Tricuspid Valve Repair in Single Ventricle: Timing and Techniques
2012; Elsevier BV; Volume: 15; Issue: 1 Linguagem: Inglês
10.1053/j.pcsu.2012.01.010
ISSN1876-4665
AutoresVictor Tsang, Shahzad G. Raja,
Tópico(s)Congenital Heart Disease Studies
ResumoTricuspid valve performance in the systemic circulation is known to have important implications for survival and functional status after univentricular palliation of hypoplastic left heart syndrome (HLHS). Moderate to severe tricuspid valve regurgitation is not an uncommon finding in patients with HLHS undergoing staged surgical reconstruction. It can result from either abnormal valve morphology or incomplete leaflet coaptation, or both. But first and foremost, any aortic arch re-obstruction must be excluded. Development of significant tricuspid regurgitation (TR) remains an obstacle in improving survival after the Norwood procedure and likely compromised functional health after the Fontan procedure. Thus, surgical intervention for minimizing tricuspid valve deterioration and significant TR seems pivotal to improving long-term outcomes for patients with HLHS. This article provides an overview of the etiology and mechanisms of development of significant TR, natural history, indications for surgical intervention, and focuses on timing, techniques, and clinical outcomes of tricuspid valve repair in the setting of single ventricle. Tricuspid valve performance in the systemic circulation is known to have important implications for survival and functional status after univentricular palliation of hypoplastic left heart syndrome (HLHS). Moderate to severe tricuspid valve regurgitation is not an uncommon finding in patients with HLHS undergoing staged surgical reconstruction. It can result from either abnormal valve morphology or incomplete leaflet coaptation, or both. But first and foremost, any aortic arch re-obstruction must be excluded. Development of significant tricuspid regurgitation (TR) remains an obstacle in improving survival after the Norwood procedure and likely compromised functional health after the Fontan procedure. Thus, surgical intervention for minimizing tricuspid valve deterioration and significant TR seems pivotal to improving long-term outcomes for patients with HLHS. This article provides an overview of the etiology and mechanisms of development of significant TR, natural history, indications for surgical intervention, and focuses on timing, techniques, and clinical outcomes of tricuspid valve repair in the setting of single ventricle. STAGED palliation for patients with hypoplastic left heart syndrome (HLHS) has improved significantly over the past two decades, with hospital survivals reaching 93% for the Norwood procedure.1Tweddell J.S. Hoffman G.M. Mussatto K.A. et al.Improved survival of patients undergoing palliation of hypoplastic left heart syndrome: lessons learned from 115 consecutive patients.Circulation. 2002; 106: I82-I89PubMed Google Scholar However, the inter-stage mortality after the Norwood procedure remains an important issue (4% to 15% between the first 2 stages).1Tweddell J.S. Hoffman G.M. Mussatto K.A. et al.Improved survival of patients undergoing palliation of hypoplastic left heart syndrome: lessons learned from 115 consecutive patients.Circulation. 2002; 106: I82-I89PubMed Google Scholar, 2Azakie T. Merklinger S.L. McCrindle B.W. et al.Evolving strategies and improving outcomes of the modified Norwood procedure: a 10-year single-institution experience.Ann Thorac Surg. 2001; 72: 1349-1353Abstract Full Text Full Text PDF PubMed Scopus (207) Google Scholar, 3Mahle W.T. Spray T.L. Gaynor J.W. et al.Unexpected death after reconstructive surgery for hypoplastic left heart syndrome.Ann Thorac Surg. 2001; 71: 61-65Abstract Full Text Full Text PDF PubMed Scopus (117) Google Scholar The recent report from a randomized trial comparing shunt types documented transplantation-free survival at 12 months in the range of 64% to 74%.4Ohye R.G. Sleeper L.A. Mahony L. et al.Comparison of shunt types in the Norwood procedure for single-ventricle lesions.N Engl J Med. 2010; 362: 1980-1992Crossref PubMed Scopus (682) Google Scholar The causes for these mortalities and morbidities after the Norwood procedure include increased pulmonary vascular resistance, arrhythmia, coronary artery insufficiency, right ventricular (RV) failure, and tricuspid regurgitation (TR).5Ohye R.G. Gomez C.A. Goldberg C.S. et al.Tricuspid valve repair in hypoplastic left heart syndrome.J Thorac Cardiovasc Surg. 2004; 127: 465-472Abstract Full Text Full Text PDF PubMed Scopus (87) Google Scholar Tricuspid valve dysfunction is common in infants born with HLHS managed via univentricular palliation. Approximately one quarter of all survivors will have undergone surgical tricuspid valve procedures within 10 years. 6Elmi M. Hickey E.J. Williams W.G. et al.Long-term tricuspid valve function after Norwood operation.J Thorac Cardiovasc Surg. 2011; 142: 1341-1347Abstract Full Text Full Text PDF PubMed Scopus (41) Google Scholar In fact, new-onset TR may be seen in as many as 10% of children immediately post-Norwood; this finding itself indicates a high risk of subsequent need for tricuspid intervention.6Elmi M. Hickey E.J. Williams W.G. et al.Long-term tricuspid valve function after Norwood operation.J Thorac Cardiovasc Surg. 2011; 142: 1341-1347Abstract Full Text Full Text PDF PubMed Scopus (41) Google Scholar Interstage mortality and death later in childhood are both significant concerns for patients with HLHS undergoing surgical palliation.1Tweddell J.S. Hoffman G.M. Mussatto K.A. et al.Improved survival of patients undergoing palliation of hypoplastic left heart syndrome: lessons learned from 115 consecutive patients.Circulation. 2002; 106: I82-I89PubMed Google Scholar, 2Azakie T. Merklinger S.L. McCrindle B.W. et al.Evolving strategies and improving outcomes of the modified Norwood procedure: a 10-year single-institution experience.Ann Thorac Surg. 2001; 72: 1349-1353Abstract Full Text Full Text PDF PubMed Scopus (207) Google Scholar, 7Ishino K. Stümper O. De Giovanni J.J. et al.The modified Norwood procedure for hypoplastic left heart syndrome: early to intermediate results of 120 patients with particular reference to aortic arch repair.J Thorac Cardiovasc Surg. 1999; 117: 920-930Abstract Full Text Full Text PDF PubMed Scopus (155) Google Scholar Development of significant TR remains an obstacle in improving survival,8Barber G. Helton J.G. Aglira B.A. et al.The significance of tricuspid regurgitation in hypoplastic left-heart syndrome.Am Heart J. 1988; 116: 1563-1567Abstract Full Text PDF PubMed Scopus (89) Google Scholar, 9Bove E.L. Lloyd T.R. Staged reconstruction for hypoplastic left heart syndrome Contemporary results.Ann Surg. 1996; 224: 387-394Crossref PubMed Scopus (218) Google Scholar, 10Chang A.C. Farrell Jr, P.E. Murdison K.A. et al.Hypoplastic left heart syndrome: hemodynamic and angiographic assessment after initial reconstructive surgery and relevance to modified Fontan procedure.J Am Coll Cardiol. 1991; 17: 1143-1149Abstract Full Text PDF PubMed Scopus (78) Google Scholar, 11Mosca R.S. Bove E.L. Tricuspid valvuloplasty in hypoplastic left heart syndrome.Semin Thorac Cardiovasc Surg Pediatr Card Surg Annu. 1999; 2: 21-34PubMed Google Scholar and likely compromised functional health after univentricular palliation of HLHS. The natural and surgically modified survivals of the single-ventricle patient with significant tricuspid valve insufficiency have been consistently poorer than that in the single-ventricle patient with a competent tricuspid valve. Barber et al,8Barber G. Helton J.G. Aglira B.A. et al.The significance of tricuspid regurgitation in hypoplastic left-heart syndrome.Am Heart J. 1988; 116: 1563-1567Abstract Full Text PDF PubMed Scopus (89) Google Scholar who reported survival of patients with HLHS undergoing Norwood procedure between 1984 and 1987. They showed a significantly worse survival in patients with significant tricuspid valve insufficiency (survival, 55% vs 35% at 1 year after Norwood procedure). Because no intervention was performed on the tricuspid valve in this population, this study provides a nice 'natural history' evaluation of the effect of tricuspid valve insufficiency on survival. Ohye et al5Ohye R.G. Gomez C.A. Goldberg C.S. et al.Tricuspid valve repair in hypoplastic left heart syndrome.J Thorac Cardiovasc Surg. 2004; 127: 465-472Abstract Full Text Full Text PDF PubMed Scopus (87) Google Scholar reported a series of 28 patients with HLHS who underwent tricuspid valve repair after Norwood procedure that essentially suggested that postoperative RV function and residual tricuspid valve insufficiency are the major determinants for survival. Patients who had successful tricuspid valve repair (residual insufficiency, grade 0 to 2) with preserved RV function had the best survival (survival rate without transplant, 88%). On the other hand, there was 80% mortality in patients with early or late RV dysfunction, regardless of the result of tricuspid valve repair. The complexity of surgical repair of the tricuspid valve, as well as the timing of repair, appeared to have some bearings in terms of survival and subsequent valvar competency. Recently, Elmi and associates6Elmi M. Hickey E.J. Williams W.G. et al.Long-term tricuspid valve function after Norwood operation.J Thorac Cardiovasc Surg. 2011; 142: 1341-1347Abstract Full Text Full Text PDF PubMed Scopus (41) Google Scholar reported that tricuspid valve surgery was necessary in up to 25% of survivors after single-ventricle palliation. This study also showed that tricuspid valve intervention was successful in restoring functional natural history to that of the remainder of the cohort. Furthermore, tricuspid valve intervention did not compromise survival (82% ± 2%, 5 years after tricuspid valve intervention), and RV function was not worse in patients requiring tricuspid valve intervention. Mechanisms of development of tricuspid valve insufficiency in the single-ventricle physiology are complex and multifactorial. Suboptimal afterload, such as important aortic arch reconstruction after stage 1 repair, must be excluded. The three other major factors that trigger the development of significant TR are chronic volume overload, structural tricuspid valve abnormalities, and myocardial damage/ischemia. Because the tricuspid valve is designed to sustain the competency in the low-resistance pulmonary circulation, it is believed to be more susceptible to pressure or volume overload. In patients who had more than moderate pulmonary hypertension (pulmonary artery pressure, 50 to 69 mmHg) in the setting of a biventricular physiology, approximately one third of patients had more than moderate tricuspid valve insufficiency, with half having competent or mildly insufficient tricuspid valves.12Mutlak D. Aronson D. Lessick J. et al.Functional tricuspid regurgitation in patients with pulmonary hypertension: is pulmonary artery pressure the only determinant of regurgitation severity?.Chest. 2009; 135: 115-121Crossref PubMed Scopus (152) Google Scholar During staged Fontan strategy, patients with functionally single ventricles may be exposed to high pulmonary blood flow with increased ventricular volume and workload. Chronic volume overload causes progressive ventricular dilatation,13Kuroda O. Sano T. Matsuda H. et al.Analysis of the effects of the Blalock-Taussig shunt on ventricular function and the prognosis in patients with single ventricle.Circulation. 1987; 76: III24-III28PubMed Google Scholar annular dilation, and a 'functional' leaflet tethering, leading to malcoaptation of the leaflets with increasing TR. The majority of the patients with a single-ventricle physiology who undergo a neonatal palliation with a systemic-to-pulmonary shunt (Blalock-Taussig shunt or Norwood type procedure) will result in a shunt-dependent in-parallel circulation. The systemic single ventricle is exposed to considerable volume overload until the time of stage II palliation, where a cavopulmonary shunt-type operation makes circulation in-series, minimizing volume overload.14Berman N.B. Kimball T.R. Systemic ventricular size and performance before and after bidirectional cavopulmonary anastomosis.J Pediatr. 1993; 122: S63-S67Abstract Full Text PDF PubMed Scopus (39) Google Scholar In a recently published study reporting impact of shunt type on RV and tricuspid valve function, Blalock-Taussig shunt patients were shown to have more TR and needed more tricuspid valvuloplasties.15Bautista-Hernandez V. Scheurer M. Thiagarajan R. et al.Right ventricle and tricuspid valve function at midterm after the Fontan operation for hypoplastic left heart syndrome: impact of shunt type.Pediatr Cardiol. 2011; 32: 160-166Crossref PubMed Scopus (16) Google Scholar Significant (at least moderate to severe) regurgitation is more frequently observed when the systemic atrioventricular valve is either morphologically common or tricuspid.16Mahle W.T. Cohen M.S. Spray T.L. et al.Atrioventricular valve regurgitation in patients with single ventricle: impact of the bidirectional cavopulmonary anastomosis.Ann Thorac Surg. 2001; 72: 831-835Abstract Full Text Full Text PDF PubMed Scopus (87) Google Scholar Not infrequently, intrinsic abnormal valve architecture with dysplastic leaflets, tethered, or prolapsed leaflets with reduced coaptation can also contribute to significant valve regurgitation. Stamm et al17Stamm C. Anderson R.H. Ho S.Y. The morphologically tricuspid valve in hypoplastic left heart syndrome.Eur J Cardiothorac Surg. 1997; 12: 587-592Crossref PubMed Scopus (63) Google Scholar examined 82 specimens with HLHS in a view of morphologic tricuspid valve as a systemic atrioventricular valve. One third of the specimens had moderate or severe tricuspid valvular dysplasia, which was particularly common in the presence of a patent mitral valve. Other abnormalities included bileaflet or, rarely, quadraleaflet tricuspid valve (12%), accessory orifices, prolapse of the anterior leaflet, and, rarely, Ebstein's anomaly. In other words, this autopsy series clearly shows is that not all tricuspid valve insufficiency in single-ventricle physiology is 'functional' in nature. After an infarction or ischemic damage, the human heart undergoes a series of structural changes that are governed by cellular and molecular mechanisms in a pathologic metamorphosis termed 'remodeling.'18Gajarsa J.J. Kloner R.A. Left ventricular remodeling in the post-infarction heart: a review of cellular, molecular mechanisms, and therapeutic modalities.Heart Fail Rev. 2011; 16: 13-21Crossref PubMed Scopus (193) Google Scholar Remodeling is the result of local as well as global ventricular dysfunction leading to progressive ventricular dilatation and geometrical distortion of the ventricle, as well as subvalvular apparatus, including papillary muscle. This alteration in the geometrical relationship between the ventricle and valve apparatus generates a restricted leaflet motion that, coupled with annular dilatation, leads to subsequent valvular regurgitation.19Otsuji Y. Handschumacher M.D. Liel-Cohen N. et al.Mechanism of ischemic mitral regurgitation with segmental left ventricular dysfunction: three-dimensional echocardiographic studies in models of acute and chronic progressive regurgitation.J Am Coll Cardiol. 2001; 37: 641-648Abstract Full Text Full Text PDF PubMed Scopus (273) Google Scholar Ventricular dysfunction may result secondary to circulatory arrest, ischemia-reperfusion injury, hemodilution, inflammatory response, high post-bypass systemic vascular resistance, and intrinsic vulnerability of neonatal systemic RV.20Allen B.S. Pediatric myocardial protection: a cardioplegic strategy is the "solution".Semin Thorac Cardiovasc Surg Pediatr Card Surg Annu. 2004; 7: 141-154Abstract Full Text Full Text PDF PubMed Scopus (31) Google Scholar First-stage palliation of HLHS with either systemic-to-pulmonary artery shunt or right-ventricle-to-pulmonary artery shunt also affects global and regional ventricular function, with the potential to predispose to ventricular remodeling and valvular regurgitation. There is evidence to suggest that placement of a systemic-to-pulmonary shunt decreases ejection fraction of the systemic ventricle.13Kuroda O. Sano T. Matsuda H. et al.Analysis of the effects of the Blalock-Taussig shunt on ventricular function and the prognosis in patients with single ventricle.Circulation. 1987; 76: III24-III28PubMed Google Scholar In addition, a diastolic run-off through the systemic-to-pulmonary shunt may reduce effective coronary artery blood flow, thereby potentially leading to ventricular dysfunction.21Raja S.G. Right ventricle to pulmonary artery shunt modification of the Norwood procedure.Expert Rev Cardiovasc Ther. 2010; 8: 675-684Crossref PubMed Scopus (6) Google Scholar Similarly, concerns persist regarding the deleterious effects of ventriculotomy for right-ventricle-to-pulmonary artery shunt on ventricular performance and remodeling.22Raja S.G. Atamanyuk I. Kostolny M. et al.In hypoplastic left heart patients is Sano shunt compared with modified Blalock-Taussig shunt associated with deleterious effects on ventricular performance?.Interact Cardiovasc Thorac Surg. 2010; 10: 620-623Crossref PubMed Scopus (19) Google Scholar Elmi et al,6Elmi M. Hickey E.J. Williams W.G. et al.Long-term tricuspid valve function after Norwood operation.J Thorac Cardiovasc Surg. 2011; 142: 1341-1347Abstract Full Text Full Text PDF PubMed Scopus (41) Google Scholar in a recently published study, have analyzed the predictors of tricuspid valve intervention in the setting of TR in HLHS. They reported the presence of mitral atresia and longer myocardial ischemia during Norwood operation as incremental risk factors (at the time of diagnosis) for tricuspid valve intervention. In mitral atresia (similar to most cases of aortic atresia), left ventricular flow is completely absent. All systemic cardiac output must necessarily be generated via the RV (by contrast, in univentricular repair of critical aortic stenosis, a small proportion of systemic cardiac output will be via the left heart). When left ventricular flow is zero, presumably the right cardiac structures are therefore operating under maximum hemodynamic stress with the potential for ventricular dilatation and subsequent TR. Longer myocardial ischemic time during the Norwood operation results in subendocardial ischemic injury.6Elmi M. Hickey E.J. Williams W.G. et al.Long-term tricuspid valve function after Norwood operation.J Thorac Cardiovasc Surg. 2011; 142: 1341-1347Abstract Full Text Full Text PDF PubMed Scopus (41) Google Scholar Subendocardial ischemic injury may lead to papillary muscle dysfunction or late remodeling of RV geometry. Alternatively, it is possible that longer myocardial ischemic time is a surrogate for more complex cardiac morphology and an indirect risk factor for valvular regurgitation. The accurate assessment of the regurgitant tricuspid valve is an essential prerequisite for sound decision-making and durable repair. Preoperative anatomic and functional evaluation of the tricuspid valve can be achieved by using color Doppler echocardiography and, recently, 3-dimensional echocardiography. It may be useful to classify the valves as requiring simple (annuloplasty) or complex (anteroseptal, posterior, bileaflet, or commissural) repairs, and such preoperative categorization may improve the repair rate as well as subsequent reporting in the literature. Magnetic resonance imaging can also provide important information regarding the presence of recurrent arch obstruction, the status of the pulmonary vasculature, quantification of RV systolic function, and the tricuspid valve regurgitant fraction. At present, there are no clear-cut guidelines for the timing of repair. However, significant TR at first presentation remains a very challenging problem with a very poor long-term prognosis. These small infants may have intrinsic valve abnormalities and the very fragile valve tissue would render successful repair notoriously difficult. Surgical abstention or transplantation rather than a Norwood procedure may be advocated. With the key provision that the aortic arch repair is satisfactory post Norwood procedure, evaluation of available retrospective studies on the subject suggests that the tricuspid valve needs to be repaired when the TR is significant (at least moderate to severe). Tricuspid valve repair can be performed as an isolated procedure, or commonly in conjunction with bidirectional cavopulmonary anastomosis.5Ohye R.G. Gomez C.A. Goldberg C.S. et al.Tricuspid valve repair in hypoplastic left heart syndrome.J Thorac Cardiovasc Surg. 2004; 127: 465-472Abstract Full Text Full Text PDF PubMed Scopus (87) Google Scholar On the other hand, there is evidence to suggest that moderate-to-severe TR improves in some patients after bidirectional cavopulmonary anastomosis. Therefore, valvuloplasty would not be justified in all patients, in the hope that with the current approach of early staged management of Fontan circulation, the decreased ventricular volume is accompanied by a reduction in the tricuspid annulus dimension and may result in improved tricuspid valve function.16Mahle W.T. Cohen M.S. Spray T.L. et al.Atrioventricular valve regurgitation in patients with single ventricle: impact of the bidirectional cavopulmonary anastomosis.Ann Thorac Surg. 2001; 72: 831-835Abstract Full Text Full Text PDF PubMed Scopus (87) Google Scholar, 23Michlefelder E.C. Kimball T.R. Beekman R.H. Does the superior cavopulmonary anastomosis impact the rate of tricuspid annular dilation in hypoplastic left heart syndrome.J Am Coll Cardiol. 2001; 37 ([abstract]): 471AAbstract Full Text PDF Google Scholar The timing and the threshold for inspection and repair of a significantly regurgitant tricuspid valve can also be influenced by institutional approaches, particularly where hemiFontan and lateral tunnel Fontan are routinely undertaken. These surgical strategies would involve aortic cross clamping and a right atriotomy with good access to the tricuspid valve. In general, it is intuitively sensible to undertake concomitant tricuspid valve repair at the time of a necessary surgical stage. However, some children will require intervention on the regurgitant tricuspid valve outside the typical univentricular surgical paradigm. This subset of children is especially important because they presumably reflect tricuspid valve dysfunction that mandated isolated tricuspid intervention on the grounds of severity or late onset. The majority of these children have mitral atresia that is recognized as the most important and reliable determinant of tricuspid valve intervention outside the usual univentricular operative paradigm.6Elmi M. Hickey E.J. Williams W.G. et al.Long-term tricuspid valve function after Norwood operation.J Thorac Cardiovasc Surg. 2011; 142: 1341-1347Abstract Full Text Full Text PDF PubMed Scopus (41) Google Scholar Finally, a small but important number of children will require tricuspid valve repair well beyond completion of Fontan physiology. These children have tricuspid dysfunction as a consequence of a failing systemic RV, perhaps because of annular dilatation. However, it is important to mention that tricuspid repair or replacement in the context of severe RV dysfunction often does not lead to ventricular recovery, emphasizing the need for intervention before severe RV dysfunction sets in.24Carrel T. Pfammatter J.P. Complete transposition of the great arteries: surgical concepts for patients with systemic right ventricular failure following intraatrial repair.Thorac Cardiovasc Surg. 2000; 48: 224-227Crossref PubMed Scopus (43) Google Scholar A variety of techniques, well known to many experienced cardiac surgeons, have been used to repair tricuspid valves in the setting of single ventricle, including circular/partial annuloplasty, repair of cleft leaflets, edge-to-edge repair of superior and septal leaflets to primary commissural closure, and, less frequently, mobilization of the septal leaflet and chordal shortening.5Ohye R.G. Gomez C.A. Goldberg C.S. et al.Tricuspid valve repair in hypoplastic left heart syndrome.J Thorac Cardiovasc Surg. 2004; 127: 465-472Abstract Full Text Full Text PDF PubMed Scopus (87) Google Scholar, 16Mahle W.T. Cohen M.S. Spray T.L. et al.Atrioventricular valve regurgitation in patients with single ventricle: impact of the bidirectional cavopulmonary anastomosis.Ann Thorac Surg. 2001; 72: 831-835Abstract Full Text Full Text PDF PubMed Scopus (87) Google Scholar, 25Ando M. Takahashi Y. Edge-to-edge repair of common atrioventricular or tricuspid valve in patients with functionally single ventricle.Ann Thorac Surg. 2007; 84: 1571-1576Abstract Full Text Full Text PDF PubMed Scopus (16) Google Scholar Surgical techniques must be individualized to the patient's valve pathology. Additional lesions, such as residual or recurrent aortic arch obstruction, can increase TR and RV dysfunction, and must be dealt with by surgical or catheter interventions before or at the time of TV repair. Nevertheless, tricuspid valve repair can be accomplished in this challenging and diverse patient population with good results. This section provides an overview of the various repair techniques. The De Vega tricuspid annuloplasty safely provides excellent relief of TR.26Kanter K.R. Doelling N.R. Fyfe D.A. et al.De Vega tricuspid annuloplasty for tricuspid regurgitation in children.Ann Thorac Surg. 2001; 72: 1344-1348Abstract Full Text Full Text PDF PubMed Scopus (27) Google Scholar It is a useful technique to be considered in cases of TR secondary to annular dilatation. The De Vega tricuspid annuloplasty has the advantages of simplicity and effectiveness.27Raja S.G. Dreyfus G.D. Surgery for functional tricuspid regurgitation: current techniques, outcomes and emerging concepts.Expert Rev Cardiovasc Ther. 2009; 7: 73-84Crossref PubMed Scopus (36) Google Scholar It is performed by using a pledgetted annuloplasty suture of 4/0 polypropylene that is started at the anteroseptal commissure and sewn intermittently to the junction of the annulus and the RV along the anterior and posterior leaflets until just past the posteroseptal commissure (Fig. 1A). Another pledget is placed and the suturing is reversed along the posterior and anterior leaflets 1 to 2 mm from the first row, alternating the suture technique (ie, taking bites on the second row where the suture is out on the first row and vice versa) until the original pledget at the anteroseptal commissure is reached (Fig 1B). The suture is tied down snugly over a Hegar dilator calibrated to 2 to 3 mm larger than the predicted appropriate pulmonary annulus size derived from published nomograms.28Kanter K.R. Forbess J.M. Fyfe D.A. et al.De Vega tricuspid annuloplasty for systemic tricuspid regurgitation in children with univentricular physiology.J Heart Valve Dis. 2004; 13: 86-90PubMed Google Scholar Kanter et al28Kanter K.R. Forbess J.M. Fyfe D.A. et al.De Vega tricuspid annuloplasty for systemic tricuspid regurgitation in children with univentricular physiology.J Heart Valve Dis. 2004; 13: 86-90PubMed Google Scholar have reported encouraging results for De Vaga annuloplasty in 12twelve children (median age, 2.2 years; range, 6 months to 17 years) with single-ventricle physiology who had moderate or severe systemic TR. They underwent a De Vega tricuspid annuloplasty during a bidirectional Glenn anastomosis (n = 3), Fontan procedure (n = 8), or aortic valve replacement late after a Fontan procedure (n = 1). Nine patients (75%) had prior Norwood palliation for HLHS. Four patients had simultaneous repair of an abnormal tricuspid valve in addition to the De Vega procedure. There were no deaths during a mean follow-up of 2.0 ± 1.4 years (range, 6 months to 5.1 years). One child required pacemaker implantation early after operation, and one child with a Glenn anastomosis underwent cardiac transplantation 21 months postoperatively. In the remaining 11 patients, the most recent echocardiogram showed mild or no TR in eight children, mild-to-moderate TR in one child, and moderate TR in two children. No child had symptomatic TR (including the two with moderate TR), significant tricuspid stenosis, or late pacemaker implantation. The durability of the De Vega annuloplasty in children and fixing the size of the tricuspid valve annulus in a growing child are two major concerns that have prevented universal use of this technique in children in general, and in patients with HLHS in particular. As an extension of the De Vaga annuloplasty concept, Imai and associates29Imai Y. Takanashi Y. Hoshino S. et al.Modified Fontan procedure in ninety-nine cases of atrioventricular valve regurgitation.J Thorac Cardiovasc Surg. 1997; 113: 262-268Abstract Full Text Full Text PDF PubMed Scopus (60) Google Scholar described a circular annuloplasty for various types of atrioventricular valve morphology. A 2-0 or 3-0 polytetrafluoroethylene suture is passed through the annulus circumferentially, and the full circular purse-string suture is tied over a 22 or 24 mm Hegar dilator. The suture is placed on the leaflet itself at the area of conduction system. In this series of 99 patients with atrioventricular valve regurgitation undergoing modified Fontan procedure, in 49 cases with higher than grade 2 regurgitation before operation there was a significant decrease to 0.4 ± 0.49 (P < .0001) after operation in short-term survivors. Currently, long-term follow-up is not available for this technique. Partial annuloplasty (Fig. 2) and commissuroplasty (Fig. 3) are commonly used techniques for functional central regurgitation because of annular dilatation and/or localized prolapse of the leaflet(s). Usually, 5-0 polypropylene or 4-0 polyester sutures are used to locally reduce the annulus size along the commissure(s), where the regurgitant jet mainly comes from. This maneuver is essentially a functional commissuroplasty on the corresponding commissure.Figure 3Partial commissure closure
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