[Hybrid procedures in congenital heart disease]

Cardiology Hybrid Procedures in Congenital Heart Disease a report by S t e f a n o D i B e r n a r d o , 1 M i c h e l H u r n i 2 and M a r i e - H é l è n e P e r e z 3 1. Paediatric Catheterisation Laboratory, Department of Paediatrics; 2. Department of Cardiovascular Surgery; 3. Intensive Care Unit, Department of Paediatrics, University Hospital and University of Lausanne Surgery and interventional cardiology have developed greatly during the arteries. The second step, Norwood stage II, is a bidirectional Glenn last decades. For any congenital heart disease a surgical procedure is anastomosis. The third step is the completion of a Fontan circulation, with possible to obtain complete correction or acceptable palliation. Progress in a connection between inferior vena cava and pulmonary arteries. interventional cardiology opens up new directions for the treatment of simple heart defects. Today many simple lesions are suitable for correction HLHS is a typical congenital cardiac malformation with the first surgical in the catheterisation laboratory. Since the beginning of this century long- palliation occurring in the first days after birth, in which high surgical term follow-up studies and developmental surveys have been published.1-3 mortality and high long-term morbidity have been reported. Some authors Paediatric patients with congenital heart disease, particularly those who have demonstrated a striking association for these infants between need an intervention in the perinatal period or repeated surgeries, duration of deep hypothermic circulatory arrest performed during this demonstrate different kinds of disability at school age. Although surgical procedure and developmental outcome at school age.1 cardiopulmonary bypass is a huge advance, it also has detrimental effects. In an attempt to change the traditional surgical strategy, hybrid therapy Confronted with these observations, new strategies have been developed combines stent implantation in the ductus arteriosus by the interventional to shorten cardiopulmonary bypass or to avoid particularly risky surgical cardiologist and a surgical band for both pulmonary arteries, in order to approaches. These new strategies are called hybrid procedures because maintain systemic perfusion and restrict pulmonary blood flow to the they emerge from the collaborative efforts of cardiac surgeons and lungs. Usually, this procedure is completed with a unique step through a interventional cardiologists in an approach to managing congenital heart median sternotomy without the need for cardiopulmonary bypass.6,7 A disease. The idea is to develop therapies that offer the advantages of few months later, with a larger infant, a comprehensive stage I and II surgery and interventional techniques in the same setting.4,5 Norwood is performed. The main advantage of this technique is to postpone the Norwood I procedure to a later age, allowing a decreasing Hybrid therapy is not a simple first step. It is a change in approach for global risk of this surgical procedure in the neonatal period and avoiding surgeons and cardiologists. Both have to admit that joining the two deep hypothermic circulatory arrest. Reconstruction of the aortic arch is techniques would possibly allow better immediate and long-term results. then carried out in a larger infant, with a probable decreased risk of brain It also means that cardiologists can enter the operating theatre for other insult than in the neonatal period. The second advantage is to reduce the reasons than only to look at the transoesophageal echocardiography number of interventions with cardiopulmonary bypass. (TEE) and that surgeons can enter the catheterisation laboratory not only for emergency purposes. In other words, surgeons and cardiologists have As for any new surgical or interventional procedure there is a learning curve. to discuss and collaborate in a positive fashion. Initial problems have been identified and can be overcome. For example, tightening of the pulmonary bands (too tight or too loose) and stenting of Indications for hybrid therapy are expanding, the most frequent being the ductus arteriosus when aortic coarctation is present have been intraoperative stenting, perventricular ventricular septal defect (VSD) addressed as a result of published expertise from leading centres.8 Although closure, occlusion of vascular structures during surgical repair and long-term follow-up data are still not known, short- and medium-term percutaneous palliation for single ventricle physiology (such as follow-up is impressive and comparable to surgical results.7,9–12 hypoplastic left heart syndrome [HLHS]). Ideally, these interventions are carried out in a hybrid suite where operating room and catheterisation Avoiding cardiopulmonary bypass with hybrid therapy does not mean laboratory facilities are brought together. that these patients are less prone to interstage problems and mortality. Indications, Techniques and Experience Hypoplastic Left Heart Syndrome HLHS associates hypoplastic left ventricle (unsuitable for systemic perfusion), aortic valve stenosis and hypoplasia of the ascending aorta. Since the 1980s a three-step surgical palliation can be proposed for these infants. The first step is Norwood stage I, whereby reconstruction of the aortic arch with anastomosis to the pulmonary trunk is performed. At the same time pulmonary blood flow is provided with a modified Blalock- Stefano Di Bernardo is a Paediatric Cardiologist in the Department of Paediatrics of the University Hospital at the University of Lausanne, Switzerland, where he has been Head of the Congenital Catheterisation Laboratory since 2003 and in charge of the development of a hybrid therapy programme for congenital heart disease. Dr Di Bernardo is a member of the Swiss Society of Paediatric Cardiology, the Swiss Society of Cardiology, the Association for European Paediatric Cardiology (AEPC) and the Working Group on Interventional Cardiology of the AEPC. Following his paediatrics training at the University Hospital of Lausanne, he undertook further training in paediatric cardiology and particularly in interventional cardiology in the Children’s Hospital of Zurich. E: stefano.di-bernardo@chuv.ci Taussig shunt or a shunt between the right ventricle and pulmonary © TOUCH BRIEFINGS 2008 11 Cardiology These infants remain high-risk patients. Strict ambulatory follow-up is situations. Usually, the procedure is monitored by fluoroscopy and mandatory to anticipate potential complications. For example, insufficient performed at the time of another planned surgery, such as a conduit stenting of the ductus arteriosus, obstruction of one or even both change. According to the type of lesions, the surgeon either provides pulmonary arteries and dysfunction of the right ventricle in systemic access to the lesion (through the main artery purse ring suture, for position are potential acute problems that can occur at any time between example) or the main pulmonary is opened and direct stenting of the first and second intervention.11 pulmonary arteries achieved under direct visualisation.12,17-19 Isolated Ventricular Septal Defect or in Association with In these complex patients with different levels of right ventricular outflow Other Congenital Malformations tract obstruction, any effort to reduce the number of interventions and VSD is one of the most frequent congenital heart diseases. It can be their associated morbidity is of great help. In addition, improving in fewer isolate, multiple or associated with more complex congenital stages the obstruction and so decreasing right ventricular pressure will malformation such as double outlet right ventricle or transposition of the hopefully contribute to improved long-term outcome. great arteries. Most of the VSDs are localised in the perimembranous area of the interventricular septum, and only 20% are in the muscular part. Occlusions of Vascular or Surgical Structures Specific devices have been developed for interventional closure of During Surgery perimembranous and muscular VSDs. Interventional closure of muscular In some particular settings, pulmonary perfusion is dependent on VSDs is one of the most challenging percutaneous interventions because abnormal vascular structure or surgical shunts. Surgical ligation of these of high anatomical variability, different thickness of the muscular septum alternative ways of pulmonary flow could be difficult and time and the presence of trabeculations on the right ventricular side. In consuming for the surgeon. A stepped approach with closure of devices addition, infants with symptomatic VSD demonstrate signs of congestive of these structures followed by surgery is almost impossible without a heart failure and failure to thrive and are potentially too unstable for a significant decrease of arterial saturation, leading to haemodynamic long catheterisation procedure. Thus, most of them are not suitable for instability of the patient. percutaneous closure. On the other hand, surgical muscular VSD closure could be difficult for the same anatomical reason (localisation of the VSD With a hybrid procedure, occlusion of vascular or surgical structures is in the muscular septum and visibility of this area in an arrested heart). feasible during surgery. Intervention is performed under fluoroscopy or TEE guidance. According to anatomical location, size and length of the To overcome these problems and find a better strategy, a hybrid therapy shunt, the cardiologist will choose the most suitable type of device (coils has been developed. The procedure is performed under TEE guidance and or vascular occluder) to be used for the intervention. Once obstruction of after median sternotomy or mini-sternotomy. A purse ring suture is placed the shunt is obtained, cardiopulmonary bypass is initiated and the on the right ventricular free wall opposite to the VSD, allowing the VSD to surgical procedure performed. be crossed directly with a needle. An appropriately sized sheath is then advanced through the VSD. Before the device is released the location of In these cases, collaborative planning between surgical and cardiological the device is checked with TEE. The same procedure could be performed, teams is mandatory before surgery in order to obtain the best result for for example, in the case of repair of transposition of great arteries with the patient. Again, the main goal of this approach is to reduce duration VSD or repair of a double outlet ventricle. The advantages are the of surgery and cardiopulmonary bypass. shortened time of cardiopulmonary bypass and simplification of an already complex surgery. In cases of multiple muscular VSD (so-called Swiss cheese Issues, Debates and Conflicts in Hybrid Procedures presentation) the procedure can be repeated, allowing every significant Increasing numbers of publications have addressed the problems raised by defect to be closed.12-16 hybrid procedures. The debate is particularly exacerbated when considering HLHS or similar pathologies.20,21 Based on mortality, length of Overall results are excellent and the avoidance of cardiopulmonary bypass stay in intensive care unit and hospital, and short- and medium-term for these sick infants is a great advance. survival, many publications have focused on whether hybrid therapy offers the same results as a standard surgical approach. In these articles, hybrid Intraoperative Stenting of Pulmonary Arteries therapy is offered, most of the time, to patients facing high-risk surgery, Congenital heart disease with right ventricular obstruction is frequently and standard surgery is offered to those facing simpler surgeries.22,23 Most associated with stenotic or hypoplastic peripheral pulmonary arterial of the published experience comes from leading centres where a high branches. Recurrent stenosis of the pulmonary arteries is usual and amount of surgery is performed. Their experience, however, may not impairs normalisation of right ventricular pressure. Redo surgery has the reflect that of other centres worldwide. Indeed, depending on the surgical disadvantage that dissection and recognition of structures are made team and intensive care unit experience, differences in mortality or other more difficult. On the other hand, percutaneous intervention is possible short-term issue can vary dramatically. In our opinion the main issue is not with balloon angioplasty (standard balloon, high-pressure balloon or whether hybrid therapy is performed as well as a standard surgical cutting balloon) or with stent deployment. The main issues in these approach but whether changing our surgical strategy for a less aggressive cases are either vascular access or reaching the lesion in a satisfactory strategy will change long-term neuro-developmental outcomes. fashion for the intervention. Tortuous pulmonary branches and cardiac conduit between right ventricle and pulmonary artery are some of the Conclusion obstacles for cardiologists. Congenital heart disease represents a large panel of different diseases, with different problematic clinical and follow-up outcomes. In this Again, hybrid therapy offers possibilities to overcome these challenging 12 area, the development of hybrid procedures is a promising tool. EUROPEAN PAEDIATRICS Hybrid Procedures in Congenital Heart Disease This new way of thinking allows new strategies of palliation or creating or inventing new procedure strategies. This will be acceptable correction to be offered for simple and complex congenital heart only if these new strategies obtain results as good as the previous ones diseases. For some rare cases it may be a unique way of allowing an and demonstrate a beneficial effect on the long-term follow-up of acceptable result for the patient. Although many of these types of patients. This question is still unanswered at this point. intervention are already standardised, many will never be. Some cases are so unusual that the applied strategy would never be comparable Finally, in our opinion, hybrid therapy is an alternative approach for with any ‘gold standard’ surgery. The main issue of implementing a dealing with congenital heart disease and a great opportunity for surgical hybrid therapy programme is a trend in avoiding surgical insults to infants and medical teams to think and plan together to overcome the and children with congenital heart disease. This has been carried out by limitations of the usual surgical or interventional procedures. ■ 1. 2. 3. 4. 5. 6. 7. 8. Mahle WT, Clancy RR, Moss EM, et al., Neurodevelopmental outcome and lifestyle assessment in school-aged and adolescent children with hypoplastic left heart syndrome, Pediatrics, 2000;105(5):1082–9. Sharma R, Choudhary SK, Mohan MR, et al., Neurological evaluation and intelligence testing in the child with operated congenital heart disease, Ann Thorac Surg, 2000;70(2):575–81. Mahle WT, Neurologic and cognitive outcomes in children with congenital heart disease, Curr Opin Pediatr, 2001;13(5):482–6. Hjortdal VE, Redington AN, de Leval MR, Tsang VT, Hybrid approaches to complex congenital cardiac surgery, Eur J Cardiothorac Surg, 2002;22(6):885–90. Hijazi ZM, Intraoperative intervention (hybrid surgery) and intervention in the immediate perioperative period, Catheter Cardiovasc Interv, 2003;60(1):99–100. Akintuerk H, Michel-Behnke I, Valeske K, et al., Stenting of the arterial duct and banding of the pulmonary arteries: basis for combined Norwood stage I and II repair in hypoplastic left heart, Circulation, 2002;105(9):1099–1103. Bacha EA, Daves S, Hardin J, et al., Single-ventricle palliation for high-risk neonates: the emergence of an alternative hybrid stage I strategy, J Thorac Cardiovasc Surg, 2006;131(1):163–171, e162. Galantowicz M, Cheatham JP, Lessons learned from the development of a new hybrid strategy for the management of hypoplastic left heart syndrome, Pediatr Cardiol, 9. 10. 11. 12. 13. 14. 15. 16. 2005;26(2):190–99. Alsoufi B, Bennetts J, Verma S, Caldarone CA, New developments in the treatment of hypoplastic left heart syndrome, Pediatrics, 2007;119(1):109–17. Caldarone CA, Benson L, Holtby H, et al., Initial experience with hybrid palliation for neonates with single-ventricle physiology, Ann Thorac Surg, 2007;84(4):1294–1300. Galantowicz M, Cheatham JP, Phillips A, et al., Hybrid approach for hypoplastic left heart syndrome: intermediate results after the learning curve, Ann Thorac Surg, 2008;85(6):2063–70, discussion 2070–61. Bacha EA, Hijazi ZM, Cao QL, et al., Hybrid pediatric cardiac surgery, Pediatr Cardiol, 2005;26(4):315–22. Amin Z, Cao QL, Hijazi ZM, Closure of muscular ventricular septal defects: transcatheter and hybrid techniques, Catheter Cardiovasc Interv, 2008;72(1):102–11. Diab KA, Hijazi ZM, Cao QL, Bacha EA, A truly hybrid approach to perventricular closure of multiple muscular ventricular septal defects, J Thorac Cardiovasc Surg, 2005;130(3):892–3. Di Bernardo S, Sekarski N, Mivelaz Y, et al., Hybrid procedures in congenital heart disease, Rev Med Suisse, 2008;4(150):788–92. Bacha EA, Cao Q-L, Starr JP, et al., Perventricular device closure of muscular ventricular septal defects on the beating heart: technique and results, Journal of Thoracic and Cardiovascular Surgery, 2003;126(6):1718–23. 17. Nykanen DG, Zahn EM, Transcatheter techniques in the management of perioperative vascular obstruction, Catheter Cardiovasc Interv, 2005;66(4):573–9. 18. Bokenkamp R, Blom NA, De Wolf D, et al., Intraoperative stenting of pulmonary arteries, Eur J Cardio-Thoracic Surg, 2005;27(4):544–7. 19. Rosales AM, Lock JE, Perry SB, Geggel RL, Interventional catheterization management of perioperative peripheral pulmonary stenosis: Balloon angioplasty or endovascular stenting, Catheterization and Cardiovascular Interventions, 2002;56(2):272–7. 20. Pizarro C, Derby CD, Baffa JM, et al., Improving the outcome of high-risk neonates with hypoplastic left heart syndrome: hybrid procedure or conventional surgical palliation?, Eur J Cardiothorac Surg, 2008;33(4):613–18. 21. Pigula FA, Vida V, Del Nido P, Bacha E, Contemporary results and current strategies in the management of hypoplastic left heart syndrome, Semin Thorac Cardiovasc Surg, 2007;19(3):238–44. 22. Akinturk H, Michel-Behnke I, Valeske K, et al., Hybrid transcatheter-surgical palliation: basis for univentricular or biventricular repair: the Giessen experience, Pediatr Cardiol, 2007;28(2):79–87. 23. Lim DS, Peeler BB, Matherne GP, et al., Risk-stratified approach to hybrid transcatheter-surgical palliation of hypoplastic left heart syndrome, Pediatr Cardiol, 2006;27(1):91–5. Associated Papers New Developments in the Treatment of Hypoplastic Left Heart Syndrome Alsoufi B , Bennetts J , Verma S and Caldarone CA Pediatrics, 2007;119(1):109–17. Improving the Outcome of High-risk Neonates with Hypoplastic Left Heart Syndrome: Hybrid Procedure or Conventional Surgical Palliation? Pizarro C , Derby CD , Baffa JM , Murdison KA and Radtke WA Eur J Cardiothorac Surg, 2008;33(4):613–18. In the current decade, the prognosis of newborns with hypoplastic left heart syndrome, previously considered a uniformly fatal condition, has dramatically improved through refinement of rapidly evolving treatment strategies. These strategies include various modifications of staged surgical reconstruction, orthotopic heart transplantation and hybrid palliation using ductal stenting and bilateral pulmonary artery banding. The variety of treatment approaches are based on different surgical philosophies, and each approach has its unique advantages and disadvantages. Nonetheless, multiple experienced centres have reported improved outcomes in each one of those modalities. The purpose of this review is to outline recent developments in the array of currently available management strategies for neonates with hypoplastic left heart syndrome. Because the vast majority of deaths in this patient population occur within the first months of life, the focus of the review will be evaluation of the impact of these management strategies on survival in the neonatal and infant periods. ■ EUROPEAN PAEDIATRICS Despite significant progress, surgical outcome for high-risk patients with hypoplastic left heart syndrome (HLHS) remains suboptimal. The hybrid palliation lessens the initial operative insult and is expected to improve overall survival; however, the outcome of this management sequence is unknown. In a retrospective review of all high-risk neonates undergoing initial palliation for HLHS either by hybrid or stage I Norwood procedure at a single institution between January 2001 and December 2006, the two strategies were compared using survival after stage II as the end-point for outcome. The cohort included 33 patients (14 hybrid and 19 Norwood). Patients undergoing hybrid palliation had a lower pre-operative pH, higher incidence of organ dysfunction and fewer associated cardiac anomalies. Hospital mortality and interstage mortality was 7/33 (21%) and 6/26 (23%) for the entire cohort, without significant differences between the hybrid and the conventional Norwood strategies. Although the hybrid approach reduces the initial surgical insult, important interstage mortality and ongoing morbidity result in no differences in survival compared with conventional surgical palliation. ■ 13