|
|
||||||||
Ann Thorac Surg 2003;76:1962-1966
© 2003 The Society of Thoracic Surgeons
a Division of Thoracic and Cardiovascular Surgery, Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil
b Division of Cardiovascular Surgery, Beneficência Portuguesa Hospital of São Paulo, São Paulo, Brazil
Accepted for publication June 13, 2003.
* Address reprint requests to Dr Almeida de Oliveira, R. Barão de Bocaina, 140 Ap. 19o, São Paulo SP 01241-020, Brazil.
e-mail: dcioliveira{at}incor.usp.br
| Abstract |
|---|
|
|
|---|
METHODS: Between November 1979 and December 2001, 18 consecutive patients aged 18 to 61 years (mean, 31.8 ± 13.3 years) underwent extraanatomic bypass grafting to repair coarctation of the aortic arch. Six patients (33.3%) had recoarctation after previous repair through a left thoracotomy, and 3 (16.7%) had associated cardiac diseases. The operative technique used in all patients was ascending aorta-to-descending thoracic aorta bypass with a polyethylene terephthalate fiber (Dacron) graft through a median sternotomy and posterior pericardial approach.
RESULTS: Follow-up was completed in all patients, with a mean duration of 5.6 ± 5.7 years (range, 12 months to 22 years). The follow-up interval exceeded 10 years in 5 patients. No neurologic complications, early or late mortality, late reoperations, or graft complications occurred. Six patients (33.3%) had mild hypertension. All patients were asymptomatic with patent Dacron grafts confirmed by echocardiography. Magnetic resonance angiography, performed in 15 (83.3%) patients, revealed that the Dacron grafts were still patent at a mean interval of 4.0 ± 6.2 years (range, 5 days to 22 years) after repair.
CONCLUSIONS: Extraanatomic ascending aorta-to-descending thoracic aorta bypass grafting for repair of aortic arch coarctation in adults is safe, with low morbidity and no mortality. The favorable midterm results indicate this technique is a safe and less invasive means of repairing aortic arch coarctation or recoarctation in adults.
| Introduction |
|---|
|
|
|---|
In 1979, we repaired an aortic arch coarctation through a median sternotomy alone and exposed the descending thoracic aorta through the posterior pericardial approach; this avoided redo thoracotomy and manipulation of a coarctation with extensive calcification in a patient who had undergone previous surgery [8]. During the same year, Vijayanagar and associates [9] described this technique as a single surgical approach for the combined surgical management of aortic coarctation and aortic valvular insufficiency.
The present article reviews our 22 years of experience with extraanatomic ascending aorta-to-descending thoracic aorta bypass grafting, through a median sternotomy and posterior pericardial approach, for repair of coarctation of the aortic arch in adults. We report the results of early and midterm follow-up with clinical evaluation and magnetic resonance angiography.
| Patients and methods |
|---|
|
|
|---|
According to the nomenclature of Backer and Mavroudis [1], the aortic arch consists of three segments: the proximal transverse arch (arch between the innominate and left carotid arteries), the distal transverse arch (arch between the left carotid and left subclavian arteries), and the aortic isthmus (arch between the left subclavian artery and insertion of the patent ductus arteriosus). In our series, 2 patients (11.1%) had coarctation in the proximal transverse arch, 6 patients (33.3%) had coarctation in the distal transverse arch, and 10 patients (55.6%) had coarctation in the aortic isthmus. Of the patients with coarctation in the aortic isthmus, 6 (60.0%) had recoarctation after previous repair through a left thoracotomy, and 3 (30.0%) had associated cardiac diseases consisting of type A aortic dissection in one, aortic valve regurgitation in another, and complete atrioventricular block in the third.
The main indications for the extraanatomic approach through sternotomy in our patients were coarctation of the aorta localized to the transverse arch, recoarctation after previous repair through left thoracotomy, and coarctation of the aorta associated with other cardiac diseases. The latter were repaired during the same operative period, using the same surgical approach.
All 18 patients had systemic arterial hypertension and used at least one antihypertensive medication. Preoperatively, all patients underwent echocardiography with Doppler, and 12 patients underwent angiography. The mean peak systolic gradient across the coarctation was 70.0 ± 16.8 mm Hg (range, 45 to 80 mm Hg) by angiography and 55.0 ± 18.0 mm Hg (range, 40 to 75 mm Hg) by echocardiography.
Operative technique
In all patients, ascending aorta-to-descending thoracic aorta bypass grafting for repair of the coarctation was carried out through a median sternotomy and the posterior pericardial approach. The operations were performed on normothermic (36°C) cardiopulmonary bypass, with a beating heart. After full cardiopulmonary bypass had been established, the heart was retracted cephalic and superiorly, the retrocardiac descending thoracic aorta was palpated, and the posterior pericardium was incised longitudinally over the aorta. The descending thoracic aorta was then isolated and encircled for safety (Fig 1).
|
|
The grafts used for extraanatomic bypass were preclotted Dacron grafts ranging in size from 16 mm to 25 mm (mean, 20 mm), depending on the diameter of the descending aorta.
Postoperative course
The patients were admitted to the intensive care unit under mechanical ventilation and extubated after showing adequate respiratory effort, normal blood gas values, and hemodynamic stability. Blood samples, electrocardiograms, and chest roentgenograms were obtained routinely.
Follow-up
After discharge, all patients were followed up at our outpatient clinic or by their respective cardiologists. All patients underwent clinical evaluation and echocardiography during the postoperative period. Follow-up information was obtained between November 2000 and December 2001 from postoperative clinical consultations, physician's letters, and telephone interviews. Survival, cardiac events (eg, angina, cardiac insufficiency, reoperation, or cardiac death), neurologic events, other late complications from any cause, and quality of life were all analyzed. Clinical follow-up was completed in all patients and ranged in duration from 12 months to 22 years (mean, 5.6 ± 5.7 years). The follow-up interval exceeded 10 years in 5 patients.
After providing informed consent, 15 (83.3%) patients underwent postoperative angiography with magnetic resonance imaging for evaluation of the aorta and graft. This occurred between 5 days and 22 years (mean, 4.0 ± 6.2 year) after repair. Three asymptomatic patients with an excellent quality of life did not undergo the angiographic study because of transportation or personal problems.
Magnetic resonance imaging
All magnetic resonance imaging was performed on a 1.5-T SIGNA CV/i (GE Medical Systems, Waukesha, WI) magnet with high-performance gradients, specifically designed to acquire high-resolution cardiovascular images.
The pulse sequences used were as follows:
| Results |
|---|
|
|
|---|
Midterm clinical follow-up
During a clinical follow-up period ranging from 12 months to 22 years (mean, 5.6 ± 5.7 years), all patients were asymptomatic and reported excellent quality of life. Echocardiography showed patent grafts in all patients. No other surgical or interventional procedures were performed during this follow-up period. Twelve patients (66.7%) now have normal systemic arterial blood pressure (systolic
140 mm Hg and diastolic
90 mm Hg) without medications. Six patients (33.3%) have residual systemic arterial hypertension controlled with only one antihypertensive medication. (Three patients are using ß-blockers, 2 patients are using angiotensin-converting enzyme inhibitors, and 1 patient is using a diuretic.)
Postoperative magnetic resonance study
Between 5 days and 22 years (mean, 4.0 ± 6.2 years) after the surgery, 15 patients (83.3%) underwent angiographic studies with magnetic resonance imaging. The resultant images showed the aorta with patent Dacron extraanatomic grafts in all patients (Fig 3).
Five of these patients had follow-up intervals of longer than 10 years. No complications were observed with either the Dacron grafts or the aorta. The blood volume and flow velocity (approximately 1 m/s) in the descending thoracic aorta beyond the Dacron graft anastomotic site were normal, and the pressure gradient ranged from 2.5 to 4.0 mm Hg (mean, 3.1 ± 0.8 mm Hg).
|
| Comment |
|---|
|
|
|---|
Various factors (eg, location, extent of narrowed segment, associated aortic wall pathology) determine the appropriate type of repair. Although advances in cardiovascular surgery have made extensive aortic replacement possible, unusual circumstances may call for extraanatomic thoracic aortic bypass grafting [12]. For example, this technique is useful in adults, especially those with complex forms of aortic coarctation, coarctation of the aortic arch, aortic wall calcifications, or extensive collateral circulation. This population is at high risk for postoperative morbidity and mortality [13]. The end-to-end anastomosis and even interposition grafting used in anatomic repair place the patient at high risk for intraoperative or postoperative complications (eg, hemorrhage, recurrent laryngeal nerve damage, phrenic nerve paralysis, chylothorax, paraplegia) [1417]. Concern also exists about the frequency of late aneurysms after patch graft aortoplasty [18, 19].
Operations on the aortic arch are usually performed with cardiopulmonary bypass, deep hypothermia, and circulatory arrest [20]. However, in the presence of a coarctation proximal to the carotid vessels, the risk of hypoperfusion with cerebral ischemia is significant. Several technical modifications have been advocated in an attempt to decrease or eliminate these complications.
Methods of bypass grafting for the repair of aortic coarctation have evolved during the years. Disadvantages of earlier techniques include the need for redo left thoracotomy [21], a long graft (to reach the abdominal aorta), or an additional laparotomy incision [57, 22]. Use of left thoracotomy followed by sternotomy to make the proximal and distal anastomoses allowed for use of a smaller graft, but it required separate incisions [23]. In 1979, we successfully used a variation of the extraanatomic technique to repair an aortic arch coarctation in an adult; the bypass graft extended from the ascending aorta to the descending thoracic aorta and was placed through a sternotomy and a posterior pericardial approach [8]. Although this patient had undergone left thoracotomy 10 years earlier, repair of the coarctation had been impossible because of extensive calcification throughout the involved aortic segment, subsequent to the distal transverse arch. During the same year, Vijayanagar and colleagues [9] reported successful use of the same technique for combined aortic valve replacement and repair of coarctation.
This variation of the extraanatomic technique used by us [8] and Vijayanagar and coworkers [9] simplified the procedure. It requires only a small graft and median sternotomy with the posterior pericardial approach to access the descending thoracic aorta, thus avoiding thoracotomy or laparotomy. Other advantages of this technique are that (1) it allows access to the descending thoracic aorta above the diaphragm in a segment with less collateral circulation; (2) it avoids manipulation of a coarctation segment in which the aortic wall has structural alterations and extensive collateral circulation, principally in adults; (3) it avoids hypothermic circulatory arrest in the repair of aortic arch coarctation; (4) in recurrent aortic coarctation, it avoids the need for dissection in areas heavily scarred by the previous operation or with extensive arterial collateral circulation as a result of the aortic coarctation; (5) other cardiac pathology can be repaired simultaneously through the sternotomy; and (6) it can be performed without cardiopulmonary bypass in cases of isolated aortic arch coarctation [24]. However, we did not use this latter approach because our patients were adults, had various grades of left ventricular hypertrophy, or required simultaneous repair of other cardiac diseases.
We have obtained excellent surgical and angiographic results with extraanatomic aortic bypass grafting and have observed no postoperative neurologic complications, respiratory problems, coagulopathies, or mortality. Midterm follow-up results suggest the procedure effectively controls arterial hypertension, does not result in recoarctation or repeat operations for graft-related complications, and improves life expectancy. Other authors have also observed excellent results [2527], although there are few reports describing the late angiographic outcome [28].
Potential drawbacks to the use of prosthetic material for surgical repair are thrombosis, infection, and false aneurysm formation. Fifteen patients (83.3%) in our series underwent postoperative angiography with magnetic resonance imaging, at a mean interval of 4.0 ± 6.2 years after the repair. The follow-up interval exceeded 10 years in 5 patients. All Dacron grafts were patent with good flow, and no graft complications were observed. Recently, preoperative magnetic resonance imaging of the aorta has been shown to be helpful in planning the extraanatomic procedure.
We conclude that extraanatomic ascending aorta-to-descending thoracic aorta bypass with Dacron grafts through the posterior pericardial approach is a safe, effective, and less invasive technique for repairing aortic arch coarctation or recoarctation in adults. This procedure should be considered as a suitable alternative for select patients with aortic coarctation, such as patients with coarctation localized to the transverse arch, aortic wall calcifications, extensive collateral circulation, associated cardiac disease, or recoarctation after left thoracotomy.
| References |
|---|
|
|
|---|
This article has been cited by other articles:
![]() |
L. M. Pedersen, T. A. L. Pedersen, E. M. Pedersen, H. Hojmyr, K. Emmertsen, and V. E. Hjortdal Blood flow measured by magnetic resonance imaging at rest and exercise after surgical bypass of aortic arch obstruction Eur. J. Cardiothorac. Surg., March 1, 2010; 37(3): 658 - 661. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. A. Vohra, L. Adamson, and M. P. Haw Does surgical correction of coarctation of the aorta in adults reduce established hypertension? Interactive CardioVascular and Thoracic Surgery, January 1, 2009; 8(1): 123 - 127. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. S. Schoenhoff, P. A. Berdat, M. Pavlovic, A. Kadner, M. Schwerzmann, J.-P. Pfammatter, and T. P. Carrel Off-Pump Extraanatomic Aortic Bypass for the Treatment of Complex Aortic Coarctation and Hypoplastic Aortic Arch Ann. Thorac. Surg., February 1, 2008; 85(2): 460 - 464. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Laks, D. Marelli, M. Plunkett, and J. Myers Adult Congenital Heart Disease Card. Surg. Adult, January 1, 2008; 3(2008): 1431 - 1464. [Full Text] |
||||
![]() |
A. Aris, M. L. Maestre, and M. T. Subirana Reply to the Editor J. Thorac. Cardiovasc. Surg., January 1, 2007; 133(1): 278 - 278. [Full Text] [PDF] |
||||
![]() |
A. Aris, J. Cobiella, M. L. Maestre, and M. T. Subirana Ascending-descending aortic bypass with the aid of a heart-lifting device. J. Thorac. Cardiovasc. Surg., August 1, 2006; 132(2): 433 - 434. [Full Text] [PDF] |
||||
![]() |
V. Agarwal, I. Ramnarine, A. F. Corno, and M. Pozzi Recurrent coarctation in a patient with Alagille syndrome Interactive CardioVascular and Thoracic Surgery, December 1, 2005; 4(6): 514 - 516. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. A. Carr, J. J. Amato, and R. S.D. Higgins Long-Term Results of Surgical Coarctectomy in the Adolescent and Young Adult With 18-Year Follow-Up Ann. Thorac. Surg., June 1, 2005; 79(6): 1950 - 1956. [Abstract] [Full Text] [PDF] |
||||
![]() |
I Ramnarine Role of surgery in the management of the adult patient with coarctation of the aorta Postgrad. Med. J., April 1, 2005; 81(954): 243 - 247. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. P. Graham Jr The year in congenital heart disease J. Am. Coll. Cardiol., June 2, 2004; 43(11): 2132 - 2141. [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 |