| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
J Thorac Cardiovasc Surg 2001;122:587-591
© 2001 The American Association for Thoracic Surgery
Surgery for Acquired Cardiovascular Disease (ACD) |
From the Department of Cardiovascular Surgery, University Hospital Berne, Berne, Switzerland.
Received for publication Aug 23, 2000. Revisions requested Dec 1, 2000; revisions received Feb 5, 2001. Accepted for publication March 23, 2001. Address for reprints: T. Carrel, MD, Department of Cardiovascular Surgery, University Hospital, CH-3010 Berne, Switzerland (E-mail: thierry.carrel{at}insel.ch).
Abstract
Background: The elephant trunk technique with a free-floating vascular prosthesis was originally developed to facilitate a subsequent operation on the downstream aorta. We present here our experience with further developments of this technique, which we call the reversed elephant trunk and bidirectional elephant trunk.
Methods: Between January 1, 1995, and December 31, 2000, 505 adult and adolescent patients underwent operations of the thoracic aorta. A reversed elephant trunk procedure in 13 patients and a bidirectional elephant trunk procedure in 4 patients was performed to facilitate either subsequent proximal or proximal and distal aortic replacement. Nine patients underwent subsequent aortic arch replacement with the reversed prosthetic portion after a mean interval of 8 ± 5.5 months, and 2 patients received distal extension by use of the distal portion of the free-floating graft.
Results: There was no hospital mortality (30 days) in this small group of patients, and no patient had aortic rupture, malperfusion caused by the technique itself, or thromboembolic complications during the waiting interval between the first and the second operations. Five patients are still being observed until the contiguous aortic size is large enough to require an operation, and one 74-year-old patient declined a second-stage operation.
Conclusion: The reversed and bidirectional elephant trunk techniques are interesting options that may be suitable for patients having complex abnormalities of the thoracic aorta and thoracoabdominal aorta when the proximal portion of the descending aorta has to be replaced before the aortic arch with or without the ascending aorta or the distal descending aorta with or without the thoracoabdominal aorta.
Aneurysms of the aortic arch and descending aorta may be limited to this portion of the aorta, but in a significant proportion of the patients, they may involve several parts of the thoracic aorta. The earliest experience with staged repair of the aorta from the coronary ostia to below the middle portion of the descending aorta was fraught with problems of bleeding and lack of adequate cerebral protection. The elephant trunk technique with a free-floating vascular prosthesis was originally described by Borst and colleagues
1,2 to facilitate subsequent operation on the downstream aorta. The elephant trunk can be placed within the proximal descending aorta as an extension of aortic arch replacement (ie, the proximal elephant trunk technique) or more distally as an extension of a descending thoracic aortic graft (ie, the distal elephant trunk technique). Since the initial report, several modifications have been reported by different groups. 3-7
In 1996, our group presented further refinements of this technique, which we called the reversed and bidirectional options, at the Fifth Aortic Surgery Meeting in New York, and the procedure was used in 3 patients. Since this initial report, we have performed this technique in 17 patients with extensive aortic disease, especially when the proximal descending aorta had to be replaced first.
Patients and methods
Between January 1, 1995, and December 12, 2000, 505 adult and adolescent patients underwent operations on the thoracic aorta. A reversed elephant trunk procedure in 13 patients and a bidirectional elephant trunk procedure in 4 patients were performed to facilitate either subsequent proximal or proximal and distal aortic replacement. The main characteristics of these patients are summarized in Table 1.
|
The proximal anastomosis of the reversed elephant trunk was created first by invaginating the future aortic arch graft into the descending aortic prosthesis (Figure 1, A). After deairing and flushing of debris out of the aorta, proximal reperfusion was reinstituted at a flow rate of 2.5 L/min through a 24F cannula introduced into the side arm of the vascular prosthesis (Anteflow; Vaskutek, SulzerMedica, Winterthur, Switzerland), with the tip of the cannula being advanced into the distal aortic arch to prevent unfolding of the reversed graft portion.
|
, B). These 4 patients had a chronic aortic dissection; a large communication was created between the true and the false channels by incising the intimal flap over 5 to 6 cm below the distal anastomosis. In patients with deep hypothermia, circulatory arrest was shorter (20 ± 11 vs 35 ± 13 minutes), but the rewarming period (45 ± 14 minutes) was comparable with that necessary in a control group of patients (n = 20) who underwent aortic arch replacement with the classic elephant trunk technique through a median sternotomy (51 ± 17 minutes).
The proper position of the elephant trunk was assessed intraoperatively by means of transesophageal echocardiography and postoperatively by means of computed tomography.
Nine patients underwent subsequent aortic arch replacement by use of the reversed prosthetic portion after a mean interval of 8 ± 5.5 months. In these patients the second stage was performed through a median sternotomy. Extracorporeal perfusion was instituted through cannulation of the ascending aorta and right atrium. During deep hypothermic circulatory arrest, the invaginated reversed elephant trunk was withdrawn from the proximal descending aortic graft with a nerve hook, unfolded, and used for arch replacement. When the repair had to be extended into the ascending aorta or into the aortic root, the arch graft was connected to another supracoronary Anteflow prosthesis or to a composite graft.
Two patients received distal extension with the distal portion of the free-floating graft after a mean interval of 14 ± 4 months. Both underwent subsequent replacement of the suprarenal and infrarenal aorta with a bifurcated graft, with reinsertion of the visceral branches during a single crossclamping period.
Five patients are still being observed until the contiguous aortic size is large enough to require an operation, and one 74-year-old patient declined a second-stage operation.
Results
All data related to total perfusion time, circulatory arrest, and aortic crossclamping time are summarized in Table 2. There was no hospital mortality (30 days) in this small group of patients. One patient had myocardial infarction; another had a minor stroke but had completely recovered by hospital discharge; and 2 patients had prolonged elevation of serum creatinine levels of greater than 200 µmol/L. No patient had aortic rupture, malperfusion caused by the technique itself, or thromboembolic complications during the waiting interval between the first and the second operations. All patients were seen in our outpatient clinic or were contacted for follow-up. After a mean observation time of 22 ± 8 months, there was neither late mortality nor significant complications.
|
A substantial number of patients with disease of the thoracic aorta may have involvement of more than one aortic segment and concomitant true aneurysmatic and dissecting disease. 8 In these patients staged aortic replacement competes with single-stage aortic repair, which may be associated with an increased perioperative risk mainly determined by neurologic injury, parenchymal damage to the left lung caused by retraction, and hemorrhagic complications.
Usually, staged aortic repair consists of replacement of the proximal lesion (ascending aorta–aortic arch) first, followed by repair of the descending aorta after a short recovery period. In this situation the classic elephant trunk technique represents probably the most suitable and reproducible option.
However, in some patients the descending aorta has to be replaced first because of symptoms or local problems, such as intramural hematoma, hemothorax, and contained rupture. For patients with these symptoms, the reversed elephant trunk technique is an interesting option that simplifies subsequent aortic arch replacement because the distal anastomosis below the left subclavian artery is already performed. We did not observe any mechanical complications related to the length and the position of the elephant trunk itself (eg, kinking or obstruction or partial unfolding of the free-floating graft portion). Surprisingly, no macroscopic clots were found between the 2 layers of the graft, and clinically perceptible thromboembolic events were observed in this small series, despite the fact that a majority of patients did not receive sodium warfarin (Coumadin) treatment.
To prevent uncontrolled unfolding of the reversed elephant trunk portion during the second step, we recommend cannulating the ascending aorta for cooling of the patient.
We have successfully used this technique in patients with chronic type A dissection and contained rupture of the descending aorta, in those with type B dissection and retrograde extension into the aortic arch only, and in patients with multifocal thoracic aortic disease in whom the descending aorta had to be replaced first. Shiiya and colleagues 9 reported a similar experience in patients with Marfan syndrome. Although aortic arch repair after prior replacement of the descending aorta is technically feasible, 8 it is obvious that the presence of a reversible elephant trunk shortens the period of circulatory arrest and the overall aortic crossclamping time during subsequent aortic arch operation. Looking at our own experience, we are able to confirm the following benefit: the mean circulatory arrest time for the classic elephant trunk technique was 35 ± 13 minutes (n = 20), whereas it was only 20 ± 11 minutes for the patients in this series (P < .01). Because selective antegrade cerebral perfusion is used only when a prolonged circulatory arrest (>20-30 minutes) is anticipated, only a small number of these patients received this type of cerebral protection.
In summary, the main advantages of the reversed elephant trunk technique are as follows: (1) improved exposure of the supra-aortic vessels as a result of elimination of the distal aortic arch anastomosis; (2) reduction of the circulatory arrest time required for subsequent complete aortic arch replacement; (3) reduction of the risk of hemorrhage; and (4) combining of the reversed elephant trunk technique with the distal technique (ie, the bidirectional elephant trunk technique) for both proximal and distal extension in a simple way.
Acknowledgments
Dedicated to Ulrich Althaus, MD, Professor of Surgery and former Chairman of the Department of Cardiovascular Surgery at the University of Berne, Switzerland, in honor of his 65th birthday.
References
This article has been cited by other articles:
|
|
 |
|
  M. Karck and H. Kamiya Progress of the treatment for extended aortic aneurysms; is the frozen elephant trunk technique the next standard in the treatment of complex aortic disease including the arch? Eur. J. Cardiothorac. Surg., June 1, 2008; 33(6): 1007 - 1013. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. S. Coselli, S. A. LeMaire, S. A. Carter, and L. D. Conklin The Reversed Elephant Trunk Technique Used for Treatment of Complex Aneurysms of the Entire Thoracic Aorta Ann. Thorac. Surg., December 1, 2005; 80(6): 2166 - 2172. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. Okada, T. Sueda, K. Orihashi, K. Imai, and K. Sato A modified elephant trunk technique: The 3-fold elephant trunk technique J. Thorac. Cardiovasc. Surg., December 1, 2005; 130(6): 1720 - 1722. [Full Text] [PDF]
|
|
|
|
|
|
M. Karck, A. Chavan, N. Khaladj, H. Friedrich, C. Hagl, and A. Haverich The frozen elephant trunk technique for the treatment of extensive thoracic aortic aneurysms: operative results and follow-up Eur. J. Cardiothorac. Surg., August 1, 2005; 28(2): 286 - 290. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. P. Carrel, F. S. Eckstein, and J. Schmidli Complete Replacement of the Supraaortic Branches and of the Aortic Arch Facilitated by a "Reversed" Elephant Trunk Ann. Thorac. Surg., June 1, 2005; 79(6): 2159 - 2159. [Full Text] [PDF]
|
|
|
|
|
|
M. Yoshitatsu, F. Nomura, K. Toda, A. Katayama, K. Tamura, K. Katayama, and K. Ihara The "Eaves" Technique for Distal Anastomosis in Aortic Arch Replacement Ann. Thorac. Surg., April 1, 2005; 79(4): 1422 - 1424. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Carrel, L. Beyeler, A. Schnyder, P. Zurmuhle, P. Berdat, J. Schmidli, and F. S. Eckstein Reoperations and late adverse outcome in Marfan patients following cardiovascular surgery Eur. J. Cardiothorac. Surg., May 1, 2004; 25(5): 671 - 675. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |
