Two-Stage Elephant Trunk approach for open management of distal aortic arch and descending aortic pathology in patients with Marfan syndrome

Clinical Experience with “Stand-Alone” Elephant Trunk Procedure for Descending Aortic Aneurysms

Background  Both open and endovascular treatments of descending thoracic aortic aneurysms require a secure proximal landing zone. This may be difficult to achieve when the dilatation extends proximally to the left subclavian level. Clamping above the aneurysm may be difficult. In the case of an endovascular approach, achieving a suitable landing zone may require extensive extra-anatomic debranching, which is not without complications and limitations.

Methods  We describe a modification of the traditional elephant trunk procedure that represents a “stand-alone” elephant trunk. Under deep hypothermic circulatory arrest, the aorta is transected between the left carotid and left subclavian arteries. A simple, noninverted elephant trunk is placed through the distal cut aorta. The two ends are sewn back together, incorporating the lip of the elephant trunk in the anastomosis. We review our experience in five patients who underwent this procedure.

Results  All 5 patients (4 males, 1 female) aged 41 to 68 (mean, 57 years) tolerated the Stage 1 stand-alone elephant trunk procedure well, without mortality, stroke, or bleeding. The Stage 2 descending aortic replacements were performed at a mean of 6.7 months after Stage 1. There was no Stage 2 mortality, stroke, or bleeding. One patient died 8 years later of cardiac cause, and the remaining are alive and well.

Conclusion  A stand-alone elephant trunk procedure is safe and straightforward and provides an excellent proximal foundation for subsequent open (or potentially endovascular) descending aortic replacement.

Step-by-step aortic clamping technique for safe retrieval of the elephant trunk

Staged repair of the aortic arch and downstream aorta using the elephant trunk technique is widely accepted for extensive aortic disease. However, elephant trunk retrieval is challenging in patients with unclampable descending aorta caused by extreme aneurysmal dilation or surrounding tissue adhesion. Here, we introduce a new elephant trunk retrieval technique using the step-by-step aortic clamping in descending aortic replacement of dissecting aortic aneurysm. This technique is a safe and feasible method of elephant trunk retrieval that consists of staged clamping and intraoperative ultrasound assessment of blood flow in the aorta.

Simple Retrieval Technique of the Elephant Trunk by Partial Aortic Clamping

The frozen elephant trunk technique for various thoracic aortic diseases is widely accepted to facilitate future downstream aortic surgery. However, in some cases, the descending aorta is unsuitable for cross-clamping due to progressive aneurysmal changes or dense adhesions to surrounding structures, and frozen elephant trunk retrieval becomes challenging. This paper presents a case of successful frozen elephant trunk retrieval by partial clamping of the descending aortic aneurysm without dissection of peri-aneurysmal adhesions, and subsequent encircling.

Interstage mortality in two-stage elephant trunk surgery

PURPOSE

Diffuse mega-aorta is challenging. Prior studies have raised concerns regarding the safety of the open two-stage elephant trunk (ET) approach for extensive thoracic aortic aneurysm (TAA), specifically in regard to interstage mortality. This study evaluates the safety of the two-stage ET approach for management of extensive TAA.

METHODS

Between 2003 and 2018, 152 patients underwent a Stage I ET procedure by a single surgeon (mean age 64.5 ± 14.8). Second stage ET procedure was planned in 60 patients (39.4%) and to-date has been performed in 54 patients (90%). (in the remaining patients, the ET was prophylactic for the long-term, with no plan for near-term utilization).

RESULTS

In-hospital mortality after the Stage I procedure was 3.3% (5/152). In patients planned for Stage II, the median interstage interval was 5 weeks (range: 0-14). Of the remaining six patients with planned, but uncompleted Stage II procedures, five patients expired from various causes in the interval period (interstage mortality of 8.3%). There were no cases of aortic rupture in the interstage interval. Stage II was completed in 58 patients (including four unplanned) with a 30-day mortality of 10.3% (6/58). Seven patients developed strokes after Stage II (12%), and three patients (5.1%) developed paraplegia.

CONCLUSIONS

The overall mortality, including Stage I, interstage interval, and Stage II was 18.6%. This substantial cumulative mortality for the open two-staged ET approach for the treatment of extensive TAA appears commensurate with the severity of the widespread aortic disease in this patient group. Fear of interstage rupture should not preclude the aggressive Two-Stage approach to the management of extensive TAA.

Thoracic aortic aneurysms in patients with heritable connective tissue disease

BACKGROUND

Patients with connective tissue diseases are at high lifetime risk of developing thoracic aortic aneurysms (TAAs) due to defects in extracellular matrix composition which compromise the structural integrity of the aortic wall. It is vital to identify and manage aneurysms early to prevent fatal complications such as dissection or rupture.

METHOD

This review synthesises information obtained from a thorough literature search regarding the pathophysiology of TAAs in those with heritable connective tissue diseases (HCTDs), the investigations for timely diagnosis and current operative strategies.

RESULTS

Major complications of open repair (OR) include pneumonia (32%), haemorrhage (31%) and tracheostomy (18%), with a minor risk of vocal cord paresis (9%). For thoracic endovascular aortic repair (TEVAR), high rates of endoleak were documented (38-66.6%). Reintervention rates for TEVAR are also high at 38-44%. Mortality rates were documented as 25% for open repair and vary from 14% to 44% for TEVAR.

CONCLUSION

OR remains the mainstay of surgical management. While TEVAR use is expanding, it remains the alternative choice due to concerns over endograft durability, limited long-term outcome data and the lack of high-quality evidence regarding its use in HCTD patients.

Risk factors of delayed awakening after aortic arch surgery under deep hypothermic circulatory arrest with selective antegrade cerebral perfusion

Background

To determine the risk factors of delayed awakening following aortic arch surgery under deep hypothermic circulatory arrest (DHCA) in combination with selective antegrade cerebral perfusion (SACP).

Methods

We retrospectively analyzed the clinical data of all patients who underwent aortic arch surgery under DHCA + SACP between September 2015 and September 2017 in our hospital. Delayed awakening was defined as recovery of consciousness later than 24 hours after the surgery. Risk factors of delayed awakening were evaluated using multivariate logistic regression analysis.

Results

A total of 168 subjects were included. In-hospital mortality of the overall sample was 19.05% (n=32). Delayed awakening occurred in 76 (45.23%) subjects. Subjects with delayed awakening had older age, hypertension, higher rate of emergency surgery and blood transfusion, and longer cardiopulmonary bypass (CPB) time and myocardial blocking time. Multivariate regression analysis showed emergency surgery (P=0.005) and CPB time >240 min (P<0.001) as risk factors for delayed awakening, even after adjusting potential confounders, including age, hypertension, aortic cross-clamp time and blood transfusion.

Conclusions

In patients undergoing aortic arch surgery under DHCA + SACP, emergency surgery and CPB time >240 min are risk factors for delayed awakening.