- Email: [email protected]
How to avoid problems with reduction aortoplasty
386
CORRESPONDENCE
coronary implant sites and divide the graft completely if necessary. In some patients, the valve can be excised and replaced within the aortic root graft by placing sutures with pledgets below the aortic annulus, through the Dacron graft, and then through the sewing ring of the new valve. If this is not readily accomplished, the coronary arteries are detached, and the root is re-replaced. None of our patients with a pericardial valve conduit have needed reoperation to date. Four of our older stented porcine valve conduits have been replaced because of late tissue failure; there were no deaths. Dr Urbanski suggests the possibility of repairing the root aneurysm by the techniques of Sarsam and Yacoub [4] or David and co-workers [5] and then replacing the aortic valve inside the graft. The former technique would be a poor choice in this situation because of the risk of late dilatation of the aorta remaining beneath the valve commissures and concern about increased bleeding risk with the long suture lines in fragile aortic tissue in the sinus regions. Placement of the Dacron graft according to the latter reimplantation technique, followed by aortic valve replacement into the annulus inside the graft, is a possibility that could avoid the two problems already mentioned. Whether this technique would “simplify” a reoperation for late tissue failure of the valve is uncertain. The technique that we described is simple, safe, effective, and durable. Its main use is in older patients with small risk of reoperation. In our experience, reoperation can be conducted with low risk without modifying our recommended strategy of a simple conduit made from a stented pericardial valve and a Dacron graft. Alan D. Hilgenberg, MD Bassem N. Mora, MD Cardiac Surgical Division Massachusetts General Hospital Warren 735 55 Fruit St Boston, MA 02114 e-mail: [email protected]
Ann Thorac Surg 2004;78:384 –90
Fig 1. Operative technique for external wrapping. (A) Broken vertical lines on the diseased aorta indicate the planned full-thickness suture lines for creating the desired aortic diameter, preventing a textured intimal surface, and immobilizing the external graft. (B) Wrapped aorta. aortoplasty with external wrapping are due mostly to the aortoplasty technique during wrapping. Although there are several surgical techniques for reduction aortoplasty [2, 3], I routinely prefer the external wrapping technique without incising or excising of the diseased aorta (“sandwich technique”). The sandwich technique prevents complications and can be performed easily, even on the beating heart (off-pump) in select patients (Fig 1). In this procedure, the Dacron tube graft is tailored to the diseased aorta longitudinally using separate, full-thickness U sutures. I have performed 66 such operations with no late cardiacrelated mortality or morbidity. Four of the procedures were performed off-pump. Making a decision regarding a dilated ascending aorta during a coronary bypass operation is sometimes difficult because of the relatively high mortality and morbidity rates associated with replacement. This is especially
MISCELLANEOUS
References 1. Urbanski PP, Diegeler A, Siebel A, Zacher M, Hacker RW. Valved stentless composite graft: clinical outcomes and hemodynamic characteristics. Ann Thorac Surg 2003;75: 467–71. 2. Hilgenberg AD, Mora BN. Composite aortic root replacement with a bovine pericardial valve conduit. Ann Thorac Surg 2003;75:1338 –9. 3. Banbury MK, Cosgrove DM III, White JA, Blackstone EH, Frater RWM, Okies JE. Age and valve size effect on the long-term durability of the Carpentier-Edwards aortic pericardial bioprosthesis. Ann Thorac Surg 2001;72:753–7. 4. Sarsam MAI, Yacoub M. Remodeling of the aortic valve annulus. J Thorac Cardiovasc Surg 1993;105:435–8. 5. David TE, Feindel CM, Bos J. Repair of the aortic valve in patients with aortic insufficiency and aortic root aneurysm. J Thorac Cardiovasc Surg 1995;109:345–52.
How to Avoid Problems With Reduction Aortoplasty To the Editor: I read with interest the case report by Bauer and colleagues [1]. It clearly shows that using an external tubular Dacron graft for reduction aortoplasty, which is favored for its short- and longterm durability, can result in disaster if some rules are not respected. I believe that the problems encountered in reduction © 2004 by The Society of Thoracic Surgeons Published by Elsevier Inc
See page 317 true in patients with severe cardiac or noncardiac disease in whom prolonged cardiopulmonary bypass and aortic crossclamp times cannot be tolerated [4, 5]. In such instances, external wrapping on-pump or off-pump is a strong alternative to replacement. Sinan Arsan, MD Department of Cardiovascular Surgery University of Maltepe, School of Medicine Ataturk Cad. Cam Sk. No 3/A 81530 Maltepe, Istanbul, Turkey e-mail: [email protected]
References 1. Bauer M, Grauhan O, Hetzer R. Dislocated wrap after previous reduction aortoplasty causes erosion of the ascending aorta. Ann Thorac Surg 2003;75:583–4. 2. Baumgartner F, Omari B, Pak S, Ginzton L, Shapiro S, Milliken J. Reduction aortoplasty for moderately sized ascending aortic aneurysms. J Card Surg 1998;13:129 –32. Erratum in: J Card Surg 1998;13:227. 0003-4975/04/$30.00
Ann Thorac Surg 2004;78:384 –90
3. Robicsek F. A new method to treat fusiform aneurysms of the ascending aorta associated with aortic valve disease: an alternative to radical resection. Ann Thorac Surg 1982;34:92–4. 4. Crawford ES, Svensson LG, Coselli JS, Safi HJ, Hess KR. Surgical treatment of aneurysm and/or dissection of the ascending aorta, transverse aortic arch, and ascending aorta and transverse aortic arch: factors influencing survival in 717 patients. J Thorac Cardiovasc Surg 1989;98:659 –74. 5. Bauer M, Pasic M, Schaffarzyk R, et al. Reduction aortoplasty for dilatation of the ascending aorta in patients with bicuspid aortic valve. Ann Thorac Surg 2002;73:720 –4.
CORRESPONDENCE
387
ascending aorta associated with aortic valve disease: an alternative to radical resection. Ann Thorac Surg 1982;34:92–4. 3. Carrel T, von Segesser L, Jenni R, et al. Dealing with dilated ascending aorta during aortic valve replacement: advantages of conservative surgical approach. Eur J Cardio-thorac Surg 1991;5:137–43. 4. Bauer M, Pasic M, Schaffarzyk R, et al. Reduction aortoplasty for dilatation of the ascending aorta in patients with bicuspid aortic valve. Ann Thorac Surg 2002;73:720 –4. 5. Baumgartner F, Omari B, Pak S, Ginzton L, Shapiro S, Milliken J. Reduction aortoplasty for moderately sized ascending aortic aneurysms. J Card Surg 1998;13:129 –32.
Reply
We fully agree with Dr Arsan that reduction aortoplasty with external wrapping can result in severe complications when it is performed technically inadequately. As we [1] suggested in our case report, the main point is the secure anchoring and good fit of the Dacron wrap to avoid alterations in the underlying aortic wall. Robicsek [2], Carrel and co-authors [3], and our group [4] have described successful surgical methods for secure anchoring. Dr Arsan believes that the problems encountered in reduction aortoplasty with external wrapping are due mostly to the “annuloplasty technique” during wrapping. In the widely accepted aortoplasty techniques, however, an “annuloplasty” is not done. Standard aortoplasty technique consists of the excision of an oval segment of the ascending aorta, which is opened by an extensive longitudinal or S-shaped aortotomy from the aortic clamp into the noncoronary sinus [2–5]. Dr Arsan presents a new method of reduction aortoplasty he calls the “sandwich technique.” It is done without incising or excising the diseased aortic wall. The Dacron tube graft is fitted to the aorta longitudinally with the use of separate, fullthickness U sutures. The classic indications for reduction aortoplasty are poststenotic dilatation [3], dilatation of the ascending aorta in patients with a bicuspid aortic valve [4], and fusiform aneurysm of the ascending aorta [2]. The technique described by Dr Arsan can be applied to fusiform aneurysms without a diseased aortic valve; however, it is not feasible in the case of the first two indications. Also, we believe that his sandwich technique can have pitfalls if it is not carried out technically well. In conclusion, compared with the reduction aortoplasty technique, the spectrum of indications for the sandwich technique appears limited. However, in principle, Dr. Arsan’s method is feasible as an off-pump procedure, which can be an advantage in selected patients. Matthias Bauer, MD Onnen Grauhan, MD, PhD Roland Hetzer, MD, PhD Department of Cardiothoracic and Vascular Surgery Deutsches Herzzentrum Berlin Augustenburger Platz 1 13353 Berlin, Germany e-mail: [email protected]
References 1. Bauer M, Grauhan O, Hetzer R. Dislocated wrap after previous reduction aortoplasty causes erosion of the ascending aorta. Ann Thorac Surg 2003;75:583–4. 2. Robicsek F. A new method to treat fusiform aneurysms of the © 2004 by The Society of Thoracic Surgeons Published by Elsevier Inc
Gas Embolization From the Left Ventricle and Aortic Root: A Possible Side Effect of High-Flow Gas Insufflation During Coronary Artery Surgery To the Editor: High-flow gas insufflation is used routinely in off-pump coronary operations to maintain a bloodless field and facilitate the performance of the anastomoses. Its widespread use is recent, and concerns have been raised regarding the effect on the coronary endothelium, with implications for future graft patency [1]. However, no significant side effects of this method have been reported. We describe the case of a 76-year-old patient undergoing 4-vessel coronary artery bypass grafting, on bypass, in which the high-flow gas insufflation may have caused CO2 and possibly air to reach the aortic root and left ventricle. This patient’s coronary arteries were extremely calcified, and we were therefore reluctant to place periarterial slings to minimize blood flow. We therefore decided to use high-flow CO2 insufflation (3 to 5 L/min gas flow and normal saline 1 to 5 mL/min per the manufacturer’s instructions [Medtronic Clearview]) to facilitate the performance of the distal anastomoses. After completion of the aortosaphenous anastomoses, and before terminating bypass, sounds were heard indicative of the presence of gas in the left ventricle. On placement of a root vent, air was immediately released under some pressure. The patient was placed in the Trendelenberg position and the root vented for a prolonged period before bypass was stopped and the left ventricle was allowed to eject in the typical manner. An intraoperative tranoesophageal echocardiogram (TOE) showed no intracardiac lesion that may have predisposed to gas accumulation from the right heart. Myocardial preservation was achieved by using the intermittent aortic cross-clamping and ventricular fibrillation method. Thus the insertion of the cardioplegia cannula into the aortic root as the source of air was eliminated. After the operation a further TOE was obtained that confirmed the absence of any intracardiac defect. The patient had no focal signs but was confused for 10 days before slowly recovering function. A brain computed tomographic scan was normal. Because the heart had been neither opened nor vented, we can only assume that the coronary arteries were held patent by their extremely calcified walls and that high-flow gas insufflation may have forced CO2 and possibly air by the Venturi effect retrogradely into the aortic root and left ventricle. Although no regurgitation was seen on TOE, the aortic valve could have been “tripped” and rendered incompetent while the heart was positioned for the circumflex graft. During off-pump operations, the aortic root pressure is higher compared with on-pump operations, in which the heart and root are decompressed and in which it would be more difficult for gas to travel retrogradely. However, this may provide a reasonable explanation for the 0003-4975/04/$30.00
MISCELLANEOUS
To the Editor:
CORRESPONDENCE
coronary implant sites and divide the graft completely if necessary. In some patients, the valve can be excised and replaced within the aortic root graft by placing sutures with pledgets below the aortic annulus, through the Dacron graft, and then through the sewing ring of the new valve. If this is not readily accomplished, the coronary arteries are detached, and the root is re-replaced. None of our patients with a pericardial valve conduit have needed reoperation to date. Four of our older stented porcine valve conduits have been replaced because of late tissue failure; there were no deaths. Dr Urbanski suggests the possibility of repairing the root aneurysm by the techniques of Sarsam and Yacoub [4] or David and co-workers [5] and then replacing the aortic valve inside the graft. The former technique would be a poor choice in this situation because of the risk of late dilatation of the aorta remaining beneath the valve commissures and concern about increased bleeding risk with the long suture lines in fragile aortic tissue in the sinus regions. Placement of the Dacron graft according to the latter reimplantation technique, followed by aortic valve replacement into the annulus inside the graft, is a possibility that could avoid the two problems already mentioned. Whether this technique would “simplify” a reoperation for late tissue failure of the valve is uncertain. The technique that we described is simple, safe, effective, and durable. Its main use is in older patients with small risk of reoperation. In our experience, reoperation can be conducted with low risk without modifying our recommended strategy of a simple conduit made from a stented pericardial valve and a Dacron graft. Alan D. Hilgenberg, MD Bassem N. Mora, MD Cardiac Surgical Division Massachusetts General Hospital Warren 735 55 Fruit St Boston, MA 02114 e-mail: [email protected]
Ann Thorac Surg 2004;78:384 –90
Fig 1. Operative technique for external wrapping. (A) Broken vertical lines on the diseased aorta indicate the planned full-thickness suture lines for creating the desired aortic diameter, preventing a textured intimal surface, and immobilizing the external graft. (B) Wrapped aorta. aortoplasty with external wrapping are due mostly to the aortoplasty technique during wrapping. Although there are several surgical techniques for reduction aortoplasty [2, 3], I routinely prefer the external wrapping technique without incising or excising of the diseased aorta (“sandwich technique”). The sandwich technique prevents complications and can be performed easily, even on the beating heart (off-pump) in select patients (Fig 1). In this procedure, the Dacron tube graft is tailored to the diseased aorta longitudinally using separate, full-thickness U sutures. I have performed 66 such operations with no late cardiacrelated mortality or morbidity. Four of the procedures were performed off-pump. Making a decision regarding a dilated ascending aorta during a coronary bypass operation is sometimes difficult because of the relatively high mortality and morbidity rates associated with replacement. This is especially
MISCELLANEOUS
References 1. Urbanski PP, Diegeler A, Siebel A, Zacher M, Hacker RW. Valved stentless composite graft: clinical outcomes and hemodynamic characteristics. Ann Thorac Surg 2003;75: 467–71. 2. Hilgenberg AD, Mora BN. Composite aortic root replacement with a bovine pericardial valve conduit. Ann Thorac Surg 2003;75:1338 –9. 3. Banbury MK, Cosgrove DM III, White JA, Blackstone EH, Frater RWM, Okies JE. Age and valve size effect on the long-term durability of the Carpentier-Edwards aortic pericardial bioprosthesis. Ann Thorac Surg 2001;72:753–7. 4. Sarsam MAI, Yacoub M. Remodeling of the aortic valve annulus. J Thorac Cardiovasc Surg 1993;105:435–8. 5. David TE, Feindel CM, Bos J. Repair of the aortic valve in patients with aortic insufficiency and aortic root aneurysm. J Thorac Cardiovasc Surg 1995;109:345–52.
How to Avoid Problems With Reduction Aortoplasty To the Editor: I read with interest the case report by Bauer and colleagues [1]. It clearly shows that using an external tubular Dacron graft for reduction aortoplasty, which is favored for its short- and longterm durability, can result in disaster if some rules are not respected. I believe that the problems encountered in reduction © 2004 by The Society of Thoracic Surgeons Published by Elsevier Inc
See page 317 true in patients with severe cardiac or noncardiac disease in whom prolonged cardiopulmonary bypass and aortic crossclamp times cannot be tolerated [4, 5]. In such instances, external wrapping on-pump or off-pump is a strong alternative to replacement. Sinan Arsan, MD Department of Cardiovascular Surgery University of Maltepe, School of Medicine Ataturk Cad. Cam Sk. No 3/A 81530 Maltepe, Istanbul, Turkey e-mail: [email protected]
References 1. Bauer M, Grauhan O, Hetzer R. Dislocated wrap after previous reduction aortoplasty causes erosion of the ascending aorta. Ann Thorac Surg 2003;75:583–4. 2. Baumgartner F, Omari B, Pak S, Ginzton L, Shapiro S, Milliken J. Reduction aortoplasty for moderately sized ascending aortic aneurysms. J Card Surg 1998;13:129 –32. Erratum in: J Card Surg 1998;13:227. 0003-4975/04/$30.00
Ann Thorac Surg 2004;78:384 –90
3. Robicsek F. A new method to treat fusiform aneurysms of the ascending aorta associated with aortic valve disease: an alternative to radical resection. Ann Thorac Surg 1982;34:92–4. 4. Crawford ES, Svensson LG, Coselli JS, Safi HJ, Hess KR. Surgical treatment of aneurysm and/or dissection of the ascending aorta, transverse aortic arch, and ascending aorta and transverse aortic arch: factors influencing survival in 717 patients. J Thorac Cardiovasc Surg 1989;98:659 –74. 5. Bauer M, Pasic M, Schaffarzyk R, et al. Reduction aortoplasty for dilatation of the ascending aorta in patients with bicuspid aortic valve. Ann Thorac Surg 2002;73:720 –4.
CORRESPONDENCE
387
ascending aorta associated with aortic valve disease: an alternative to radical resection. Ann Thorac Surg 1982;34:92–4. 3. Carrel T, von Segesser L, Jenni R, et al. Dealing with dilated ascending aorta during aortic valve replacement: advantages of conservative surgical approach. Eur J Cardio-thorac Surg 1991;5:137–43. 4. Bauer M, Pasic M, Schaffarzyk R, et al. Reduction aortoplasty for dilatation of the ascending aorta in patients with bicuspid aortic valve. Ann Thorac Surg 2002;73:720 –4. 5. Baumgartner F, Omari B, Pak S, Ginzton L, Shapiro S, Milliken J. Reduction aortoplasty for moderately sized ascending aortic aneurysms. J Card Surg 1998;13:129 –32.
Reply
We fully agree with Dr Arsan that reduction aortoplasty with external wrapping can result in severe complications when it is performed technically inadequately. As we [1] suggested in our case report, the main point is the secure anchoring and good fit of the Dacron wrap to avoid alterations in the underlying aortic wall. Robicsek [2], Carrel and co-authors [3], and our group [4] have described successful surgical methods for secure anchoring. Dr Arsan believes that the problems encountered in reduction aortoplasty with external wrapping are due mostly to the “annuloplasty technique” during wrapping. In the widely accepted aortoplasty techniques, however, an “annuloplasty” is not done. Standard aortoplasty technique consists of the excision of an oval segment of the ascending aorta, which is opened by an extensive longitudinal or S-shaped aortotomy from the aortic clamp into the noncoronary sinus [2–5]. Dr Arsan presents a new method of reduction aortoplasty he calls the “sandwich technique.” It is done without incising or excising the diseased aortic wall. The Dacron tube graft is fitted to the aorta longitudinally with the use of separate, fullthickness U sutures. The classic indications for reduction aortoplasty are poststenotic dilatation [3], dilatation of the ascending aorta in patients with a bicuspid aortic valve [4], and fusiform aneurysm of the ascending aorta [2]. The technique described by Dr Arsan can be applied to fusiform aneurysms without a diseased aortic valve; however, it is not feasible in the case of the first two indications. Also, we believe that his sandwich technique can have pitfalls if it is not carried out technically well. In conclusion, compared with the reduction aortoplasty technique, the spectrum of indications for the sandwich technique appears limited. However, in principle, Dr. Arsan’s method is feasible as an off-pump procedure, which can be an advantage in selected patients. Matthias Bauer, MD Onnen Grauhan, MD, PhD Roland Hetzer, MD, PhD Department of Cardiothoracic and Vascular Surgery Deutsches Herzzentrum Berlin Augustenburger Platz 1 13353 Berlin, Germany e-mail: [email protected]
References 1. Bauer M, Grauhan O, Hetzer R. Dislocated wrap after previous reduction aortoplasty causes erosion of the ascending aorta. Ann Thorac Surg 2003;75:583–4. 2. Robicsek F. A new method to treat fusiform aneurysms of the © 2004 by The Society of Thoracic Surgeons Published by Elsevier Inc
Gas Embolization From the Left Ventricle and Aortic Root: A Possible Side Effect of High-Flow Gas Insufflation During Coronary Artery Surgery To the Editor: High-flow gas insufflation is used routinely in off-pump coronary operations to maintain a bloodless field and facilitate the performance of the anastomoses. Its widespread use is recent, and concerns have been raised regarding the effect on the coronary endothelium, with implications for future graft patency [1]. However, no significant side effects of this method have been reported. We describe the case of a 76-year-old patient undergoing 4-vessel coronary artery bypass grafting, on bypass, in which the high-flow gas insufflation may have caused CO2 and possibly air to reach the aortic root and left ventricle. This patient’s coronary arteries were extremely calcified, and we were therefore reluctant to place periarterial slings to minimize blood flow. We therefore decided to use high-flow CO2 insufflation (3 to 5 L/min gas flow and normal saline 1 to 5 mL/min per the manufacturer’s instructions [Medtronic Clearview]) to facilitate the performance of the distal anastomoses. After completion of the aortosaphenous anastomoses, and before terminating bypass, sounds were heard indicative of the presence of gas in the left ventricle. On placement of a root vent, air was immediately released under some pressure. The patient was placed in the Trendelenberg position and the root vented for a prolonged period before bypass was stopped and the left ventricle was allowed to eject in the typical manner. An intraoperative tranoesophageal echocardiogram (TOE) showed no intracardiac lesion that may have predisposed to gas accumulation from the right heart. Myocardial preservation was achieved by using the intermittent aortic cross-clamping and ventricular fibrillation method. Thus the insertion of the cardioplegia cannula into the aortic root as the source of air was eliminated. After the operation a further TOE was obtained that confirmed the absence of any intracardiac defect. The patient had no focal signs but was confused for 10 days before slowly recovering function. A brain computed tomographic scan was normal. Because the heart had been neither opened nor vented, we can only assume that the coronary arteries were held patent by their extremely calcified walls and that high-flow gas insufflation may have forced CO2 and possibly air by the Venturi effect retrogradely into the aortic root and left ventricle. Although no regurgitation was seen on TOE, the aortic valve could have been “tripped” and rendered incompetent while the heart was positioned for the circumflex graft. During off-pump operations, the aortic root pressure is higher compared with on-pump operations, in which the heart and root are decompressed and in which it would be more difficult for gas to travel retrogradely. However, this may provide a reasonable explanation for the 0003-4975/04/$30.00
MISCELLANEOUS
To the Editor: