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Operative Techniques for Repair of Muscular Ventricular Septal Defects

2010; Elsevier BV; Volume: 15; Issue: 1 Linguagem: Inglês

10.1053/j.optechstcvs.2010.03.001

1532-8627

Marshall L. Jacobs, Jeffrey P. Jacobs,

Cardiac Structural Anomalies and Repair

A ventricular septal defect (VSD) is defined as "a hole between the ventricular chambers or their remnants."1The International Working Group for Defining the Nomenclatures for Paediatric and Congenital Heart Disease (Definitions Working Group) of The International Society for Nomenclature of Paediatric and Congenital Heart Disease.http://www.ipccc.net/Google Scholar A muscular ventricular septal defect is defined as "a VSD that has exclusively muscular borders."1The International Working Group for Defining the Nomenclatures for Paediatric and Congenital Heart Disease (Definitions Working Group) of The International Society for Nomenclature of Paediatric and Congenital Heart Disease.http://www.ipccc.net/Google Scholar This article reviews the spectrum of these muscular ventricular septal defects, the challenges they can pose, and the surgical techniques that have a demonstrated track record of efficacy, with special consideration for the following subtypes of muscular ventricular septal defects: (1) midmuscular VSD or midventricular VSD, (2) inlet muscular VSD, (3) apical muscular VSD, (4) anterior trabecular VSD or infundibular muscular VSD, and (5) multiple VSD and "Swiss-cheese" VSD. A "VSD" is a "ventricular septal defect" and is also known as an "interventricular communication." A VSD is defined as "a hole between the ventricular chambers or their remnants."1The International Working Group for Defining the Nomenclatures for Paediatric and Congenital Heart Disease (Definitions Working Group) of The International Society for Nomenclature of Paediatric and Congenital Heart Disease.http://www.ipccc.net/Google Scholar The VSD is defined on the basis of its margins as seen from the aspect of the morphologically right ventricle. In the setting of double outlet right ventricle, the defect provides the outflow from the morphologically left ventricle. In univentricular atrioventricular connections with functionally single left ventricle with an outflow chamber, the communication is referred to by some as a bulboventricular foramen. A muscular ventricular defect is defined as "a VSD that has exclusively muscular borders."1The International Working Group for Defining the Nomenclatures for Paediatric and Congenital Heart Disease (Definitions Working Group) of The International Society for Nomenclature of Paediatric and Congenital Heart Disease.http://www.ipccc.net/Google Scholar In an era when enthusiasm for transcatheter device closure of muscular VSDs is increasingly gaining attention and popularity, it is appropriate and important to review the spectrum of these defects, the challenges they can pose, and the surgical techniques that have a demonstrated track record of efficacy. This article considers these topics for the entire spectrum of muscular ventricular septal defects, a spectrum that includes the following subtypes (Fig. 1)2Jacobs J.P. Burke R.P. Quintessenza J.A. et al.Congenital Heart Surgery Nomenclature and Database Project: Ventricular septal defect The Annals of Thoracic SurgeryApril 2000 Supplement.Ann Thorac Surg. 2000; 69: S25-S35Abstract Full Text Full Text PDF PubMed Google Scholar:1Midmuscular VSD or midventricular VSD2Inlet muscular VSD3Apical muscular VSD4Anterior trabecular VSD or infundibular muscular VSD5Multiple VSD and "Swiss-cheese" VSD.This article does not discuss indications or surgical techniques for banding of the pulmonary artery, a palliative strategy that may be quite useful in specific situations including some neonates or infants with apical VSDs or multiple VSDs, as well as small patients with familial objections to blood transfusions, and patients with complex associated defects. A midmuscular VSD or midventricular VSD is defined as "a muscular VSD located in the central muscular septum."1The International Working Group for Defining the Nomenclatures for Paediatric and Congenital Heart Disease (Definitions Working Group) of The International Society for Nomenclature of Paediatric and Congenital Heart Disease.http://www.ipccc.net/Google Scholar This type of VSD is perhaps the most "straightforward" of the muscular ventricular septal defects; however, closure of this type of VSD can be challenging because of the possibility of multiple right-sided openings of a defect that is a single opening on the left ventricular side. Difficulty in identifying the true margins of the VSD among the multiple trabeculations of the right side of the ventricular septum represents the main difficulty in closing this type of VSD. It is often necessary to divide some of the coarse muscular trabeculations on the right ventricular surface of the septum to expose the true margins of the VSD.3de Leval M. Ventricular septal defects.in: Stark J. de Leval M. Surgery for Congenital Heart Defects (ed 2). WB Saunders, Philadelphia, PA1994Google Scholar, 4Serraf A. Lacour-Gayet F. Bruniaux J. et al.Surgical management of isolated multiple ventricular septal defects Logical approach in 130 cases.J Thorac Cardiovasc Surg. 1992; 103 (1992): 437-442PubMed Google Scholar, 5Kitagawa T. Durham III, L.A. Mosca R.S. et al.Technique and results in the management of multiple ventricular septal defects.J Thorac Cardiovasc Surg. 1998; 115: 848-856Abstract Full Text Full Text PDF PubMed Scopus (126) Google Scholar The coarse multiple trabeculations on the right ventricular side of the septum, including the moderator band and lower end of the septal band, can be divided to facilitate accurate exposure of midmuscular VSDs as necessary. This technique can facilitate successful closure of defects that may appear to be multiple but are in fact single defects with more than one opening on the right ventricular side.5Kitagawa T. Durham III, L.A. Mosca R.S. et al.Technique and results in the management of multiple ventricular septal defects.J Thorac Cardiovasc Surg. 1998; 115: 848-856Abstract Full Text Full Text PDF PubMed Scopus (126) Google Scholar Common options for closure of midmuscular VSDs include surgical closure via a right atriotomy, surgical closure via a right ventriculotomy, and transcatheter device closure. These defects can usually be approached surgically through the right atrium using a standard right atriotomy (Fig. 2A-C). Large defects are closed with a patch sutured to the margins of the VSD on the right ventricular side of the septum. An oversized patch may be used to close multiple VSDs. Kitagawa and colleagues have described "placing the patch on the left ventricular side of the VSD for more secure closure … . The sutures are brought back across the septum from the left to the right side and secured over felt buttresses away from the edges of the defect. The patch is held in position on the left side of the septum by the sutures and the higher left ventricular pressures" (Fig. 2B and C insets).5Kitagawa T. Durham III, L.A. Mosca R.S. et al.Technique and results in the management of multiple ventricular septal defects.J Thorac Cardiovasc Surg. 1998; 115: 848-856Abstract Full Text Full Text PDF PubMed Scopus (126) Google Scholar Smaller defects may be closed with pledgeted horizontal mattress sutures.3de Leval M. Ventricular septal defects.in: Stark J. de Leval M. Surgery for Congenital Heart Defects (ed 2). WB Saunders, Philadelphia, PA1994Google Scholar The atrioventricular node and bundle of His, as well as the main bundle branches of the conduction tissue, are all remote from the margins of this type of VSD. Only terminal portions of the bundle branches may be near this VSD.3de Leval M. Ventricular septal defects.in: Stark J. de Leval M. Surgery for Congenital Heart Defects (ed 2). WB Saunders, Philadelphia, PA1994Google Scholar At times, closure through a right atriotomy is difficult and a right ventriculotomy may be necessary. When a right ventriculotomy is performed, the VSD is first assessed through a right atriotomy. A vertical right ventriculotomy is then made at least 5 mm away from the left anterior descending coronary artery, to facilitate improved exposure of the VSD. Standard patch closure may be performed via the right ventriculotomy. Alternatively, an external buttress technique may be utilized through a right ventriculotomy. This technique uses two pledget strips, one inside the right ventricle and one outside the right ventricle, which are tightly approximated with multiple horizontal mattress sutures that are placed from below the defect through the anterior right ventricular free wall and tied over the pledget strip outside the heart (Fig. 3).3de Leval M. Ventricular septal defects.in: Stark J. de Leval M. Surgery for Congenital Heart Defects (ed 2). WB Saunders, Philadelphia, PA1994Google Scholar Several additional approaches to closing midmuscular VSDs have been described. A "sandwich technique" using a patch with one side on the right ventricular surface and one side on the left ventricular surface has also been described (Fig. 4A-F).6Yamaguchi M. Yoshimura N. Oka S. et al.Closure of muscular VSD by a sandwiching method via a coexisting larger VSD or an interatrial septostomy.in: Proceedings of the 3rd World Congress of Pediatric Cardiology and Cardiac Surgery; May 27-31, 2001. Toronto, Canada, Steering Committee of the 3rd World Congress of Pediatric Cardiology and Cardiac Surgery, Toronto, Canada2001Google Scholar, 7Ootaki Y. Yamaguchi M. Yoshimura N. et al.Surgical management of trabecular ventricular septal defects The sandwich technique.J Thorac Cardiovasc Surg. 2003; 125: 508-512Abstract Full Text Full Text PDF PubMed Scopus (29) Google Scholar, 8Murakami H. Yoshimura N. Takahashi H. et al.Closure of multiple ventricular septal defects by the felt sandwich technique: Further analysis of 36 patients.J Thorac Cardiovasc Surg. 2006; 132: 278-282Abstract Full Text Full Text PDF PubMed Scopus (14) Google Scholar, 9Brizard C.P. Olsson C. Wilkinson J.L. New approach to multiple ventricular septal defect closure with intraoperative echocardiography and double patches sandwiching the septum.J Thorac Cardiovasc Surg. 2004; 128: 684-692Abstract Full Text Full Text PDF PubMed Scopus (29) Google Scholar Bacha and colleagues have described perventricular device closure of muscular ventricular septal defects on the beating heart.10Bacha E.A. Cao Q.-L. Starr J.P. et al.Perventricular device closure of muscular ventricular septal defects on the beating heart: Technique and results.J Thorac Cardiovasc Surg. 2003; 126: 1718-1723Abstract Full Text Full Text PDF PubMed Scopus (145) Google Scholar This technique of perventricular device closure technique can be utilized for midmuscular VSDs and also muscular VSDs in other locations in the ventricular septum; we illustrate this technique in the section about apical VSDs. Finally, nonsurgical transcatheter device closure of muscular ventricular septal defects has been described (Fig. 5).Figure 5This diagram demonstrates nonsurgical transcatheter device closure of a muscular ventricular septal defect.11Holzer R. Balzer D. Cao Q.-L. et al.Amplatzer Muscular Ventricular Septal Defect InvestigatorsDevice closure of muscular ventricular septal defects using the Amplatzer muscular ventricular septal defect occluder: Immediate and mid-term results of a U.S. registry.J Am Coll Cardiol. 2004; 43: 1257-1263Abstract Full Text Full Text PDF PubMed Scopus (281) Google Scholar (A) A midmuscular VSD. (B) A catheter passed through the superior vena cava, right atrium, tricuspid valve, right ventricle, VSD, and left ventricle. (C) Release of the left ventricular side of the device. (D) Release of the right ventricular side of the device. (E) The device is completely deployed. LA = left atrium; LV = left ventricle; RA = right atrium; RV = right ventricle.View Large Image Figure ViewerDownload Hi-res image Download (PPT) An inlet muscular VSD is defined as "a muscular VSD located beneath the septal leaflet of the tricuspid valve."1The International Working Group for Defining the Nomenclatures for Paediatric and Congenital Heart Disease (Definitions Working Group) of The International Society for Nomenclature of Paediatric and Congenital Heart Disease.http://www.ipccc.net/Google Scholar An inlet muscular VSD is typically closed through a right atriotomy. The surgical technique is similar to that previously described for a midmuscular VSD (Fig. 2A-C). However, special care must be taken to avoid damage to the conduction tissue (Fig. 6).3de Leval M. Ventricular septal defects.in: Stark J. de Leval M. Surgery for Congenital Heart Defects (ed 2). WB Saunders, Philadelphia, PA1994Google Scholar In contradistinction to the more common perimembranous inlet VSD, the muscular inlet VSD is surrounded by a complete rim of muscular tissue. The atrioventricular conduction axis penetrates into the ventricles on the superior (or leftward) side of the inlet muscular VSD. This location of the conduction tissue in relation to the inlet muscular VSD is completely different from the location of the conduction tissue in a perimembranous VSD or an atrioventricular canal-type defect. In the muscular inlet VSD, the conduction tissue is close to the outlet aspect of the VSD, in other words, on the surgeon's left hand side when viewing the defect through the tricuspid valve in a heart in situs solitus with concordant atrioventricular connections. In this location, sutures must be placed superficially on the right ventricular side of the ventricular septum near the superior rim of the VSD. Because of the proximity to the atrioventricular valves and conduction tissue, this type of VSD is a poor candidate for closure with a device, and in some cases may not be amenable to closure with a device. Figure 6 demonstrates a heart with both a perimembranous VSD and a muscular inlet VSD approached through a right atriotomy and the tricuspid valve. The conduction tissue is in the bridge of muscle between the two VSDs. It is related to the perimembranous VSD and the muscular VSD in the usual position relative to each VSD. Because the bridge of muscle between the two VSDs contains the conduction tissue and may be quite narrow, these two VSDs should be closed with a single patch to avoid heart block.3de Leval M. Ventricular septal defects.in: Stark J. de Leval M. Surgery for Congenital Heart Defects (ed 2). WB Saunders, Philadelphia, PA1994Google Scholar, 12Bharati S. Lev M. Kirklin J.W. Cardiac Surgery and the Conduction System.in: Wiley, New York1983Google Scholar This situation wherein an inlet muscular VSD and a perimembranous VSD coexist is not analogous to the heart with multiple muscular defects. In the heart where an inlet muscular VSD and a perimembranous VSD coexist, closure with a single patch over both holes is recommended to avoid injury to the conduction system. In this heart, division or excision of the strip of muscle between the inlet muscular VSD and a perimembranous VSD is certain to destroy the conduction system and create permanent third-degree heart block. An apical muscular VSD is defined as "a muscular VSD located apically relative to the moderator band."1The International Working Group for Defining the Nomenclatures for Paediatric and Congenital Heart Disease (Definitions Working Group) of The International Society for Nomenclature of Paediatric and Congenital Heart Disease.http://www.ipccc.net/Google Scholar Apical muscular VSDs can be technically challenging to close. Closure through a right atriotomy can be especially difficult due to limited exposure. Closure options include surgical approaches through a right ventriculotomy or left ventriculotomy, hybrid approaches with perventricular device closure, and transcatheter device closure. Stellin and colleagues described surgical closure of apical ventricular septal defects through a right ventricular apical infundibulotomy (Fig. 7).13Stellin G. Padalino M. Milanesi O. et al.Surgical closure of apical ventricular septal defects through a right ventricular apical infundibulotomy.Ann Thorac Surg. 2000; 69: 597-601Abstract Full Text Full Text PDF PubMed Scopus (49) Google Scholar Tsang and colleagues described an alternative approach to close apical muscular VSDs through a through a modified apical right ventriculotomy (Fig. 8).14Tsang V.T. Hsia T.-Y. Yates R.W.M. et al.Surgical repair of supposedly multiple defects within the apical part of the muscular ventricular septum.Ann Thorac Surg. 2002; 73: 58-62Abstract Full Text Full Text PDF PubMed Scopus (27) Google Scholar Another alternative approach is through an apical left ventriculotomy. Although some authors have reported diminished left ventricular function or late aneurysm formation with this approach, the left ventricular apical approach can be very useful.3de Leval M. Ventricular septal defects.in: Stark J. de Leval M. Surgery for Congenital Heart Defects (ed 2). WB Saunders, Philadelphia, PA1994Google Scholar, 5Kitagawa T. Durham III, L.A. Mosca R.S. et al.Technique and results in the management of multiple ventricular septal defects.J Thorac Cardiovasc Surg. 1998; 115: 848-856Abstract Full Text Full Text PDF PubMed Scopus (126) Google Scholar, 15Singh A.K. de Leval M.R. Stark J. Left ventriculotomy for closure of muscular ventricular septal defects Treatment of choice.Ann Surg. 1977; 186: 577-580Crossref PubMed Scopus (34) Google Scholar, 16McDaniel N. Gutgesell H.P. Nolan S.P. et al.Repair of large muscular ventricular septal defects in infants employing left ventriculotomy.Ann Thorac Surg. 1989; 47: 593-594Abstract Full Text PDF PubMed Scopus (25) Google Scholar, 17Hannan R. Repair of large muscular ventricular septal defects in infants employing left ventriculotomy.Ann Thorac Surg. 1997; 63: 288-289PubMed Google Scholar The ventriculotomy incision should be kept as small as possible and limited to the true apex of the left ventricle (Fig. 9). Bacha and colleagues have described perventricular device closure of apical muscular VSDs on the beating heart (Fig. 10).10Bacha E.A. Cao Q.-L. Starr J.P. et al.Perventricular device closure of muscular ventricular septal defects on the beating heart: Technique and results.J Thorac Cardiovasc Surg. 2003; 126: 1718-1723Abstract Full Text Full Text PDF PubMed Scopus (145) Google ScholarFigure 8This figure shows closure of an apical muscular VSD through a modified apical right ventriculotomy as described by Tsang and colleagues.14Tsang V.T. Hsia T.-Y. Yates R.W.M. et al.Surgical repair of supposedly multiple defects within the apical part of the muscular ventricular septum.Ann Thorac Surg. 2002; 73: 58-62Abstract Full Text Full Text PDF PubMed Scopus (27) Google Scholar The patch to close the VSD is anchored to the left ventricular surface posteriorly, and within the right ventricular surface anteriorly. (A) The anatomy in short axis. (B) The anatomy in the four-chamber projection. Ant. = anterior; LV = left ventricle; RV = right ventricle; VSD = ventricular septal defect.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Figure 9This figure shows closure of an apical muscular VSD through a left ventricular apical approach.3de Leval M. Ventricular septal defects.in: Stark J. de Leval M. Surgery for Congenital Heart Defects (ed 2). WB Saunders, Philadelphia, PA1994Google Scholar, 5Kitagawa T. Durham III, L.A. Mosca R.S. et al.Technique and results in the management of multiple ventricular septal defects.J Thorac Cardiovasc Surg. 1998; 115: 848-856Abstract Full Text Full Text PDF PubMed Scopus (126) Google Scholar, 15Singh A.K. de Leval M.R. Stark J. Left ventriculotomy for closure of muscular ventricular septal defects Treatment of choice.Ann Surg. 1977; 186: 577-580Crossref PubMed Scopus (34) Google Scholar, 16McDaniel N. Gutgesell H.P. Nolan S.P. et al.Repair of large muscular ventricular septal defects in infants employing left ventriculotomy.Ann Thorac Surg. 1989; 47: 593-594Abstract Full Text PDF PubMed Scopus (25) Google Scholar, 17Hannan R. Repair of large muscular ventricular septal defects in infants employing left ventriculotomy.Ann Thorac Surg. 1997; 63: 288-289PubMed Google Scholar A small "fish-mouth"-type incision can be made at the apex of the left ventricle parallel to and away from the LAD. This allows exposure of the VSD. LAD = left anterior descending coronary artery; LV = left ventricle; RV = right ventricle.View Large Image Figure ViewerDownload Hi-res image Download (PPT)Figure 10(A-D) This figure shows closure of multiple muscular VSDs with perventricular placement of a device on a beating heart as described by Bacha and colleagues.10Bacha E.A. Cao Q.-L. Starr J.P. et al.Perventricular device closure of muscular ventricular septal defects on the beating heart: Technique and results.J Thorac Cardiovasc Surg. 2003; 126: 1718-1723Abstract Full Text Full Text PDF PubMed Scopus (145) Google Scholar (A) Multiple muscular VSDs with a wire across the largest VSD. In (B), the wire is positioned across the largest defect, and the sheath is positioned with its tip in the left ventricular cavity. The device is then pushed in and deployed by slowly pulling the sheath back. (C) Release of the left ventricular side of the device. (D) The device is completely deployed. VSD = ventricular septal defect.View Large Image Figure ViewerDownload Hi-res image Download (PPT) An outlet muscular VSD is defined as "a muscular VSD that opens between the septal band (septomarginal trabeculation) and the semilunar valve."1The International Working Group for Defining the Nomenclatures for Paediatric and Congenital Heart Disease (Definitions Working Group) of The International Society for Nomenclature of Paediatric and Congenital Heart Disease.http://www.ipccc.net/Google Scholar These defects include VSDs known as "anterior trabecular VSDs" and "infundibular muscular VSDs." This type of VSD is encountered in approximately 15 to 20% of patients with tetralogy of Fallot (TOF),3de Leval M. Ventricular septal defects.in: Stark J. de Leval M. Surgery for Congenital Heart Defects (ed 2). WB Saunders, Philadelphia, PA1994Google Scholar and may be a secondary VSD in TOF or the only VSD in TOF. Because of the proximity to the semilunar valves, this type of VSD is a poor candidate for closure with a device, and in some cases may not be amenable to closure with a device. The infundibular muscular VSD is separated from the conduction tissue inferiorly and posteriorly by the fusion of the posterior limb of the trabecula septomarginalis with the ventriculo-infundibular fold (Fig. 11).3de Leval M. Ventricular septal defects.in: Stark J. de Leval M. Surgery for Congenital Heart Defects (ed 2). WB Saunders, Philadelphia, PA1994Google Scholar Muscular outlet VSDs may be approached through the right atrium, right ventricle, or pulmonary artery. Most commonly, they are approached through a right ventriculotomy with division of muscle bundles to expose the VSD. Anterior defect exposure is sometimes facilitated by a transverse pulmonary arteriotomy.18Alsoufi B. Karamlou T. Osaki M. et al.Surgical repair of multiple muscular ventricular septal defects: The role of re-endocardialization strategy.J Thorac Cardiovasc Surg. 2006; 132: 1072-1080Abstract Full Text Full Text PDF PubMed Scopus (28) Google Scholar These VSDs are surrounded entirely by muscle and closed with a patch sewn to the margins of the defect. Multiple muscular VSDs represent a surgical challenge. The term "VSD, Type 4 (Muscular), Multiple-"Swiss-Cheese"" is defined by the Congenital Heart Surgery Database of The European Association for Cardio-Thoracic Surgery and The Society of Thoracic Surgeons (STS) as a heart where "more than three muscular VSDs exist."2Jacobs J.P. Burke R.P. Quintessenza J.A. et al.Congenital Heart Surgery Nomenclature and Database Project: Ventricular septal defect The Annals of Thoracic SurgeryApril 2000 Supplement.Ann Thorac Surg. 2000; 69: S25-S35Abstract Full Text Full Text PDF PubMed Google Scholar A variety of definitions have been used to define this entity,5Kitagawa T. Durham III, L.A. Mosca R.S. et al.Technique and results in the management of multiple ventricular septal defects.J Thorac Cardiovasc Surg. 1998; 115: 848-856Abstract Full Text Full Text PDF PubMed Scopus (126) Google Scholar, 19Fishberger S.B. Bridges N.D. Keane J.F. et al.Intraoperative device closure of ventricular septal defects.Circulation. 1993; 88: 205-209Google Scholar, 20Leca F. Karam J. Vouhè P.R. et al.Surgical treatment of multiple ventricular septal defects using a biologic glue.J Thorac Cardiovasc Surg. 1994; 107: 96-102PubMed Google Scholar including uncountable multiple VSDs.20Leca F. Karam J. Vouhè P.R. et al.Surgical treatment of multiple ventricular septal defects using a biologic glue.J Thorac Cardiovasc Surg. 1994; 107: 96-102PubMed Google Scholar Nevertheless, for the purpose of these databases, this term is utilized if four or more muscular VSDs exist, as defined by Serraf and colleagues.4Serraf A. Lacour-Gayet F. Bruniaux J. et al.Surgical management of isolated multiple ventricular septal defects Logical approach in 130 cases.J Thorac Cardiovasc Surg. 1992; 103 (1992): 437-442PubMed Google Scholar It is desirable to specify the number of orifices from both the left ventricular and the right ventricular aspects, because clearly, these may be different.1The International Working Group for Defining the Nomenclatures for Paediatric and Congenital Heart Disease (Definitions Working Group) of The International Society for Nomenclature of Paediatric and Congenital Heart Disease.http://www.ipccc.net/Google Scholar Challenges with multiple VSDs and a "Swiss-cheese" septum include the risk of conduction system injury in the area between VSDs, and the difficulty in identifying and closing all of the holes. A combination of any of the strategies previously described may be useful for the closure of multiple VSDs and a "Swiss-cheese" septum. Occasionally, a larger oversized patch may be used to cover multiple holes. Occasionally, multiple cardiac incisions may be necessary in the same operation, including combined right atriotomy, right ventriculotomy, and left ventriculotomy. A preoperatively placed cardiac catheter can allow accurate localization of muscular VSDs and especially apical muscular VSDs. The approach can improve visualization of the VSD from the right side of the heart and also minimize the size of the ventriculotomy required for satisfactory closure (Fig. 12).21Thomson J.D.R. Gibbs J.L. van Doorn C. Cardiac catheter guided surgical closure of an apical ventricular septal defect.Ann Thorac Surg. 2000; 70: 1402-1404Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar This strategy, as well as the sandwich technique previously described, may both be used to facilitate hybrid intraoperative device deployment. Multiple apical VSDs can be treated by apical exclusion using the "septal obliteration technique," where a patch is sewn in position to exclude a portion of the right ventricular apex from the remainder of the right ventricular cavity. This technique creates a "noncommunicating" left-to-right ventricular shunt at the "blind-ending" neoapical chamber that is separated from the remainder of the right ventricle by the patch of the "septal obliteration technique."22Black M.D. Shukla V. Rao V. et al.Repair of isolated multiple muscular ventricular septal defects: The septal obliteration technique.Ann Thorac Surg. 2000; 70: 106-110Abstract Full Text Full Text PDF PubMed Scopus (30) Google Scholar Finally, the team from Toronto has described a technique named "transatrial re-endocardialization" to close multiple muscular ventricular septal defects. Exposure is through a right atriotomy, although anterior defect exposure was sometimes facilitated by a transverse pulmonary arteriotomy. A ventriculotomy was not used to access the VSDs unless it was required for repair of associated defects. Identification of muscular VSDs was done by gentle probing of trabeculations with a right angle clamp to delineate a connection with the left ventricle. Probing was also done through a perimembranous VSD or through the interatrial septum, to help completely identify all muscular VSDs. Large VSDs were closed with patches. Multiple smaller VSDs were closed with transatrial re-endocardialization, using "6-0 or 7-0 polypropylene sutures with a BV1 or BV175 needle (Ethicon, Inc, Somerville, NJ) (Fig. 13). The septal trabeculations were approximated in two layers of superficial, endocardial running sutures. Each suture was started at the distal edge of a trabeculation and run in a double-layer, simple, continuous fashion to the other end of the trabeculation, where they were tied … . It was sometimes possible to close multiple trabeculations with the same suture."18Alsoufi B. Karamlou T. Osaki M. et al.Surgical repair of multiple muscular ventricular septal defects: The role of re-endocardialization strategy.J Thorac Cardiovasc Surg. 2006; 132: 1072-1080Abstract Full Text Full Text PDF PubMed Scopus (28) Google Scholar In the STS Congenital Heart Surgery Database, during the 4-year time period of 2005 through 2008 inclusive, 75,087 operations were analyzed.23Jacobs J.P. Jacobs M.L. Mavroudis C. et al.Executive summary: The Society of Thoracic Surgeons Congenital Heart Surgery Database—Tenth Harvest (January 1, 2005-December 31, 2008) The Society of Thoracic Surgeons (STS) and Duke Clinical Research Institute (DCRI), Duke University Medical Center, Durham, North Carolina, United States, Spring 2009 Harvest.http://www.sts.org/sections/stsnationaldatabase/publications/executive/article.htmlGoogle Scholar Of these 75,087 operations, 4752 were classified as having VSD repair as their primary procedure. Table 1 shows the incidence of the various subtypes of VSD that compose these 4752 operations.Table 1Incidence of the Various Subtypes of VSDVSD TypeNumberPercent of All VSDVSD, Single48210.1VSD, Type 1 (Subarterial) (Supracristal) (Conal septal defect) (Infundibular)3587.5VSD, Type 2 (Perimembranous) (Paramembranous) (Conoventricular)333070.1VSD, Type 3 (Inlet) (AV canal type)1423.0VSD, Type 4 (Muscular)1853.9VSD, Type: Gerbode type (LV-RA communication)160.3VSD, Multiple2395.0All VSD4752100.0AV, atrioventricular; LV, left ventricle; RA, right atrium; VSD, ventricular septal defect. Open table in a new tab AV, atrioventricular; LV, left ventricle; RA, right atrium; VSD, ventricular septal defect. Table 2 shows cardiopulmonary bypass time in minutes, as well as the rates of heart block, unplanned reoperation prior to hospital discharge, and discharge mortality, for the various subtypes of VSD.Table 2Bypass Time and Outcome Data for the Various Subtypes of VSDVSD TypeCPB Time (min)Heart BlockUnplanned ReoperationDischarge MortalityVSD, Single72.81.7%2.5%0.8%VSD, Type 1 (Subarterial) (Supracristal) (Conal septal defect) (Infundibular)72.70.6%2.2%0.6%VSD, Type 2 (Perimembranous) (Paramembranous) (Conoventricular)750.9%1.3%0.5%VSD, Type 3 (Inlet) (AV canal type)90.83.5%2.8%1.4%VSD, Type 4 (Muscular)79.92.7%4.3%1.1%VSD, Type: Gerbode type (LV-RA communication)67.90.0%0.0%0.0%VSD, Multiple111.22.9%2.5%1.7%AV, atrioventricular; CPB, cardiopulmonary bypass; LV, left ventricle; RA, right atrium; VSD, ventricular septal defect. Open table in a new tab AV, atrioventricular; CPB, cardiopulmonary bypass; LV, left ventricle; RA, right atrium; VSD, ventricular septal defect. These data from the STS Congenital Heart Surgery Database demonstrate the following concepts:1Multiple VSDs take longer to close.2When compared with the more common perimembranous VSD, the rate of heart block is three times higher with muscular VSDs and multiple VSDs.3When compared with the more common perimembranous VSD, the rate of unplanned reoperation is over four times higher with muscular VSDs and almost twice as high with multiple VSDs.4When compared with the more common perimembranous VSD, the rate of mortality before discharge from the hospital is over twice as high with muscular VSDs and over three times as high with multiple VSDs.In summary, the surgical management of muscular VSDs and multiple VSDs is a challenging area. These operations are associated with increased mortality and morbidity in comparison to closure of the more common perimembranous VSD. Congenital heart surgeons must be aware of a variety of techniques that are available to close muscular VSDs. The choice of the appropriate technique(s) is critical to the success of the surgical exercise.