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Aortic Root Enlargement During Aortic Valve Replacement: Nicks and Manouguian Techniques
Aortic Root Enlargement During Aortic Valve Replacement: Nicks and Manouguian Techniques Kendra J. Grubb, MD, MHA Aortic valve replacement can be complicated by a small aortic annulus necessitating the placement of an undersized prosthetic valve. In an effort to avoid prosthesis-patient mismatch, root enlargement techniques have been utilized. Herein is a review of the Manouguian and Nicks techniques for posterior root enlargement. Operative Techniques in Thoracic and Cardiovasculary Surgery ]:]]]-]]] r 2016 Elsevier Inc. All rights reserved.
KEYWORDS aortic root enlargement, prosthesis-patient mismatch, Nicks, Manouguian
Introduction
A
ortic valve replacement is a common operation but can be complicated by a small aortic annulus necessitating the insertion of an aortic valve prosthesis of 21 mm or less in size. Prosthesis-patient mismatch can result and has been associated with worse outcomes, including increased left ventricular work, reduced left ventricular mass regression, and has also been associated with increased mortality in some studies.1,2 Although controversy remains regarding the clinical significance of prosthesis-patient mismatch, an increased transvalvular gradient is seen that certainly could be significantly elevated with exercise especially in younger active patients.3 Posterior aortic root enlargement can be performed to allow for implantation of a larger size valve. Nicks and colleagues first proposed posterior root enlargement in 1970. The Nicks technique facilitated placement of a larger size aortic valve prosthesis by extending the aortotomy posteriorly through the noncoronary sinus across the aortic ring and inserting a patch to augment the annulus.4 Subsequently, Manouguian et al5 demonstrated a similar Department of Cardiovascular and Thoracic Surgery, School of Medicine, University of Louisville, Louisville, KY Address reprint requests to Kendra J. Grubb, MD, MHA, Department of Cardiovascular and Thoracic Surgery, School of Medicine, University of Louisville, 201 Abraham Flexner Way, Suite 1200, Louisville, KY 40202 E-mail: [email protected]
1522-2942/$-see front matter r 2016 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1053/j.optechstcvs.2016.02.004
technique, extending the incision through the commissure between the left and noncoronary sinus and into the anterior mitral leaflet. The Manouguian technique resulted in 1025 mm of root enlargement and the possibility of implanting a valve up to 2 sizes larger than what the native annulus could accommodate. Aortic root enlargement has been shown to be safe and without increased operative risk of death in recent studies.6
Operative Technique Herein is a review of the Manouguian and Nicks techniques for posterior root enlargement during aortic valve replacement, as seen from the operating surgeon's view. The reconstruction would be described from the Manouguian technique (Figs. 1-11).
Conclusion Posterior root enlargement is a useful technique for the management of a small aortic root and annulus and may result in lower transvalvular gradients and better functional outcomes. Although root enlargement is rarely necessary, the techniques should remain in the armamentarium of cardiac surgeons. The procedures require additional technical skill, but the results of the aortic root enlargement should not
1
K.J. Grubb
2
Left coronary sinus Left coronary a. Cut edge of resected cusp
Right coronary a.
Area of conduction
Right noncoronary commissure
Left noncoronary commissure
Noncoronary sinus
Subaortic fibrous curtain Anterior mitral leaflet
Figure 1 Relevant surgical anatomy and the aortic valve as seen from the surgeons view. The valve leaflets have been excised to demonstrate the aortic annulus. Posterior enlargement of the aortic root and annulus can be achieved by extending the aortotomy through the noncoronary sinus across the aortic annulus (Nicks) or alternatively the incision can be extended posteriorly though the commissure at the left and noncoronary sinus onto the anterior mitral valve leaflet (Manouguian).
Nicks and Manouguian techniques
3
Pulmonary trunk Aorta
Right ventricle
Pericardium Right atrium Right coronary a. Figure 2 Surgical exposure is gained via a median sternotomy and a pericardial well is created. A survey of the anatomy is completed. The aorta is palpated for calcification and if necessary an epiaortic ultrasound is used to identify disease-free regions of the aorta for cannulation and placement of the crossclamp.
K.J. Grubb
4
Aorta
Right atrium
Figure 3 Standard cannulation for cardiopulmonary bypass is completed with an aortic cannula in the distal ascending aorta and a venous drainage cannula in the right atrial appendage. Cardioplegia cannulas are placed for retrograde and antegrade delivery of cardioplegia. An anterior aortic root vent is placed and a left ventricular vent can be placed in the right superior pulmonary vein (not pictured).
Nicks and Manouguian techniques
Ostium of left coronary a.
5
Cut edge of resected noncoronary cusp
Left noncoronary commissure
Right coronary a.
Figure 4 After the aorta is cross-clamped and the heart is arrested, an anterior transverse aortotomy is made. The valve is visualized through the initial aortotomy and the incision is extended obliquely toward the noncoronary sinus. The aortic valve leaflets are resected and annular calcium debrided. The valve is sized using standard valve sizers.
K.J. Grubb
6
A Manouguian B
Nicks C
Manouguian
Nicks Figure 5 (A) Posterior aortic root enlargement can be achieved by 2 techniques. (B) For the Manouguian technique, the incision is continued further posteriorly and across the aortic annulus at the commissure between the left coronary sinus and the noncoronary sinus and into the aortic-mitral continuity. This approach can be extended onto the anterior leaflet of the mitral valve to gain additional enlargement of the annulus. The roof of the left atrium must be identified and swept away from the aorta and care must be taken to preserve the mitral valve leaflets and chordal attachments. (C) Alternatively, the aortotomy is continued across the aortic annulus in the mid-portion of the noncoronary sinus and into the fibrous subaortic curtain, for a Nicks technique.
Nicks and Manouguian techniques
7
Beginning valvuloplasty with ventricular aspect of patch
Figure 6 A patch of bovine pericardium, Dacron, or autologous treated pericardium is used to reconstruct the aortic defect; we prefer to use bovine pericardium. A 4-0 polypropylene suture is started at the apex of the aortotomy and extended in a running fashion on both sides of the annular defect. Typically, the suture is continued approximately 2 cm beyond the native annulus.
K.J. Grubb
8
A Checking annulus size & commissure placement with valve sizer
Figure 7 (A) The valve sizer for the anticipated prosthetic valve is placed in the aortic annulus to confirm proper sizing and position of the valve. Using the model of the sewing ring, the position of the valve in the annulus is assessed and the coronary ostia are identified. (B) The neo-commissure can then be estimated based on the position of on the patch and marked.
increase operative risk. With this technique, it is possible to
Nicks and Manouguian techniques
B
9
Marking location of commissure placement
Figure 7 (continued)
K.J. Grubb
10
Pledgeted annular sutures placed for securing new aortic valve
Figure 8 Similar to an aortic valve replacement in a native annulus, we use a noneverting, horizontal mattress technique with pledgeted 2-0 nonabsorbable braided sutures around the annulus. At the transition zone and augmented segment, the pledgeted sutures are placed from outside the patch, into the aorta, to complete the reconstruction of the annulus. Alternatively, nonpledgeted sutures can be used for the native annulus, but pledgeted sutures should be used on the patch and to bridge the patch to aorta suture line.
Nicks and Manouguian techniques
11
Continued inclusion of patch with closure of aortotomy
Figure 9 The sutures are passed through the sewing cuff and the valve is seated at the annulus. After all sutures are tied, a careful inspection of the annulus for proper seating is completed and the coronary ostia are visualized to confirm no sign of obstruction.
12
K.J. Grubb
Figure 10 A 4-0 polypropylene suture is started at the aortotomy, opposite the patch, and run in a continuous fashion to the middle of the aortotomy. The patch is trimmed to the size of the remaining defect and the original 4-0 polypropylene sutures are continued around the patch to complete the closure of the aortotomy.
Nicks and Manouguian techniques
13
Aortotomy closed with inclusion of patch
Figure 11 A 4-0 polypropylene suture is started at the aortotomy, opposite the patch, and run in a continuous fashion to the middle of the aortotomy. The patch is trimmed to the size of the remaining defect and the original 4-0 polypropylene sutures are continued around the patch to complete the closure of the aortotomy.
implant a valve 2 sizes larger than what the native annulus would normally accept.
References 1. Blackstone EH, Cosgrove DM, Jamieson WR, et al: Prosthesis size and long-term survival after aortic valve replacement. J Thorac Cardiovasc Surg 126(3):783–796, 2003 2. Head SJ, Mokhles MM, Osnabrugge RL, et al: The impact of prosthesis-patient mismatch on long-term survival after aortic valve replacement: A systematic review and meta-analysis of 34 observational studies comprising 27,186 patients with 133,141 patient-years. Eur Heart J 33(12):1518–1529, 2012
3. Kulik A, Al-Saigh M, Chan V, et al: Enlargement of the small aortic root during aortic valve replacement: Is there a benefit?. Ann Thorac Surg 85 (1):94–100, 2008 4. Nicks R, Cartmill T, Bernstein L: Hypoplasia of the aortic root. The problem of aortic valve replacement. Thorax 25(3):339–346, 1970 5. Manouguian S, Seybold-Epting W: Patch enlargement of the aortic valve ring by extending the aortic incision into the anterior mitral leaflet. New operative technique. J Thorac Cardiovasc Surg 78(3):402–412, 1979 6. Dhareshwar J, Sundt 3rd TM, Dearani JA, Schaff HV, Cook DJ, Orszulak TA: Aortic root enlargement: what are the operative risks?. J Thorac Cardiovasc Surg 134(4):916–924, 2007
KEYWORDS aortic root enlargement, prosthesis-patient mismatch, Nicks, Manouguian
Introduction
A
ortic valve replacement is a common operation but can be complicated by a small aortic annulus necessitating the insertion of an aortic valve prosthesis of 21 mm or less in size. Prosthesis-patient mismatch can result and has been associated with worse outcomes, including increased left ventricular work, reduced left ventricular mass regression, and has also been associated with increased mortality in some studies.1,2 Although controversy remains regarding the clinical significance of prosthesis-patient mismatch, an increased transvalvular gradient is seen that certainly could be significantly elevated with exercise especially in younger active patients.3 Posterior aortic root enlargement can be performed to allow for implantation of a larger size valve. Nicks and colleagues first proposed posterior root enlargement in 1970. The Nicks technique facilitated placement of a larger size aortic valve prosthesis by extending the aortotomy posteriorly through the noncoronary sinus across the aortic ring and inserting a patch to augment the annulus.4 Subsequently, Manouguian et al5 demonstrated a similar Department of Cardiovascular and Thoracic Surgery, School of Medicine, University of Louisville, Louisville, KY Address reprint requests to Kendra J. Grubb, MD, MHA, Department of Cardiovascular and Thoracic Surgery, School of Medicine, University of Louisville, 201 Abraham Flexner Way, Suite 1200, Louisville, KY 40202 E-mail: [email protected]
1522-2942/$-see front matter r 2016 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1053/j.optechstcvs.2016.02.004
technique, extending the incision through the commissure between the left and noncoronary sinus and into the anterior mitral leaflet. The Manouguian technique resulted in 1025 mm of root enlargement and the possibility of implanting a valve up to 2 sizes larger than what the native annulus could accommodate. Aortic root enlargement has been shown to be safe and without increased operative risk of death in recent studies.6
Operative Technique Herein is a review of the Manouguian and Nicks techniques for posterior root enlargement during aortic valve replacement, as seen from the operating surgeon's view. The reconstruction would be described from the Manouguian technique (Figs. 1-11).
Conclusion Posterior root enlargement is a useful technique for the management of a small aortic root and annulus and may result in lower transvalvular gradients and better functional outcomes. Although root enlargement is rarely necessary, the techniques should remain in the armamentarium of cardiac surgeons. The procedures require additional technical skill, but the results of the aortic root enlargement should not
1
K.J. Grubb
2
Left coronary sinus Left coronary a. Cut edge of resected cusp
Right coronary a.
Area of conduction
Right noncoronary commissure
Left noncoronary commissure
Noncoronary sinus
Subaortic fibrous curtain Anterior mitral leaflet
Figure 1 Relevant surgical anatomy and the aortic valve as seen from the surgeons view. The valve leaflets have been excised to demonstrate the aortic annulus. Posterior enlargement of the aortic root and annulus can be achieved by extending the aortotomy through the noncoronary sinus across the aortic annulus (Nicks) or alternatively the incision can be extended posteriorly though the commissure at the left and noncoronary sinus onto the anterior mitral valve leaflet (Manouguian).
Nicks and Manouguian techniques
3
Pulmonary trunk Aorta
Right ventricle
Pericardium Right atrium Right coronary a. Figure 2 Surgical exposure is gained via a median sternotomy and a pericardial well is created. A survey of the anatomy is completed. The aorta is palpated for calcification and if necessary an epiaortic ultrasound is used to identify disease-free regions of the aorta for cannulation and placement of the crossclamp.
K.J. Grubb
4
Aorta
Right atrium
Figure 3 Standard cannulation for cardiopulmonary bypass is completed with an aortic cannula in the distal ascending aorta and a venous drainage cannula in the right atrial appendage. Cardioplegia cannulas are placed for retrograde and antegrade delivery of cardioplegia. An anterior aortic root vent is placed and a left ventricular vent can be placed in the right superior pulmonary vein (not pictured).
Nicks and Manouguian techniques
Ostium of left coronary a.
5
Cut edge of resected noncoronary cusp
Left noncoronary commissure
Right coronary a.
Figure 4 After the aorta is cross-clamped and the heart is arrested, an anterior transverse aortotomy is made. The valve is visualized through the initial aortotomy and the incision is extended obliquely toward the noncoronary sinus. The aortic valve leaflets are resected and annular calcium debrided. The valve is sized using standard valve sizers.
K.J. Grubb
6
A Manouguian B
Nicks C
Manouguian
Nicks Figure 5 (A) Posterior aortic root enlargement can be achieved by 2 techniques. (B) For the Manouguian technique, the incision is continued further posteriorly and across the aortic annulus at the commissure between the left coronary sinus and the noncoronary sinus and into the aortic-mitral continuity. This approach can be extended onto the anterior leaflet of the mitral valve to gain additional enlargement of the annulus. The roof of the left atrium must be identified and swept away from the aorta and care must be taken to preserve the mitral valve leaflets and chordal attachments. (C) Alternatively, the aortotomy is continued across the aortic annulus in the mid-portion of the noncoronary sinus and into the fibrous subaortic curtain, for a Nicks technique.
Nicks and Manouguian techniques
7
Beginning valvuloplasty with ventricular aspect of patch
Figure 6 A patch of bovine pericardium, Dacron, or autologous treated pericardium is used to reconstruct the aortic defect; we prefer to use bovine pericardium. A 4-0 polypropylene suture is started at the apex of the aortotomy and extended in a running fashion on both sides of the annular defect. Typically, the suture is continued approximately 2 cm beyond the native annulus.
K.J. Grubb
8
A Checking annulus size & commissure placement with valve sizer
Figure 7 (A) The valve sizer for the anticipated prosthetic valve is placed in the aortic annulus to confirm proper sizing and position of the valve. Using the model of the sewing ring, the position of the valve in the annulus is assessed and the coronary ostia are identified. (B) The neo-commissure can then be estimated based on the position of on the patch and marked.
increase operative risk. With this technique, it is possible to
Nicks and Manouguian techniques
B
9
Marking location of commissure placement
Figure 7 (continued)
K.J. Grubb
10
Pledgeted annular sutures placed for securing new aortic valve
Figure 8 Similar to an aortic valve replacement in a native annulus, we use a noneverting, horizontal mattress technique with pledgeted 2-0 nonabsorbable braided sutures around the annulus. At the transition zone and augmented segment, the pledgeted sutures are placed from outside the patch, into the aorta, to complete the reconstruction of the annulus. Alternatively, nonpledgeted sutures can be used for the native annulus, but pledgeted sutures should be used on the patch and to bridge the patch to aorta suture line.
Nicks and Manouguian techniques
11
Continued inclusion of patch with closure of aortotomy
Figure 9 The sutures are passed through the sewing cuff and the valve is seated at the annulus. After all sutures are tied, a careful inspection of the annulus for proper seating is completed and the coronary ostia are visualized to confirm no sign of obstruction.
12
K.J. Grubb
Figure 10 A 4-0 polypropylene suture is started at the aortotomy, opposite the patch, and run in a continuous fashion to the middle of the aortotomy. The patch is trimmed to the size of the remaining defect and the original 4-0 polypropylene sutures are continued around the patch to complete the closure of the aortotomy.
Nicks and Manouguian techniques
13
Aortotomy closed with inclusion of patch
Figure 11 A 4-0 polypropylene suture is started at the aortotomy, opposite the patch, and run in a continuous fashion to the middle of the aortotomy. The patch is trimmed to the size of the remaining defect and the original 4-0 polypropylene sutures are continued around the patch to complete the closure of the aortotomy.
implant a valve 2 sizes larger than what the native annulus would normally accept.
References 1. Blackstone EH, Cosgrove DM, Jamieson WR, et al: Prosthesis size and long-term survival after aortic valve replacement. J Thorac Cardiovasc Surg 126(3):783–796, 2003 2. Head SJ, Mokhles MM, Osnabrugge RL, et al: The impact of prosthesis-patient mismatch on long-term survival after aortic valve replacement: A systematic review and meta-analysis of 34 observational studies comprising 27,186 patients with 133,141 patient-years. Eur Heart J 33(12):1518–1529, 2012
3. Kulik A, Al-Saigh M, Chan V, et al: Enlargement of the small aortic root during aortic valve replacement: Is there a benefit?. Ann Thorac Surg 85 (1):94–100, 2008 4. Nicks R, Cartmill T, Bernstein L: Hypoplasia of the aortic root. The problem of aortic valve replacement. Thorax 25(3):339–346, 1970 5. Manouguian S, Seybold-Epting W: Patch enlargement of the aortic valve ring by extending the aortic incision into the anterior mitral leaflet. New operative technique. J Thorac Cardiovasc Surg 78(3):402–412, 1979 6. Dhareshwar J, Sundt 3rd TM, Dearani JA, Schaff HV, Cook DJ, Orszulak TA: Aortic root enlargement: what are the operative risks?. J Thorac Cardiovasc Surg 134(4):916–924, 2007