Hybrid Palliation for Interrupted Aortic Arch With Small Aortic Valve.

OBJECTIVES: Open heart surgery for interrupted aortic arch in the neonatal period is still a high-risk procedure related in part to patient factors such as low birth weight, other morphologic anomalies, and, especially, small aortic valve size. Recently, we performed hybrid palliation with bilateral pulmonary artery banding and ductal stenting as the first-stage palliation for such cases. In this study, the outcomes of this procedure were examined. METHODS: Six cases of interrupted aortic arch with a small aortic valve underwent the hybrid procedure in the neonatal period in our institute from 2010 to 2015 (mean age: 6.8 days, mean body weight: 3.2 kg, mean z score of the aortic valve annulus: -8.3). Their postoperative clinical courses and results of the second-stage surgery were evaluated. RESULTS: No mortality or severe morbidity was seen in association with initial hybrid palliation. Five of six patients were discharged from the hospital; the one exception had a significant urinary tract anomaly. None needed an additional catheter intervention or surgical procedure postoperatively. All surviving patients underwent second-stage surgery; three had biventricular repair by the conventional method or Damus-Kaye-Stansel anastomosis with the Rastelli procedure and the other three proceeded toward staged Fontan reconstruction. Growth of the aortic valve was seen in four patients, and increased indexed left ventricle volume was recognized in one after the palliation. CONCLUSION: Hybrid palliation could be useful not only to avoid high-risk neonatal surgery but also to allow for eventual selection of the second-stage surgery based on the observations of potential interval development of left ventricular structures.

Evaluation of 60 cases of systemic-pulmonary shunt with cardiopulmonary bypass.

OBJECTIVE: In recent years, the median sternotomy approach with cardiopulmonary bypass has been increasingly chosen when systemic-pulmonary shunt surgery is performed as initial palliation for congenital heart diseases with decreased pulmonary blood flow to secure a stable surgical field and to maintain a stable circulation and oxygen supply. Since 2007, this strategy has been applied in our institute. This time, we examine the advantage and disadvantage of this procedure by evaluating the intraoperative and postoperative courses. METHODS: The study investigated 60 cases that underwent systemic-pulmonary shunt surgery under cardiopulmonary bypass at our facility after August 2007. Original diagnosis, age and body weight at surgery, shunt procedure, concomitant procedure, and surgical times were evaluated. The postoperative course of each case and the results of subsequent surgeries were also examined. RESULTS: No death or severe complication occurred during surgery or in the perioperative period. The age at surgery was 4 days-12 years (median 5.1 months), and the body weight was 2.3-28.1 (median 4.7) kg. Surgical procedures were as follows: right modified Blalock-Taussig shunt (mBTS): 35, left mBTS: 11, and central shunt: 14. In addition, the following simultaneous surgeries were conducted: pulmonary artery plasty: 11, unifocalization: 5, main pulmonary artery ligation: 2, interatrial communication enlargement: 4, and total anomalous pulmonary venous drainage repair: 2. CONCLUSION: The outcomes at our facility have validated the safety of systemic-pulmonary shunt surgeries under cardiopulmonary bypass, and even the disadvantages of concern were believed to be within acceptable limits. Further innovation and examination are important in pursuit of even less invasive surgeries.

Giant epicardial cyst presenting as acute cardiac tamponade in a 2-year-old boy.

Cystic structures within the pericardial cavity are rare. They are divided into epicardial and pericardial variants. Pericardial and epicardial cysts rarely cause symptoms. This report describes a case of epicardial cyst with acute cardiac tamponade in a 2-year-old boy with no previous cardiac history who was transferred to our hospital because of hemodynamic instability. Emergency drainage of the pericardial effusion and complete excision of the cyst were performed through a median full sternotomy.

Influence of bidirectional cavopulmonary anastomosis and concomitant valve repair on atrioventricular valve annulus and function.

BACKGROUND: The relationship between atrioventricular valve regurgitation (AVVR) and valve annulus after bidirectional cavopulmonary anastomosis (BCPA) and adequate indications for valve repair are unclear. METHODS: We evaluated the size of the valve annulus and the grade of AVVR before and immediately after BCPA, and at the most recent follow-up before the Fontan operation in 37 patients with a functional single ventricle. RESULTS: Nine patients underwent concomitant valve surgery. The mean z value of the valve annulus was significantly lower postoperatively than preoperatively in the 28 patients who were not treated by valve surgery (0.45 vs 1.51, p=0.01). However, mean regurgitation scores did not significantly change after BCPA (1.60 vs 1.78, p=0.08). The most recent assessment showed that the mean z value increased compared with that immediately after BCPA (1.36 vs 0.45, p=0.005). This increase was significant in the patients with moderate regurgitation. The mean z value of the valve annulus of the patients treated by concomitant valvuloplasty was significantly lower postoperatively than preoperatively (-0.25 vs 3.9, p=0.0001) and remained low at the latest evaluation. Mean regurgitation scores also significantly decreased after BCPA (2.25 vs 3.37, p=0.007). CONCLUSIONS: Unloading the systemic ventricle by BCPA leads to a decrease in the relative size of the atrioventricular valve. However, this decrease does not improve the degree of AVVR in the absence of concomitant valve repair. Concomitant valve repair is justified in patients with moderate or worse AVVR and an abnormal valve structure.

A case of ventricular septal defect and mitral insufficiency after blunt trauma.

Few reports have described traumatic heart injury in children. We describe a case of acute mitral regurgitation associated with papillary muscle rupture, traumatic ventricular septal defect, and impending left ventricular free wall rupture due to blunt trauma in a 2-year-old girl. The papillary muscle was sutured to the left ventricular free wall. The septal defect and surrounding ruptured muscle were covered with a pericardial patch, and a Hemashield patch was used to close the ventriculotomy. A residual defect caused by dehiscence of the pericardial patch necessitated reoperation 10 months later. The patient is currently being observed on an outpatient basis.

Cardiopulmonary bypass through a left thoracotomy using venous drainage from the innominate vein in congenital heart surgery.

Cardiopulmonary bypass (CPB) through a left lateral thoracotomy is a useful approach for some congenital heart procedures, although vascular access for the arterial and venous cannulation can be challenging in the selective patients. Six patients underwent successful extracorporeal circulation through a left lateral thoracotomy using the innominate vein for venous drainage. No operative deaths or major complications occurred. Venous drainage solely from the innominate vein was adequate to establish partial bypass without the need for pericardiotomy. Total bypass was established with combined venous drainage from the innominate vein and the main pulmonary artery. Exposure of the systemic atrioventricular valve was excellent through a left thoracotomy. Venous drainage from the innominate vein without using atrial drainage can safely be used for extracorporeal circulation through a left lateral thoracotomy without compromising the procedure and it is a useful approach to congenital heart surgery in selected patients.

Extracardiac conduit Fontan procedure versus intra-atrial lateral tunnel Fontan procedure.

The Fontan procedure has provided excellent surgical palliation for patients with various types of univentricular hearts, and it has evolved over time. Among many modifications, the lateral tunnel Fontan connection (LTF) and the extracardiac Fontan connection (ECF) are currently the most popular techniques for completing the total cavopulmonary connection. The advantages and disadvantages of both techniques are reviewed here. The advantages of the ECF includes adaptability to all types of univentricular hearts, ease of construction without aortic cross clamping and fewer atrial suture lines. The advantages of the LTF include the ability to complete Fontan circulation in young, very small patients with potential for growth. This review also compares post-operative arrhythmias and fluid dynamics associated with both techniques.

Unilateral pulmonary artery banding to promote contralateral pulmonary artery growth.

A full-term baby with double-outlet right ventricle and total anomalous pulmonary venous connection (TAPVC) complicated with left main pulmonary artery (PA) stenosis, presented with heart failure caused by increased pulmonary blood flow. Based on significant discrepancies in size and development between the left and right PAs, we performed right PA banding concomitant with TAPVC repair to promote left PA growth and restrict overall PA flow. PA-graphy performed 3 months after surgery showed marked increase in the left PA size with appropriately low pressure, which enabled us to successfully complete Glenn anastomosis. Under appropriate patient selection, unilateral PA banding for patients with unbalanced peripheral PA size could serve as an effective and less invasive strategy to simultaneously promote PA growth and control PA flow.

Modified versus conventional ultrafiltration in pediatric cardiac surgery: a meta-analysis of randomized controlled trials comparing clinical outcome parameters.

OBJECTIVE: Although previous studies have demonstrated that modified ultrafiltration improves laboratory parameters in pediatric cardiac surgery, the clinical outcome data have been inconsistent. We performed a meta-analysis of randomized controlled trials comparing modified versus conventional ultrafiltration. METHODS: We conducted a comprehensive search of the literature to identify clinical trials that met our inclusion criteria. To be included, studies had to be prospective randomized trials that compared modified ultrafiltration and conventional ultrafiltration in pediatric cardiac surgery using cardiopulmonary bypass. We focused on the following outcome variables: hematocrit and mean arterial blood pressure after cardiopulmonary bypass, amount of chest tube drainage after surgery, time to extubation, and length of stay in the intensive care unit. The random effects model was used to determine the pooled effect estimates. The estimators of treatment effects were expressed as the weighted mean difference with 95% confidence intervals. The heterogeneity of collected data was also evaluated. RESULTS: We screened 54 studies, 8 of which satisfied our inclusion criteria. Combined analysis revealed that modified ultrafiltration resulted in significantly higher postbypass hematocrit and higher mean arterial blood pressure. Benefits in postoperative blood loss, ventilator time, and intensive care unit stay were not apparent. There was significant heterogeneity among the studies surveyed. CONCLUSIONS: The advantage of modified ultrafiltration over conventional ultrafiltration consists of significant improvement of clinical conditions in the immediate postbypass period. The postoperative outcome parameters were not significantly influenced. We should also take into account possible clinical or methodologic variations in the currently available ultrafiltration studies.

Coronary re-implantation after completion of neo-aortic reconstruction in arterial switch operation: accurate intraoperative assessment for the optimal re-implantation site.

The arterial switch operation (ASO) has evolved into the treatment of the choice for most forms of transposition of the great arteries (TGA). Despite advancement in the technical aspects of the procedure, certain anatomical variations of the coronary arteries are still considered as surgical risks. We have recently employed a novel technique for coronary artery reconstruction in ASO to achieve further improvement of coronary transfer in cases with complex coronary anatomy. The technical key of the procedure is that reconstruction of the coronary arteries is preceded by neo-aortic anastomosis. After neo-aortic reconstruction is accomplished, the neo-aorta is temporarily distended with removal of the cross-clamp. The distended neo-aorta informs us its postsurgical geometry, which facilitates accurate assessment for the optimal site of coronary button transfer. The technique was feasible in 13 of 15 children who were consecutively treated by our group between 2003 a nd 2008. All patients recovered uneventfully and no coronary perfusion issue has occurred during the follow-up period. However, the complex anatomy of the coronary arteries in two children was not amenable to this technique. One with double loops (1RL; 2Cx) accompanied by side-by-side relationship of the great arteries underwent the open trapdoor technique, while the other with intramural coronary artery underwent the Imai method, that is one of procedure in which the coronary arteries are left in situ. The coronary re-implantation after neo-aortic reconstruction is promising to minimize postsurgical coronary ischemia and suitable for most ASO cases. However, various modifications of coronary transfer are required in a few variations of the coronary anatomy and we have to pursue further technical refinement of coronary artery transfer in ASO.

Ventricular-vascular stiffening in patients with repaired coarctation of aorta: integrated pathophysiology of hypertension.

BACKGROUND: Despite successful repair, patients with coarctation of the aorta (COA) often show persistent hypertension at rest and/or during exercise. Previous studies indicated that the hypertension is mainly due to abnormalities in the arterial bed and its regulatory systems. We hypothesized that ventricular systolic stiffness also contributes to the hypertensive state in these patients in addition to increased vascular stiffness. METHODS AND RESULTS: The study involved 43 patients with successfully repaired COA and 45 age-matched control subjects. Ventricular systolic stiffness (end systolic elastance) and arterial stiffness (effective arterial elastance) were measured invasively by ventricular pressure-area relationship during varying preload before and after beta-adrenergic stimulation. The mean systolic blood pressure was significantly higher with concomitant increases in both end systolic elastance and effective arterial elastance in patients with COA compared with control subjects (113.2+/-16.8 versus 91.0+/-9.1 mm Hg, 44.5+/-17.0 versus 19.2+/-6.7 mm Hg/mL/m(2), and 27.8+/-11.4 versus 20.2+/-4.8 mm Hg/mL/m(2), respectively; P<0.01 for each). End systolic elastance and effective arterial elastance of patients with COA showed exaggerated responses to beta-adrenergic stimulation, further amplifying blood pressure elevation. Quantification analyses assuming that ventricular systolic stiffness of patients with COA is equal to that of the control revealed that ventricular systolic stiffness accounts for approximately 50% to 70% of the elevated blood pressure in patients with COA. Furthermore, combined ventricular-arterial stiffening amplified systolic pressure sensitivity to increased preload during abdominal compression and limited stroke volume gain/relaxation improvement induced by beta-adrenergic stimulation. CONCLUSIONS: Increased ventricular systolic stiffness, coupled with increased arterial stiffness, plays important roles in hypertension in patients with repaired COA. Thus, ventricular systolic stiffness is a potentially suitable target for reduction of blood pressure and improvement of prognosis of patients with COA.

Sedation of hypercyanotic spells in a neonate with tetralogy of Fallot using dexmedetomidine.

OBJECTIVE: Sedation is an important step in the management of patients with hypercyanotic spells associated with tetralogy of Fallot (TOF) to ameliorate and prevent recurrence of cyanosis. This case report illustrates the effectiveness of dexmedetomidine-induced sedation in the management of hypercyanotic spells in a neonate with TOF. DESCRIPTION: An 8-day-old term newborn patient with TOF showed hypercyanotic spells, as indicated by an abrupt decrease in arterial saturation (SpO2) level measured by a pulse oximeter from 80% to as low as 50%, when the patient became irritable and agitated. We started continuous infusion of dexmedetomidine at a dose of 0.2 microg/kg/min without a loading bolus injection. About half an hour after commencement of dexmedetomidine infusion, the patient reached an acceptable level of sedation, together with a drop in heart rate by approximately 20 beats/min. There was no apparent respiratory depression or marked change in blood pressure. SpO2 was also stable during dexmedetomidine infusion. The patient underwent a successful Blalock-Taussig shunt operation on the next day of admission. COMMENTS: Dexmedetomidine may be useful for the management of hypercyanotic spells in pediatric patients with TOF.

O uso de dexmedetomidina na sedação de crises hipercianóticas em um recém-nascido com tetralogia de Fallot / Sedation of hypercyanotic spells in a neonate with tetralogy of Fallot using dexmedetomidine

OBJETIVO: A sedação é um passo importante para aliviar e prevenir a recorrência de cianose no manejo de pacientes com crises hipercianóticas associadas à tetralogia de Fallot (T4F). Este relato de caso ilustra a eficácia da sedação induzida por dexmedetomidina no manejo de crises hipercianóticas em um recém-nascido com T4F. DESCRIÇÃO: Um paciente recém-nascido a termo de 8 dias de idade com T4F apresentava crises hipercianóticas, indicadas por quedas abruptas no nível de saturação arterial (SpO2), medido por um oxímetro de pulso, de 80 por cento até 50 por cento, quando o paciente ficava agitado ou irritável. Nós começamos a infusão contínua de dexmedetomidina em uma dosagem de 0,2 µg/kg/min sem injeção de ataque em bolus. Cerca de meia hora depois do início da infusão de dexmedetomidina, o paciente atingiu um nível aceitável de sedação, e sua freqüência cardíaca diminuiu aproximadamente 20 batidas por minuto. Não houve nenhuma depressão respiratória aparente ou mudança acentuada em sua pressão arterial. A SpO2 também continuou estável durante a infusão de dexmedetomidina. No dia seguinte à sua hospitalização, o paciente passou com sucesso por uma operação de anastomose de Blalock-Taussig. COMENTÁRIOS: A dexmedetomidina pode ser útil no manejo de crises hipercianóticas em pacientes pediátricos com T4F.

OBJECTIVE:Sedation is an important step in the management of patients with hypercyanotic spells associated with tetralogy of Fallot (TOF) to ameliorate and prevent recurrence of cyanosis. This case report illustrates the effectiveness of dexmedetomidine-induced sedation in the management of hypercyanotic spells in a neonate with TOF. DESCRIPTION: An 8-day-old term newborn patient with TOF showed hypercyanotic spells, as indicated by an abrupt decrease in arterial saturation (SpO2) level measured by a pulse oximeter from 80 percent to as low as 50 percent, when the patient became irritable and agitated. We started continuous infusion of dexmedetomidine at a dose of 0.2 µg/kg/min without a loading bolus injection. About half an hour after commencement of dexmedetomidine infusion, the patient reached an acceptable level of sedation, together with a drop in heart rate by approximately 20 beats/min. There was no apparent respiratory depression or marked change in blood pressure. SpO2 was also stable during dexmedetomidine infusion. The patient underwent a successful Blalock-Taussig shunt operation on the next day of admission. COMMENTS: Dexmedetomidine may be useful for the management of hypercyanotic spells in pediatric patients with TOF.

Bridge to transplantation with a Toyobo-NCVC left ventricular assist device in a 3-year-old girl.

In Japan, no pulsatile ventricular assist devices are available specifically for use in children. Pumps designed for adults are thus often used in children. We report herein a case of end-stage heart failure in a 3-year old girl (height 100.4 cm; body weight 16.2 kg; body surface area 0.66 m2) who underwent implantation with an adult-sized Toyobo-NCVC left ventricular assist device (Toyobo-National Cardiovascular Center, Osaka, Japan) in our unit. We started with the driving mode to "full-fill, full-empty" mode. The problem was difficult-to-treat hypertension due to excessive stroke volume induced by the left ventricular assist device. Aggressive administration of antihypertensive therapy was needed. Successful heart transplantation was performed in Germany 5 months after beginning support with the Toyobo-NCVC left ventricular assist device.

Successful use of the Toyobo left ventricular assist device in a 16-kg girl awaiting cardiac transplantation.

In Japan, no mechanical circulatory support is available for children. We report a case of terminal stage cardiac failure in a 16-kg girl who was implanted with an adult-sized Toyobo-NCVC left ventricular assist device (Toyobo-National Cardiovascular Center, Osaka, Japan) in our unit. She successfully underwent heart transplantation in the United States 5 months later.

Recurrent discrete subaortic stenosis and small aortic annulus successfully repaired by the Konno procedure in a young woman.

A 24-year-old woman who had undergone excision of the membrane for discrete subaortic stenosis when 6 years old displayed recurrent subaortic stenosis and had a small aortic annulus, with a peak pressure gradient of 60mmHg. We chose to perform the Konno operation with a mechanical valve. This released the left ventricular outflow tract obstruction adequately, and she recovered uneventfully with New York Heart Association functional class I. In our experience, an aggressive strategy such as myectomy is an appropriate initial procedure for preventing recurrence when the geometry of the problem may lead to recurrence in the left ventricular outflow tract. The Konno operation is a good option for recurrent subaortic stenosis with small aortic annulus.