunk surgery in acute aortic dissection

OBJECTIVES Acute aortic dissection is a catastrophic condition, for which emergency surgery is the mainstay of therapy. In approximately 70% of patients who survive surgery, a dissected distal aorta remains, posing a risk of late aneurysmal degeneration, rupture, and malperfusion, and secondary extensive interventions are often required. METHODS In order to improve the long-term prognosis, a more extensive intervention, the frozen elephant trunk (FET) procedure, has been introduced. This involves the simultaneous replacement of the aortic arch and antegrade stenting of the descending thoracic aorta (DTA). Although FET is assumed to produce total thoracic aortic remodeling by inducing both coverage of secondary entry tears located in the proximal DTA and obliteration of the false lumen at the proximal DTA, its role in patients with acute dissection remains controversial mostly because of its technical complexity and increased risk of paraplegia. RESULTS Data available in literature show that, after FET interventions, hospital death, stroke, and spinal cord injury occur in 10.0%, 4.8%, and 4.3% of patients with acute dissection, respectively. Available long-term data are sparse but suggest that aortic remodeling with partial or complete thrombosis of the persistent false lumen can be expected in approximately 90% of cases. CONCLUSIONS The FET technique is a promising approach in patients with acute dissection. Solid long-term data are warranted to validate the assumed short- and long-term benefits, but we believe that thoughtful patient selection criteria remain crucial.

Total Arch Replacement Versus More Conservative Management in Type A Acute Aortic Dissection.

BACKGROUND Surgical management of aortic arch in type A acute dissection (TAAD) is controversial. This study compared short-term and long-term outcomes of total arch replacement (TAR) interventions versus more conservative arch management (CAM). METHODS Between 1997 and 2012, 240 patients underwent TAAD surgery in our institution; 53 (22.1%) received TAR and 187 (77.9%) received CAM. Compared with CAM patients, those undergoing TAR were younger (59.1 vs 64.4 years, p = 0.004) and were less likely to present with cardiogenic shock (3.8 vs 14.4, p = 0.02). Distal site of intimal tear (arch or descending aorta) was predictive of TAR management (odds ratio [OR], 9.1; p < 0.001). RESULTS Hospital mortality was similar in the groups (24.1% vs 22.6%; p = 0.45), and no other significant differences were observed in terms of major postoperative complications. Age (OR, 1.047; p = 0.007) and cardiopulmonary bypass time (OR, 1.005 per minute; p = 0.05) emerged as independent predictors of hospital death. The TAR management did not affect hospital mortality (propensity score [PS] adjusted OR: 1.51, p = 0.36). On Kaplan-Meier analysis, 7-year survival (TAR, 52.1% ± 0.9% vs CAM, 57.2% ± 4.2%, log-rank p = 0.9) and freedom from aortic re-intervention (TAR, 71.6% ± 1.3% vs CAM, 85.4% ± 3.9%, log-rank p = 0.3) were similar. The PS-adjusted Cox regression showed no relationship between type of arch management and follow-up survival (hazard ratio [HR], 1.001; p = 0.8) or need for re-intervention (HR, 1.507; p = 0.4). CONCLUSIONS In our experience TAR and CAM were associated with similar hospital mortality and morbidity rates. Nevertheless, the more extensive arch interventions were not protective for long-term survival and freedom from aortic re-intervention. Thus, in TAAD patients TAR remains indicated by site of intimal tear and patient-specific factors.

Reoperative surgery on the thoracic aorta.

OBJECTIVE The objective of our study was to report our hospital and long-term results after reinterventions on the thoracic aorta. METHODS Between 1986 and 2011, 224 reoperations on the proximal thoracic aorta after previous aortic surgery were performed in our institution. The number of reinterventions quadrupled during the course of the study period. Mean patient age was 58.1 years, and 174 patients (77.7%) were male. An urgent/emergency operation was performed in 39 patients (17.4%). Indications for surgery included degenerative and chronic postdissection aneurysm (n = 166), false aneurysm (n = 31), active prosthetic infection (n = 16), acute dissection (n = 10), and other (n = 1). Surgical procedures involved the aortic root in 40.6% of patients, the ascending aorta in 9.4%, the aortic arch in 24.6%, and the entire proximal thoracic aorta in 25.4%. RESULTS Hospital mortality was 12.1%. On multivariate analysis, cardiopulmonary bypass time (odds ratio, 1.1023/minute; P < .001), and urgent/emergency status (odds ratio, 5.6; P < .001) emerged as independent predictors of hospital mortality. The follow-up was 98.7% complete. Estimated 1-, 5-, and 10-year survival rates were 84.4%, 72.5%, and 48.5%, respectively. Eighteen reinterventions were performed during follow-up-16 because of the progression of aortic disease at the proximal aorta (n = 2) and downstream aorta (n = 14). Freedom from reoperation at 1, 5, and 10 years was 95.6%, 90.2%, and 81.5%, respectively. CONCLUSIONS Reoperative aortic surgery was associated with satisfactory short- and long-term results, especially if carried out on an elective basis. The extent of the aortic replacement did not impact survival and was associated with a reduced need for reintervention. The progressive nature of aortic disease and the favorable results of elective primary aortic interventions suggest favoring aggressive aortic resections at initial surgery.

Antegrade stenting of the descending thoracic aorta during DeBakey type 1 acute aortic dissection repair

Several studies have shown that after DeBakey type 1 acute aortic dissection (DB1-AAD) surgery, 70% of the surviving patients still present with a dissected distal aorta that can eventually dilate, rupture, lead to distal malperfusion or require secondary extensive interventions. In order to minimize these complications, different surgeons have advocated total thoracic aorta remodelling procedures during primary aortic repair to promote false-lumen obliteration and distal thrombosis. Such management, which includes arch replacement and antegrade stenting of the dissected descending thoracic aorta (DTA), remains controversial due to its perceived increased operative mortality. Furthermore, the desired long-term benefits remain to be confirmed. The present article aimed to evaluate results of antegrade stenting of DTA during surgery for DB1-AAD, focusing on in-hospital mortality and morbidity, and long-term survival, occurrence of distal aortic remodelling and freedom from aortic reinterventions. Early results from the identified studies suggested that hybrid repair of DB1-AAD with antegrade DTA stenting was associated with satisfactory in-hospital mortality (10.0%) and stroke (4.8%) rates, while the risk of spinal cord injury appeared to be higher (4.3%) than that reported from historical controls. Furthermore, antegrade stenting of DTA was associated with promising rates of partial/complete thrombosis of the peristent DTA false lumen (88.9%), suggesting that aortic remodelling is highly probable with this approach. Evidence on long-term results after proximal acute dissection repair is still sparse, and mostly jeopardized by limited data beyond 5 years. Further investigations with longer term follow-up and with specifically designed protocols to assess long-term clinical outcomes (late aortic mortality and freedom from distal aortic reinterventions) of total thoracic aortic remodelling procedures vs more conservative management are warranted to reach more definitive conclusions.

Long-term outcomes after aortic arch surgery: results of a study involving 623 patients.

OBJECTIVES To assess early and long-term outcomes in a large cohort of patients undergoing open aortic arch surgery. METHODS From 1996 to 2012, 623 consecutive patients (mean age: 62.8 years) underwent aortic arch interventions in our institution. Of these, 208 (33.4%) presented with an acute aortic syndrome (AAS) and 415 (66.6%) with a chronic aortic pathology (CAP). During the study period, our surgical strategy involved extensive resections of the diseased aortic tissue at elective interventions, and a tear-oriented aortic replacement in patients with acute dissection. More extensive interventions were often performed in younger patients, and in those with connective tissue diseases and bicuspid aortic valves. A total arch replacement was frequently performed (53.3%). Antegrade selective cerebral perfusion was used in all cases. RESULTS Overall in-hospital mortality was 23.1% in patients with AAS and 11.1% in patients with a CAP; in the same groups, postoperative permanent neurological dysfunction (PND) occurred in 9.6 and 5.6%, respectively. The follow-up was 94.4% complete. For in-hospital survivors, 5- and 10-year survival (%) were 79.4 ± 2.1 and 60.9 ± 3.2, respectively, not influenced by the underlying aortic disease. Cox regression identified age (hazard ratio [HR]: 1.048; P < 0.001), preoperative renal failure (HR: 2.3; P = 0.003), diabetes (HR: 1.805; P = 0.005) and PND (HR: 2.4; P = 0.03) to be independent predictors for the follow-up mortality. Overall, 109 (59% endovascular) aortic reinterventions were performed: 18.3% were proximal and 81.7% distal to the aortic arch. Five- and 10-year freedom from aortic redo (%) were 82.8 ± 1.9 and 77.7 ± 2.6, respectively. Aortic dissection (HR: 1.7; P = 0.03) was the only independent predictor of reoperative surgery at the follow-up. CONCLUSIONS Aortic arch surgery was associated with satisfactory early and long-term outcomes. Survival was largely determined by patient comorbidities and postoperative PND. While the underlying aortic disease did not affect long-term mortality, chronic dissection was associated with increased need for aortic reinterventions.

Impact of Different Cannulation Strategies on In-Hospital Outcomes of Aortic Arch Surgery: A Propensity-Score Analysis

BACKGROUND The impact of different cannulation strategies on outcomes of aortic arch surgery remains controversial. This retrospective study sought to evaluate central cannulation (ascending aorta, right axillary, and innominate artery) compared with femoral artery cannulation for aortic arch surgery, and to identify among preoperative and intraoperative variables the independent predictors of death and permanent neurologic dysfunction (PND) in aortic arch surgery. METHODS All patients were operated through a median sternotomy using antegrade selective cerebral perfusion with moderate hypothermia as a method of brain protection. Treatment bias was addressed by use of propensity-score matching and multivariate regression analysis. Logistic regression models were used to identify the independent predictors of hospital mortality and PND. RESULTS Of the 473 patients undergoing aortic arch surgery, 273 (57.7%) underwent femoral cannulation (FC), and 200 (42.3%) underwent central cannulation (CC). The CC and FC cannulation were associated with similar risk of in-hospital death (absolute risk reduction [ARR]: 0.7%; p = 0.880) and PND (ARR:-2.6%, p = 0.361) in the overall cohort and after adjusting for propensity-based matching (ARR for hospital mortality: 2.2%, p = 0.589; ARR for PND: 3.4%, p = 0.271). Female gender (odds ratio [OR]:2.1, p = 0.030), type A acute dissection or intramural hematoma (OR: 2.2; p = 0.041), and CPB time (OR: 1.010/minute, p = 0.015) were independent predictors of in-hospital death. Female gender (OR: 2.4; p = 0.033), type A acute dissection or intramural hematoma (OR: 4.2; p = 0.005), and diabetes (OR: 6.6, p = 0.007) were independent predictors of PND. CONCLUSIONS During aortic arch surgery, CC and FC are associated with a similar risk of postoperative death and PND. Type A acute aortic dissection and cardiopulmonary bypass time remain strong risk factors for mortality and PND.

Surgical management of aortic root in type A acute aortic dissection: a propensity-score analysis

OBJECTIVES Surgical management of the aortic root in type A acute aortic dissection (TAAAD) is controversial. This study compares short- and long-term outcomes of root replacement (RR) versus conservative root management (CR). METHODS Between 1999 and 2014, 296 patients with TAAAD were treated in our department. The mean age was 63.7 years. Of the total, 69% were male. Ten patients (3%) presented with Marfan syndrome or bicuspid aortic valve. RR was performed in 119 (40%) patients, whereas CR in 177 (60%). Pre- and intraoperative data were stratified according to root management, and treatment bias was addressed by propensity-score (PS) analysis. Independent predictors of hospital and long-term mortality and proximal aortic reoperation were identified using multivariable logistic and Cox regression models. RESULTS Using PS analysis, we obtain two groups of 82 patients. The matched cohort hospital mortality rate was 21% in the CR group and 26% in the RR group (P = 0.45). The unadjusted comparison showed no statistical difference in early and long-term mortality between the groups. This result was confirmed after standard logistic regression and propensity-adjusted logistic regression. Freedom from proximal aortic reintervention was higher in the RR group (at 7 years RR: 96 ± 3% vs CR: 80 ± 6%, log-rank P = 0.02) and remained high in the matched cohort of patients (at 7 years RR: 98 ± 2 vs CR: 86 ± 6, log-rank P = 0.06). CONCLUSIONS Conservative and aggressive root management in acute aortic dissection provided similar results for early and late mortality. Nevertheless, a more extensive root intervention appeared to be protective against aortic reintervention.

Aortic Root Replacement With Biological Valved Conduits.

The execution of Bentall procedures using biological valved conduits is expanding owing to the increased incidence of aortic valve and root diseases in the aging population. To review the available data, a systematic search identified 29 studies with a total of 3,298 patients. Although evidence on short-term results suggested favorable outcomes after biological Bentall operations, data beyond 5 years are limited and highlight the urgent need for further investigations with longer follow-up.

The Bologna experience with the Thoraflex™ hybrid frozen elephant trunk device

BACKGROUND We present our initial experience with the frozen elephant trunk using a Thoraflex™ hybrid device for the treatment of the complex thoracic aorta lesions. MATERIALS & METHODS Between March 2013 and March 2014, ten patients underwent thoracic aorta surgery using the frozen elephant trunk approach with the Thoraflex hybrid device. Indications for surgery were: residual type A chronic dissection (eight patients), degenerative aneurysm (one patient) and type B chronic aortic dissection (one patient). Selective antegrade cerebral perfusion and moderate hypothermia were used in all cases. RESULTS In-hospital mortality was 0% and no patients presented with paraplegia, paraparesis or major neurological events. One patient experienced transient ischemic attack. Two patients underwent reoperation for bleeding. All postoperative angiography CT scans confirmed the desired results. CONCLUSION Our initial experience demonstrated excellent early results. The Thoraflex hybrid prosthesis with the four-branched arch graft increases the spectrum of techniques available for the surgeon in the treatment of complex diseases of the thoracic aorta.

Frozen elephant trunk surgery using the Vascutek Thora-flex hybrid prosthesis

The Vascutek Thoraflex hybrid graft (Vascutek, Scotland) is a novel commercially available 4-branched frozen elephant trunk (FET) graft used to treat patients with extensive diseases of the thoracic aorta (1). This hybrid prosthesis is composed of a distal endograft sealed to a proximal 4-branched gelweave graft with an incorporated sewing collar (Figure 1). Figure 1 The Vascutek Thora-flex hybrid prosthesis The text of this manuscript describes our FET technique with the Vascutek Thoraflex hybrid graft in detail (Video 1). Video 1 Frozen elephant trunk surgery using the Vascutek Thora-flex hybrid prosthesis Clinical vignette A 73-year-old man who had undergone a supra-coronary ascending aorta replacement for a DeBakey type 1 acute aortic dissection in a different Institution in 1997 was recently referred to our hospital for a residual chronic post-dissection aneurysm of the thoraco-abdominal aorta. Upon admission, the angio CT scan showed severe dilatation of the thoracic (48 mm) and abdominal (72 mm) aorta. The false lumen of the abdominal aorta was completely thrombosed; all the visceral vessels originated from the true lumen of the dissection with the exception of the left renal artery; large intimal tears were identified at the origin of the innominate artery and at the level of distal descending thoracic aorta. The native aortic root measured 33 mm (Figure 2). A trans-thoracic echocardiogram showed a competent tricuspid aortic valve and a normal left ventricular ejection fraction (62%). The preoperative coronary angiogram revealed severe 3-vessel coronary artery disease with critical stenoses of the left anterior descending, obtuse marginal and right coronary arteries. Figure 2 Angio CT image showing the residual DeBakey type 1 aortic dissection of the thoraco-abdominal aorta The patient was scheduled for a 3-staged hybrid treatment involving complete arch replacement with the FET and myocardial revascularization (stage 1), replacement of the abdominal aorta with visceral vessel de-branching (stage 2), and endovascular stenting of the remaining aortic segments from the FET to the abdominal aortic graft (stage 3). This video focuses on the stage-one procedure.