Bidirectional Glenn Anastomosis Research Articles

Acute Adaptation to Volume Unloading of the Functional Single Ventricle in Children Undergoing Bidirectional Glenn Anastomosis

Objective. Volume unloading of the functional single ventricle after a bidirectional Glenn anastomosis (BDG) prior to 1 year of age leads to improved global ventricular function as measured by the myocardial performance index (MPI), a Doppler-derived measurement of combined systolic and diastolic ventricular function. Systolic function remains unchanged after BDG according to previous studies; however, acute changes in global and diastolic function have not been previously investigated in this cohort. Our objective was to assess the short-term effects of the BDG on global ventricular function in patients with a functional single ventricle. Design. Echocardiograms to obtain MPI, isovolumic contraction time, and isovolumic relaxation time were performed at four time periods: in the operating room, in the operating room prior to BDG, shortly after separation from cardiopulmonary bypass, less than 24 hours postoperatively, and either prior to hospital discharge or at the first clinic follow-up visit. Results. Twenty-six patients were enrolled. There was significant ventricular dysfunction noted shortly after separation from cardiopulmonary bypass, median MPI 0.63 (0.39–0.81), that persisted in the short term postoperatively median MPI 0.50 (0.40–0.63). Isovolumic contraction time did not change, however, isovolumic relaxation time was significantly prolonged following BDG. Conclusion. In the postoperative patient after BDG, systolic function is preserved; however, there is evidence of diastolic and global ventricular dysfunction, at least in the short term.

Repair for acute type A aortic dissection with a long elephant trunk technique

superior cavopulmonary anastomosis was effective and functioned well for 2 years in a patient with huge right ventricular fibroma. As for methodology of superior cavopulmonary anastomosis, bidirectional Glenn anastomosis is preferred to hemi-Fontan procedure because the superior vena cava should be disconnected from the right atrium to guard cavopulmonary anastomosis against tumor extension into the right atrium or right atrial thrombus secondary to right ventricular obstruction. Although surgical excision does not cure the primary disease in metastatic tumors of the heart, palliative resection may be justified for immediate life-threatening danger due to an intracavity space-occupying lesion. Additional bidirectional cavopulmonary anastomosis may provide assurance in long-term pulmonary blood flow in unresectable cardiac metastasis.

Palliative bidirectional Glenn anastomosis for unresectable metastasis in the right ventricle from renal cell carcinoma 16 years after nephrectomy

plantation relative to the transfemoral approach. A patent left internal thoracic artery graft is probably a contraindication to a left axillary approach. The potential to compromise innominate artery flow is a relative contraindication to the right axillary approach. The trans–axillary artery approach offers an additional tool in the new armamentarium for the treatment of aortic stenosis in patients who are candidates for TAVI but who have significant respiratory dysfunction and problematic iliofemoral access precluding the other available techniques. We also believe that it offers some advantages relative to the transfemoral and transapical approaches and is worthy of evaluation in a broader patient population as an alternative access route.

Hybrid Therapy for Hypoplastic Left Heart Syndrome: Reality Check

Pilla et al. [2] are to be congratulated and commended for their honesty and integrity in reporting an unfavorable outcome for the new management strategy of patients with hypoplastic left heart syndrome (HLHS) in their article in this issue of Pediatric Cardiology. What is a hybrid intervention for HLHS? And why do it? Hybrid therapy refers to a collaborative effort between a cardiac surgeon and an interventional cardiologist in managing these patients. Ideally, this is conducted in a hybrid suite. Through a median sternotomy, the surgeon bands the branch pulmonary arteries (left and right), followed by stent implantation in the ductus arteriosus by the interventional cardiologist. In the event the atrial septal communication is restrictive, a stent is placed across the patent foramen ovale either percutaneously or via a peratrial route. This procedure is completed without the need for cardiopulmonary bypass. A few months later, when the infant is larger, a comprehensive stage II (Norwood) with a bidirectional Glenn anastomosis is performed. The obvious advantage of such an approach is the avoidance of a major operation with potential circulatory arrest in the immediate neonatal period with the known risks this carries on the developing brain. In addition, some believe that by postponing a major procedure until the infant is a few months of age, the mortality rate associated with the Norwood operation is reduced. Many centers throughout the world, including experienced centers in the United States, report high surgical mortality for the Norwood operation performed in the immediate neonatal period. In a study by the Congenital Heart Surgeon Society involving 29 centers and 710 neonates from 1994 to 2000, only 54% of patients with HLHS were alive after the Fontan operation [1]. Mortality continues to be high even with modifications of the Norwood, such as the Sano operation, in which a conduit is placed between the right ventricle and the main pulmonary artery. Additional complications may occur in the future after the Sano procedure secondary to right ventriculotomy. This has led some experienced surgeons to abandon this modification. With the newer innovation of the hybrid intervention, many believed that adopting this technique would result in a decreased mortality rate for HLHS. Unfortunately, this was not the case, as shown in the study of Pilla et al., in which there was a high mortality rate for their group of patients. In examining this study, I believe there are potential factors that have contributed to this unwanted outcome, including the small sample size at each site, the different postoperative management strategies for each site, and the lack of infrastructure. Even in centers with good postoperative management and strong infrastructure, the mortality rate of this new hybrid therapy is still high. The group at Nationwide Children’s Hospital in Columbus, Ohio, and our group in Chicago had to change the approach a few times until mortality was decreased with better outcome. It is perhaps advisable for centers wanting to pursue the hybrid approach to management of HLHS to collaborate with centers with well-established track records, such as the team at Columbus, and witness first hand the hybrid procedure and postoperative care that follows. This can be followed by proctoring by experienced cardiologists and surgeons, such as those from Columbus or the group in Giessen, Germany, conducted at the institution seeking to adopt this new methodology. Z. M. Hijazi (&) Rush Center for Congenital & Structural Heart Disease, Rush University Medical Center, Jones 770, 1653 W. Congress Parkway, Chicago, IL 60612, USA e-mail: zhijazi@rush.edu

The Unifocal Bilateral Bidirectional Cavopulmonary Anastomosis

We propose a new surgical technique to manage the presence of bilateral superior venae cavae in single ventricle patients, a recognized risk factor for both bidirectional Glenn anastomosis and Fontan completion. The idea is to convert two small, peripheral and competing bilateral bidirectional cavopulmonary anastomoses into a single, larger, and centrally located cavopulmonary connection. This technique, used in 2 patients, provides a symmetrical distribution of pulmonary blood flow and may, in fact, yield growth of the central pulmonary arteries as well as prevent thrombus formation.

Cardiac magnetic resonance versus routine cardiac catheterization before bidirectional glenn anastomosis in infants with functional single ventricle: a prospective randomized trial.

Routine preoperative catheterization is standard practice in patients with single-ventricle physiology before bidirectional Glenn anastomosis. Because catheterization is invasive and exposes patients to ionizing radiation, cardiac magnetic resonance (CMR) may be a safe and effective alternative. We conducted a prospective, randomized, single-center clinical trial comparing catheterization with CMR in patients considered for bidirectional Glenn operation from February 2003 to June 2006. End points were frequency of adverse events of the preoperative evaluation and a composite score of clinically successful surgery. Of 92 eligible patients, 82 were enrolled on the basis of screening echocardiogram, fulfillment of inclusion criteria, and informed consent. Patients were randomized to catheterization (n=41) or CMR (n=41). There were no baseline differences between groups. Four treatment crossovers occurred, 3 to catheterization and 1 to CMR. Catheter interventions were performed in 17 patients (41%). Catheterization resulted in more minor adverse events (78% versus 5%; P<0.001), longer preoperative hospital stays (median, 2 versus 1 day; P<0.001), and higher hospital charges ($34 477 versus $14 921; P<0.001). There was 1 major adverse event in the CMR group (P=1.0). The operative course and frequency of postoperative complications were similar between the 2 groups. The proportion of patients who had a successful bidirectional Glenn operation was similar (71% versus 83%; P=0.3). At the 3-month follow-up, there were no differences in clinical status, oxygen saturation, or frequency of reinterventions. CMR is a safe, effective, and less costly alternative to routine catheterization in the evaluation of selected patients before bidirectional Glenn operation. Further studies are necessary to determine whether there are long-term benefits from transcatheter interventions in these patients.

Hybrid Approach Facilitates Use of a Minimized CPB Circuit and Transfusion Free Surgery in an Extended Norwood Stage II Procedure

Intraoperative stent implantation into a stenotic left pulmonary artery branch and surgical creation of a bidirectional Glenn anastomosis resulted in avoidance of aortic cross-clamping and transection of the aorta for surgical patching of the pulmonary artery. The hybrid approach thereby reduced the complexity of the surgical procedure, facilitated the use of a minimized cardiopulmonary bypass circuit, reduced the degree of hemodilution and blood trauma and resulted in transfusion-free surgery and excellent clinical outcome in an 11 kg child.

Experience With Bovine Pericardium for the Reconstruction of the Aortic Arch in Patients Undergoing a Norwood Procedure

The incidence of recurrent aortic arch obstruction after the Norwood procedure is between 0% and 36%. Allograft material is frequently used to enlarge the aorta; its use has been associated with the development of significant allosensitization. We report our experience using bovine pericardium for the reconstruction of the aortic arch in patients undergoing a Norwood procedure. A retrospective analysis of 33 consecutive patients evaluated for a second-stage procedure after an initial Norwood repair was performed. All patients underwent a cardiac catheterization. The presence of recurrent arch obstruction (gradient > 10 mm Hg) and its management were noted. Three consecutive patients were tested for anti-HLA antibodies at the time of their Fontan procedure. The mean age at the time of the cardiac catheterization was 4.12 months (range, 2 to 7 months). The incidence of recurrent arch obstruction was 18.2% (6 patients). Four patients (12.1%) had distal obstruction, 1 patient (3%) had proximal obstruction, and 1 patient (3%) had mid-transverse arch obstruction. Five of the 6 patients underwent aortic arch reintervention consisting of four balloon dilatations and two surgical patch aortoplasties. Thirty-one patients advanced to a second-stage procedure, including 30 bidirectional Glenn anastomoses, and 1 Rastelli repair. No significant allosensitization was present in the patients tested. The use of bovine pericardium in the Norwood procedure is associated with an acceptable incidence of recurrent arch obstruction. Its availability, lower cost, and possible immunologic advantages make it an attractive alternative to allograft material.

Surgical repair of coronary sinus orifice atresia with persistent left superior vena cava in heterotaxia

A 6-month-old boy was diagnosed with coronary sinus orifice atresia, double-outlet right ventricle, complete atrioventricular septal defect, pulmonary stenosis, and moderate common atrioventricular valve regurgitation associated with heterotaxy syndrome. Cardiac venous flow drained through a persistent left superior vena cava. We decided to perform coronary sinus orifice unroofing through the right atrium under a guide using a bougie. The persistent left superior vena cava was divided. Bidirectional Glenn anastomosis and edge-to-edge common atrioventricular valve repair were concomitantly performed. After a 1-year follow-up period, the patient is alive and well without any ischemic event.

Inhaled Nitric Oxide Use in Bidirectional Glenn Anastomosis for Elevated Glenn Pressures

Inhaled Nitric Oxide Use in Bidirectional Glenn Anastomosis for Elevated Glenn Pressures

Effect of patent ductus arteriosus stenting on subsequent bidirectional Glenn anastomosis: A word of caution

Effect of patent ductus arteriosus stenting on subsequent bidirectional Glenn anastomosis: A word of caution

Inhaled Nitric Oxide Use in Bidirectional Glenn Anastomosis for Elevated Glenn Pressures

Children frequently undergo bidirectional Glenn anastomosis in the staged surgical management of single ventricle physiology. The purpose of our study was to investigate the role of inhaled nitric oxide therapy in children with marked elevations in Glenn pressures after this surgery. A retrospective study over a 30-month period was performed. The effect of inhaled nitric oxide therapy was analyzed in children with marked elevations of Glenn pressures resulting in decreased systemic perfusion. Effects on Glenn pressures, respiratory indices, and systemic perfusion were evaluated after initiation of nitric oxide therapy and compared with baseline parameters. Sixteen patients were placed on nitric oxide therapy for marked elevations of Glenn pressures (22.4 +/- 3.9 mm Hg). In the 11 responsive patients, there were significant reductions in Glenn pressures (from 22.4 mm Hg to 17.1 mm Hg, p < 0.001) and significant improvement in partial pressure of oxygen to fraction of inspired oxygen ratio (from 49 to 74.3, p = 0.001) and oxygenation index (from 17 to 12, p = 0.005). There was simultaneous significant reduction in inotrope score (from 14.9 to 11.4, p < 0.001) and fluid volume support (from 11.4 mL/kg to 2.3 mL/kg, p < 0.001) in the responsive patients. Five patients that failed to show any response were found, subsequently, to have an anatomic lesion. Inhaled nitric oxide produces significant reduction in Glenn pressures and improvement in systemic perfusion and pulmonary gas exchange in patients with marked elevations of Glenn pressures after bidirectional Glenn anastomosis. Patients who fail to respond should be investigated for an anatomic lesion.

Invited commentary

In this retrospective review, Agarwal and colleagues [1Agarwal H.S. Churchwell K.B. Doyle T.P. et al.Inhaled nitric oxide use in bidirectional Glenn anastomosis for elevated Glenn pressures.Ann Thorac Surg. 2006; 81: 1429-1435Abstract Full Text Full Text PDF PubMed Scopus (24) Google Scholar] evaluated the effects of inhaled nitric oxide (iNO) in bidirectional Glenn patients who had elevated Glenn pressures immediately postoperatively. The effects of iNO on Glenn pressures, systemic perfusion, and respiratory indices were assessed. The study demonstrated that in a majority of these patients iNO lowered superior vena cava pressures and improved systemic perfusion and gas exchange. In the subset of patients who did not benefit from iNO, anatomic obstruction or ventricular dysfunction was subsequently noted, and those patients underwent further operative interventions. This study provides a basis for stepwise evaluation of postoperative Glenn patients with significantly elevated Glenn pressures and diminished clinical cardiac output. An early trial of iNO is warranted to determine whether hemodynamics are compromised due to elevated pulmonary vascular resistance (PVR). If the Glenn pressure does not fall to at least 17 mm Hg, then anatomic obstruction or ventricular dysfunction is likely, and an echocardiogram followed by cardiac catheterization is indicated. This series also suggests that there is a role for iNO in successfully getting patients with borderline preoperative pulmonary artery pressure and PVR through the immediate postoperative period after a Glenn procedure. Use of iNO empirically to come off cardiopulmonary bypass and in the early postoperative period may eliminate a detrimental period of low cardiac output for such patients, particularly for those who have long bypass times. Although not examined in this study, patients with elevated PVR preoperatively may benefit most by the complete avoidance of cardiopulmonary bypass during the Glenn procedure when possible. These results are thought provoking, because prior similar work looking at iNO in postoperative Glenn patients has yielded equivocal findings. Notably in this study, all of the patients who had elevated Glenn pressures postoperatively had significantly higher pulmonary artery pressures and pulmonary vascular resistance at preoperative catheterization. The postoperative Glenn pressures in these patients were more elevated than those of the patients in prior study populations. There may be a subset of single ventricle patients with altered endogenous nitric oxide synthesis or metabolism. In such patients with longstanding elevations in PVR, with additional endothelial dysfunction secondary to cardiopulmonary bypass, pulmonary blood flow may be limited postoperatively by pulmonary vasoconstriction. In those cases, as in this study, iNO may improve cardiac output and oxygenation through direct pulmonary vasodilation. On the other hand, exogenous nitric oxide may not provide much benefit in patients who do not have long-term alterations in pulmonary vascular tone. In those cases, iNO may have salutary effects on oxygenation only when there is intrapulmonary shunting. This study helps to identify a subgroup of patients who benefit from iNO in the early postoperative period. Similar work is needed to identify which single ventricle patients with elevated PVR would respond to chronic therapies. Inhaled Nitric Oxide Use in Bidirectional Glenn Anastomosis for Elevated Glenn PressuresThe Annals of Thoracic SurgeryVol. 81Issue 4PreviewChildren frequently undergo bidirectional Glenn anastomosis in the staged surgical management of single ventricle physiology. The purpose of our study was to investigate the role of inhaled nitric oxide therapy in children with marked elevations in Glenn pressures after this surgery. Full-Text PDF

Stroke following Glenn anastomosis in a child with inherited thrombophilia

The optimal anticoagulation following Fontan operation and its modifications remain controversial and it is even less well defined as regards patients with inherited thrombophilia. We present a case of a child with bidirectional Glenn anastomosis for double inlet left ventricle that suffered a stroke despite aspirin prophylaxis; the patient was combined homozygous for prothrombin G20210A mutation and for methylenetetrahydrofolate reductase C677T mutation as well. The family history was positive for fetal loss and premature cardiovascular disease. Large-scale studies are needed to evaluate whether carriers of thrombophilia mutations need more intense thromboprophylaxis.

Simultaneous Second-Stage Norwood Operation and Tracheoplasty

Tracheal stenosis is a rare complication that follows operations for congenital heart disease in the newborn period. We report the case of an infant with hypoplastic left heart syndrome who developed symptomatic tracheal stenosis 5 months after a first-stage Norwood operation. The combined surgical procedure of a bidirectional Glenn anastomosis and a tracheoplasty under cardiopulmonary bypass was undertaken.

Surgical management of unbalanced atrioventricular canal defect

Approximately 10% of endocardial cushion defects exhibit unbalance at the atrioventricular inlet. When the atrioventricular valve sits more over one ventricle than the other, the contralateral ventricle is typically hypoplastic. Surgical intervention for unbalanced atrioventricular canal has a much higher morbidity and mortality than for the balanced form of the defect. With unbalanced atrioventricular canal to the right, no universal criteria are in place to choose single versus biventricular repair. In many cases, risk factors have been extrapolated from other lesions with left ventricular hypoplasia. Even if biventricular repair is successful, the reoperation rate is high for this lesion. Little data exist in the literature regarding left unbalanced atrioventricular canal. In general, right ventricular hypoplasia is better tolerated than left ventricular hypoplasia, and biventricular repair is usually possible. If cyanosis or high systemic venous pressure results, the one and one half ventricle repair (biventricular repair with bidirectional Glenn anastomosis) is an option. This article reviews the present understanding of unbalanced atrioventricular canal and discusses diagnostic and surgical strategies for this complex lesion.

Right Ventricle-Pulmonary Artery Shunt in First-Stage Palliation of Hypoplastic Left Heart Syndrome

This article reviews our experience using a prosthetic conduit between the right ventricle (RV) and the pulmonary artery (PA), in lieu of the more traditional aortopulmonary shunt, for infants undergoing surgical palliation of hypoplastic left heart syndrome. Thirty-three consecutive infants underwent Norwood procedure between February 1998 and November 2003, using an RV-PA conduit. There were 31 hospital survivors (94%) and 25 patients have undergone a stage II bidirectional Glenn anastomosis with an additional two deaths. Nine patients have undergone completion Fontan. This technique provides reproducible results, simplifies postoperative management, and improves outcome, especially for low volume programs.

Experience over five years using a shunt placed between the right ventricle and the pulmonary arteries during initial reconstruction of hypoplasia of the left heart

the hypoplastic left heart syndrome includes a spectrum of underdevelopment of the left-sided cardiac structures, characterized by aortic valvar atresia or severe stenosis with a small ascending aorta and hypoplasia of the left ventricle. without surgical treatment, practically all infants with this complex cardiac anomaly die within the first month of life. since norwood et al. reported successful surgical palliation in 1981, multi-staged reconstructive surgery, involving the norwood procedure as the first stage, followed by a bi-directional glenn anastomosis and subsequent completion of the fontan circulation, has become the established surgical treatment.

The patterns of flow in the total extracardiac cavopulmonary connection

more than 30 years ago, fontan and baudet proposed bypass of a dysfunctional right ventricle by connecting the pulmonary arteries directly to the right atrium, the so-called atriopulmonary anastomosis. since then, much experience has been accrued in the field of the functionally univentricular circulation. the proposed connections have been subjected to several modifications, aiming towards minimizing the losses of energy in the cavopulmonary system, and thereby improving the clinical outcomes. a remarkable improvement was achieved with the introduction of the concept of the total cavopulmonary connection, specifically the combination of a bi-directional glenn anastomosis with a tubular intracardiac extension from the inferior caval venous to the pulmonary arteries. this design was shown to avoid the dissipation of energy associated with the swirling patterns seen in the traditional atrio-pulmonary anastomosis.

Functional acquired pulmonary atresia secondary to subpulmonary aneurysmal tissue: a rare form of pulmonary outflow tract obstruction

artery (PA) arising from rudimentary pouch (*). Fetal echocardiography was performed at 19 and 29 weeks gestation after an abnormal screening ultrasound suggested left heart hypoplasia. The echocardiogram revealed left-sided hypoplasia with d-transposition of the great arteries and a small, posteriorly positioned pulmonary artery (PA) with both prograde and retrograde flow demonstrated. There appeared to be a moderate ventricular septal defect and, of note, there was unusual aneurysmal tissue of indeterminate origin below the pulmonary annulus. Postnatal echocardiography confirmed d-transposition of the great arteries with the aorta anterior and rightward of the smaller PA. The PA arose directly from a rudimentary, aneurysmal blind pouch (Figure 1) with bidirectional flow between the blind pouch and the main PA (Figure 2). However, no communication between the pouch and the remainder of the heart could be demonstrated by Doppler interrogation. The aneurysmal pouch was centrally located in the heart and appeared to possibly consist of redundant atrioventricular (AV) valve tissue contiguous with a leaflet of the left-sided AV valve. The PA was supplied by a large, tortuous patent ductus arteriosus typical for pulmonary atresia. There were 2 distinct AV valves entering a common single ventricle, with hypoplasia of the left-sided AV valve noted. The patient was initially treated with prostaglandin infusion to maintain ductal patency, followed by placement of a right-sided Blalock-Taussig shunt in the neonatal period. She subsequently underwent successful bidirectional Glenn anastomosis and left pulmonary arterioplasty at 7 months of age. This case represents an extremely unusual form of functional pulmonary atresia in which abnormal intracardiac aneurysmal tissue of indeterminate ori-