Bloodless Repair of Aortic Arch with Dual Aortic Cannulation in a Jehovah's Witness Patient.

Various methods for surgical repair of the aortic arch are described throughout the literature with many focused on cannulation techniques and degree of systemic cooling in an effort to reduce postoperative morbidities. Despite advancements in techniques, this surgery is still often associated with higher levels of blood loss and subsequent allogenic blood transfusions. Although blood products can be safely transfused to the majority of patients undergoing repair of the aortic arch, the complexity and risk is further multiplied when the patient is of Jehovah's Witness faith and refuses blood transfusions. This paper will detail our technique of surgical repair of the aortic arch in a Jehovah's Witness patient with dual aortic cannulation and our multidisciplinary approach to avoiding blood products.

Increased hepatic stiffness as consequence of high hepatic afterload in the Fontan circulation: a vascular Doppler and elastography study.

UNLABELLED: Hepatic dysfunction is a recognized complication after Fontan palliation of congenital heart disease. We sought to quantitatively measure hepatic stiffness and vascular Doppler indices using ultrasound (US) and shear wave elastography (SWE) in a Fontan cohort. Subjects were prospectively recruited for echocardiography and real-time hepatic duplex US with SWE for hepatic stiffness (kPa). Doppler peak velocities, velocity time integral, resistive, pulsatility, acceleration indices (RI, PI, AI), and flow volume were measured in celiac artery, superior mesenteric artery, and main portal vein (MPV). A subset underwent cardiac catheterizations with liver biopsy. Correlations were explored between SWE, duplex, hemodynamic, and histopathologic data. In all, 106 subjects were studied including 41 patients with Fontan physiology (age 13.8 ± 6 years, weight 45.4 ± 23 kg) and 65 controls (age 15.0 ± 8.4 years, weight 47.9 ± 22 kg). Patients with Fontan physiology had significantly higher hepatic stiffness (15.6 versus 5.5 kPa, P < 0.0001), higher celiac RI (0.78 versus 0.73, P = 0.04) superior mesenteric artery RI (0.89 versus 0.84, P = 0.005), and celiac PI (1.87 versus 1.6, P = 0.034); while MPV flow volume (287 versus 420 mL/min in controls, P = 0.007) and SMA AI (829 versus 1100, P = 0.002) were lower. Significant correlation was seen for stiffness with ventricular end-diastolic pressure (P = 0.001) and pulmonary artery wedge pressure (P = 0.009). Greater stiffness correlated with greater degrees of histopathologic fibrosis. No significant change was seen in stiffness or other duplex indices with age, gender, time since Fontan, or ventricular morphology. CONCLUSION: Elevated hepatic afterload in Fontan, manifested by high ventricular end-diastolic pressures and pulmonary arterial wedge pressures, is associated with remarkably increased hepatic stiffness, abnormal vascular flow patterns, and fibrotic histologic changes. The MPV is dilated and carries decreased flow volume, while the celiac and superior mesenteric arterial RI is increased. SWE is feasible in this population and shows promise as a means for predicting disease severity on liver biopsy.

Considerations for the use of porcine organ donation models in preclinical organ donor intervention research.

Use of animal models in preclinical transplant research is essential to the optimization of human allografts for clinical transplantation. Animal models of organ donation and preservation help to advance and improve technical elements of solid organ recovery and facilitate research of ischemia-reperfusion injury, organ preservation strategies, and future donor-based interventions. Important considerations include cost, public opinion regarding the conduct of animal research, translational value, and relevance of the animal model for clinical practice. We present an overview of two porcine models of organ donation: donation following brain death (DBD) and donation following circulatory death (DCD). The cardiovascular anatomy and physiology of pigs closely resembles those of humans, making this species the most appropriate for pre-clinical research. Pigs are also considered a potential source of organs for human heart and kidney xenotransplantation. It is imperative to minimize animal loss during procedures that are surgically complex. We present our experience with these models and describe in detail the use cases, procedural approach, challenges, alternatives, and limitations of each model.

Safety of cardiac magnetic resonance and contrast angiography for neonates and small infants: a 10-year single-institution experience.

BACKGROUND: With increasing applications of cardiac magnetic resonance (CMR) and magnetic resonance angiography (MRA) for evaluation of congenital heart disease (CHD), safety of this technology in the very young is of particular interest. OBJECTIVE: We report our 10-year experience with CMR in neonates and small infants with particular focus on the safety profile and incidence of adverse events (AEs). MATERIALS AND METHODS: We reviewed clinical, anesthesia and nursing records of all children ≤120 days of age who underwent CMR. We recorded variables including cardiac diagnosis, study duration, anesthesia type and agents, prostaglandin E1 (PGE1) dependence and gadolinium (Gd) use. Serially recorded temperature, systemic saturation (SpO(2)) and cardiac rhythm were analyzed. Primary outcome measure was any AE during or <24 h after the procedure, including minor AEs such as hypothermia (axillary temperature ≤95 °F), desaturation (SpO(2) drop ≥10% below baseline) and bradycardia (heart rate ≤100 bpm). Secondary outcome measure was unplanned overnight hospitalization of outpatients. RESULTS: Children (n = 143; 74 boys, 69 girls) had a median age of 6 days (1-117), and 98 were ≤30 days at the time of CMR. The median weight was 3.4 kg (1.4-6 kg) and body surface area 0.22 m(2) (0.13-0.32 m(2)). There were 118 (83%) inpatients (108 receiving intensive care) and 25 (17%) outpatients. Indications for CMR were assessment of aortic arch (n = 57), complex CHD (n = 41), pulmonary veins (n = 15), vascular ring (n = 8), intracardiac mass (n = 8), pulmonary artery (n = 7), ventricular volume (n = 4), and systemic veins (n = 3). CMR was performed using a 1.5-T scanner and a commercially available coil. CMR utilized general anesthesia (GA) in 86 children, deep sedation (DS) in 50 and comforting methods in seven. MRA was performed in 136 children. Fifty-nine children were PGE1-dependent and 39 had single-ventricle circulation. Among children on PGE1, 43 (73%) had GA and 10 (17%) had DS. Twelve children (9%) had adverse events (AEs)-one major and 11 minor. Of those 12, nine children had GA (10%) and three had DS (6%). The single major AE was respiratory arrest after DS in a neonate (resuscitated without sequelae). Minor AEs included desaturations (n = 2), hypothermia (n = 5), bradycardia (n = 2), and bradycardia with hypoxemia (n = 2). Incidence of minor AEs was 9% for inpatients (vs. 4% for outpatients), and 8% for neonates (vs. 9% for age ≥30 days). Incidence of minor AEs was similar between PGE1-dependent infants and the non-PGE1 group. There were no adverse events related to MRA. Of 25 outpatients, 5 (20%) were admitted for overnight observation due to desaturations. CONCLUSION: CMR and MRA can be accomplished safely in neonates and infants ≤120 days old for a wide range of pre-surgical cardiac indications. Adverse events were unrelated to patient age, complexity of heart disease, type of anesthesia or PGE1 dependence.

Thoracoabdominal Normothermic Perfusion in Donation After Circulatory Death.

Donation after circulatory death is emerging as an alternative pathway to donation after brain death to expand the cardiac organ donor pool. We describe the surgical technique and circuit configuration for in-situ organ reperfusion with thoracoabdominal normothermic regional perfusion using portable venoarterial extracorporeal membrane oxygenation.

Self-reported functional health status following interrupted aortic arch repair: A Congenital Heart Surgeons' Society Study.

OBJECTIVES: Improved survival after congenital heart surgery has led to interest in functional health status. We sought to identify factors associated with self-reported functional health status in adolescents and young adults with repaired interrupted aortic arch. METHODS: Follow-up of survivors (aged 13-24 years) from a 1987 to 1997 inception cohort of neonates included completion of functional health status questionnaires (Child Health Questionnaire-CF87 [age <18 years, n = 51] or the Short Form [SF]-36 [age ≥18 years, n = 66]) and another about 22q11 deletion syndrome (22q11DS) features (n = 141). Factors associated with functional health status domains were determined using multivariable linear regression analysis. RESULTS: Domain scores of respondents were significantly greater than norms in 2 of 9 Child Health Questionnaire-CF87 and 4 of 10 SF-36 domains and only lower in the physical functioning domain of the SF-36. Factors most commonly associated with lower scores included those suggestive of 22q11DS (low calcium levels, recurrent childhood infections, genetic testing/diagnosis, abnormal facial features, hearing deficits), the presence of self-reported behavioral and mental health problems, and a greater number of procedures. Factors explained between 10% and 70% of domain score variability (R2 = 0.10-0.70, adj-R2 = 0.09-0.66). Of note, morphology and repair type had a minor contribution. CONCLUSIONS: Morbidities associated with 22q11DS, psychosocial issues, and recurrent medical issues affect functional health status more than initial morphology and repair in this population. Nonetheless, these patients largely perceive themselves as better than their peers. This demonstrates the chronic nature of interrupted aortic arch and suggests the need for strategies to decrease reinterventions and for evaluation of mental health and genetic issues to manage associated deteriorations.

Hepatic stiffness in the bidirectional cavopulmonary circulation: The Liver Adult-Pediatric-Congenital-Heart-Disease Dysfunction Study group.

OBJECTIVES: We hypothesized that hepatic injury in single-ventricle CHD has origins that predate the Fontan operation. We aimed to measure hepatic stiffness using ultrasound and shear wave elastography (SWE) in a bidirectional cavopulmonary connection (BCPC) cohort. METHODS: Subjects were prospectively recruited for real-time, hepatic, ultrasound-SWE for hepatic stiffness (kPa) and echocardiography. Doppler velocities, a velocity-time integral, flow volume, and resistive index, pulsatility index, and acceleration index were measured in celiac and superior mesenteric arteries, and in the main portal vein (MPV). Comparisons were made among subjects who had BCPC, subjects who were healthy, and a cohort of patients who had undergone the Fontan procedure. RESULTS: Forty subjects (20 patients who had BCPC; 20 age- and gender-matched control subjects) were studied. The hepatic stiffness in BCPC was elevated, compared with that in control subjects (7.2 vs 5.7 kPa; P = .039). Patients who had BCPC had significantly higher celiac artery resistive index (0.9 vs 0.8; P = .002); pulsatility index (2.2 vs 1.7; P = .002); and systolic-diastolic flow ratio (10.1 vs 5.9; P = .002), whereas the superior mesenteric artery acceleration index (796 vs 1419 mL/min in control subjects; P = .04) was lower. An elevated resistive index (0.42 vs 0.29; P = .002) and pulsatility index (0.55 vs 0.35; P = .001) were seen in MPV, whereas MPV flow was reduced (137.3 vs 215.7 mL/min in control subjects; P = .036). A significant correlation was found for hepatic stiffness with right atrial pressure obtained at catheterization (P = .002). Comparison with patients who underwent the Fontan procedure showed patients who had BCPC had lower hepatic stiffness (7.2 vs 15.6 kPa; P < .001). CONCLUSIONS: Hepatic stiffness is increased with BCPC physiology, and this finding raises concerns that hepatopathology in palliated, single-ventricle CHD is not exclusively attributable to Fontan physiology. Hepatic stiffness measurements using SWE are feasible in this young population, and the technique shows promise as a means for monitoring disease progression.

The significance of baseline cerebral oxygen saturation in children undergoing congenital heart surgery.

OBJECTIVES: Despite recent significant improvement in outcome, children undergoing surgery for correction of congenital heart defects have a persistent and troublesome mortality rate and incidence of neurologic complications. Recent data suggest that some congenital heart defects are associated with abnormal brain development and with low cerebral blood flow. We hypothesized that some children with congenital heart disease have an abnormally low baseline (preoperative) cerebral oxygen saturation (ScO2). METHODS: ScO2 was continuously recorded intraoperatively in 143 infants and children (age <18 years) undergoing repair of congenital heart defects on cardiopulmonary bypass. Baseline saturation was obtained prior to induction of anesthesia. Preoperative and postoperative saturations were correlated with the patient's physiology (cyanotic vs. acyanotic, presence of ventricular- or arterial-level left-to-right shunts) and outcome. RESULTS: Patient age ranged from 2 days to 17 years (median 8 months). Mean baseline ScO2 was 64%. Preoperative ScO2 was lower in infants with left to right shunt physiology (P < .01), but not in cyanotic infants without left-to-right shunts. Perioperative death was associated with baseline saturation less than 50%. CONCLUSIONS: Baseline ScO2 is lower in patients with left-to-right shunt physiology. Postoperative saturation is lower in patients with left-to-right shunt physiology and in cyanotic patients. Low baseline ScO2 predicts perioperative mortality in children with congenital heart disease. Measurement of ScO2 preoperatively will provide additional information for parent counseling, and preoperative optimization of ScO2 may improve outcome.

Intraoperative device closure of perimembranous ventricular septal defects without cardiopulmonary bypass: preliminary results with the perventricular technique.

OBJECTIVE: In infants undergoing closure of perimembranous ventricular septal defects, cardiopulmonary bypass remains one of the factors that prolongs hospital stay and morbidity. A new technique was used to close the defects under echocardiographic guidance without cardiopulmonary bypass to prevent the deleterious effects of bypass. METHODS: Recently, the Amplatzer membranous ventricular septal defect device (AGA Medical Corp, Golden Valley, Minn) was introduced. The device has a double-disc design with a short connecting waist. The left ventricular disc has an eccentric design to prevent encroachment on the aortic valve leaflets. Eight Yucatan miniature pigs with naturally occurring perimembranous ventricular septal defects underwent closure of the defect in the operating room by using the perventricular technique. After median sternotomy, a purse-string suture was placed on the free wall of the right ventricle. An angiocatheter was advanced in the right ventricle, and through the catheter, a wire was advanced from the right ventricle through the ventricular septal defect into the left ventricle. A delivery sheath and the dilator were advanced over the wire. The wire and catheter were removed, and an appropriately sized Amplatzer membranous device was advanced through the sheath. The device was deployed under echocardiographic guidance with the heart beating. RESULTS: The procedure was successful in all animals. There was no incidence of device embolization, heart block, or aortic insufficiency. Angiograms at 3 and 6 months revealed no residual defects and no aortic insufficiency. Pathologically, the devices were completely endothelialized when examined grossly. CONCLUSIONS: The perventricular technique appears to be excellent for closure of perimembranous ventricular septal defects in the operating room. The technique might be feasible in smaller babies, who are high-risk candidates for closure in the catheterization laboratory. Cardiopulmonary bypass and prolonged hospital stay are avoided.

Extended support with the Terumo Baby-RX oxygenator.

The Terumo Baby-RX, a new-generation low prime oxygenator, recently has entered the perfusion market in North America. This oxygenator is designed exclusively for neonates and infants and has the smallest priming volume of any clinically available oxygenator. The BABY-RX also is treated with X Coating, Terumo's biocompatible, hydrophilic polymer surface coating that reduces platelet adhesion and protein denaturation. The oxygenator has a blood flow range of 0.1 to 1500 mL/min and operates with a minimum reservoir volume of 15 mL. A 3.2-kg patient, status post-Stage 1 Norwood, Palliation was placed on cardiopulmonary support after thrombus formation within the modified Blalock-Taussig shunt during a general surgery procedure. The extended support circuit incorporated the Baby-RX oxygenator for 17.5 hours. The oxygenator performed well over this time period at flows of 600-800 mL/min, sweep rates of 100-300 mL/min, FiO2 of 30-40%, and ACTs of 140-200 seconds. There were no indices of oxygenator failure noted within the time frame of support. After placement of a new systemic to pulmonary shunt, the patient was removed from support and the oxygenator drained of residual blood. No evidence of fiber damage or clot formation was noted. The patient had a successful support run without complications related to cardiopulmonary support.

A technique for performing antegrade selective cerebral perfusion without interruption of forward flow or cannula relocation for pediatric aortic arch reconstruction.

New technology and advances in extracorporeal bypass circuitry and surgical techniques have drastically improved outcomes in infants with congenital heart defects. Hypothermia with circulatory arrest has fallen out of favor in many institutions over the last decade in part from data implicating even short circulatory arrest times to long-term neurologic sequelae. Implementing continuous cerebral perfusion techniques for aortic arch reconstruction is desirable in ameliorating neurologic complications because long-term survival of complex defects can be more routinely achieved. Many centers have implemented alternative means of alleviating cerebral ischemic periods by incorporating selective antegrade or retrograde cerebral perfusion techniques. The incidence of post-operative neurologic events is low when alternative cerebral perfusion techniques are used. Many techniques used to perform continuous cerebral perfusion involve brief periods of circulatory arrest, usually for perfusion cannula repositioning. Herein we describe a technique for performing continuous antegrade cerebral perfusion without a need to interrupt forward flow.

Two-stage biventricular rehabilitation for critical aortic stenosis with severe left ventricular dysfunction.

OBJECTIVES: Critical aortic valve stenosis (CAS) in the newborn is treated by balloon or surgical aortic valve intervention with nearly equal success, but the subset of patients with severe left ventricular (LV) dilation and dysfunction present a significant mortality risk. We describe a two-stage surgical management approach for those infants who represent an unusually high failure risk for either aortic valvotomy or conventional stage 1 single ventricle (Norwood) palliation because of severe LV dysfunction at the time of presentation. METHODS: A two-stage surgical palliation was undertaken consisting of surgical aortic valvotomy, bilateral pulmonary artery banding and atrial septectomy (stage 1), followed by patch closure of the atrial septal defect, ligation of the ductus arteriosus and removal of the pulmonary artery bands (stage 2) with prostaglandin infusion continued between stages to maintain right ventricular contribution to systemic perfusion via the ductus arteriosus. RESULTS: Four neonates with CAS and severely depressed LV systolic function were treated using this strategy. LV dilation resolved and systolic function improved in three patients after 2, 2 and 4 weeks, enabling stage 2. LV dysfunction did not improve in one patient who expired before conversion to biventricular circulation. Of the three who proceeded to stage 2, one infant continued to have poor biventricular diastolic function that precluded conversion, and this patient also died. The remaining two infants are now alive and well at 34 and 44 months of age. These two had the most severe LV dilation (internal dimension Z-scores of 6.9 and 7.7) and the worst systolic function (fractional shortening 4 and 10%) at presentation, and both were born prematurely (32 and 35 weeks). CONCLUSIONS: A two-stage surgical approach may improve the likelihood of survival in selected patients with CAS presenting with severely depressed LV systolic function. Relief of LV distention may have contributed to the improvement of LV function in these infants.

Newborn aortic arch reconstruction with descending aortic cannulation improves postoperative renal function.

BACKGROUND: A clinically driven transition in perfusion technique occurred at Children's Hospital and Medical Center, Omaha, Nebraska, from primarily selective cerebral perfusion bracketed by brief periods of deep hypothermic circulatory arrest to a technique of dual arterial perfusion including innominate artery and descending aortic cannulation (DAC), with continuous mildly hypothermic (>30 °C) full-flow cardiopulmonary bypass to the entire body. This study retrospectively compared outcomes in a recent cohort of neonates undergoing aortic arch reconstruction with the two techniques. METHODS: The clinical records of 142 consecutive neonates undergoing operations involving aortic arch reconstruction at a single institution between April 2004 and September 2012 were reviewed. Renal function changes were graded according to the pediatric RIFLE score (based on risk, injury, failure, loss, and end-stage kidney disease). Sixteen patients, 8 supported with selective cerebral perfusion bracketed by brief periods of deep hypothermic circulatory arrest and 8 with DAC, required immediate postoperative extracorporeal membrane oxygenation and were excluded from renal function analysis. Multivariable regression models evaluated predictors of pediatric RIFLE score. RESULTS: Patients with DAC had shorter median bypass support (113 versus 172 minutes; p < 0.001) and myocardial ischemic time (43 versus 81 minutes; p < 0.001). Patients with DAC had less median fluid gain at 24 hours (37 versus 69 mL/kg; p < 0.001), and lower incidence of acute kidney injury (5% versus 31%; p < 0.001). Fewer patients with DAC (31% versus 58%; p = 0.001) required open chest. Use of selective cerebral perfusion bracketed by brief periods of deep hypothermic circulatory arrest, single-ventricular physiology, and aortic cross-clamp time were found to be multivariable predictors of serious kidney dysfunction. CONCLUSIONS: Multisite arterial perfusion, including DAC, and maintenance of continuous mildly hypothermic full-flow cardiopulmonary bypass may offer advantages as a perfusion strategy for neonatal arch reconstruction. Prospective investigation of this technique is warranted.

Descending aortic and innominate artery cannulation for aortic arch repair with mildly hypothermic continuous cardiopulmonary bypass in infants and children.

A technique is described for exposure of the descending aorta, allowing separate arterial cannulation for perfusion of the upper and lower body during reconstruction of the aortic arch, maintaining continuous full-flow cardiopulmonary bypass to the entire body. This single technique is applicable to all aortic arch pathologies and allows an unhurried aortic reconstruction in an unobstructed field.

Cytomegalovirus reactivation and colitis after left ventricular assist device placement.

We describe two patients who developed gastrointestinal bleeding due to cytomegalovirus (CMV) colitis after placement of a HeartMate II left ventricular assist device (LVAD). We aim to raise awareness of CMV colitis as a possible cause of gastrointestinal bleeding after LVAD placement and discuss potential mechanisms for CMV reactivation and areas for future research.

"Closed-vein" technique for primary sutureless repair of anomalous pulmonary venous connection.

Deep hypothermic circulatory arrest or low-flow bypass are commonly used in primary repair of total anomalous pulmonary venous connection, or individual veins may be dissected to allow clamp or snare application, in order to provide a bloodless field for anastomosis by the direct or sutureless marsupialization technique. In the described technical modification, the marsupialization of the opened atrium to the posterior pericardium is completed before opening the pulmonary venous confluence, allowing bloodless exposure during full-flow normothermic bypass. In addition, vein branch dissection is avoided.

Cerebral oxygen saturation does not normalize until after stage 2 single ventricle palliation.

BACKGROUND: In an effort to optimize neurologic outcome, cerebral oxygen saturation (SCO2) is often measured intraoperatively and postoperatively. We hypothesized that SCO2 would be related to stage of palliation in children with single ventricle congenital heart disease. METHODS: Cerebral oxygen saturation was continuously recorded intraoperatively in 34 infants and children undergoing palliative surgery on cardiopulmonary bypass for single ventricle congenital heart defects and in a control group of 12 neonates with ductus-dependent circulation undergoing complete repair. Saturations were correlated with the patient's stage and outcome. RESULTS: Baseline SCO2 was 61% in single ventricle neonates (group P1, n = 10), 55% in neonates undergoing repair (group R), 42% in infants undergoing stage 2 palliation (group P2, n = 6), and 70% in children undergoing Fontan (group P3, n = 14). Baseline was lowest (41%) in infants undergoing interstage operations (group I, n = 4). After bypass, there was a significant improvement in SCO2 to 53% in group P2 infants (p = 0.04); there were no significant changes in the other groups. By the end of the operation, there was a significant decrease in SCO2 to 48% in group P1 (p = 0.001), with other groups unchanged from baseline. There were five perioperative deaths. Cerebral oxygen saturation at the conclusion of surgery was lower in children who died (38% versus 61%, p = 0.01). CONCLUSIONS: In children with single ventricle physiology, SCO2 decreases after initial palliation, remains low before second-stage palliation, but is normal before and after the Fontan. This has implications for perioperative mortality, neurologic injury, and potentially for interim mortality. Low postoperative SCO2 predicts perioperative mortality.

Anoxic ventilation improves systemic perfusion during extracorporeal circulation with uncontrolled systemic-to-pulmonary shunt.

Uncontrolled systemic-to-pulmonary shunt results in decreased systemic flow during extracorporeal life support (ECLS). Ligation of systemic-to-pulmonary shunts during ECLS is associated with poor outcome and is not always readily achieved. In ex vivo preparations, alveolar hypoxia results in pulmonary vasoconstriction despite normoxic pulmonary perfusate. We hypothesized that anoxic ventilation would result in reduced pulmonary shunting and increased systemic flow during ECLS in piglets with systemic-to-pulmonary shunt. Four piglets were placed on ECLS with right and left atrial drainage. A shunt was created between the bicarotid trunk and pulmonary artery, using 5-mm ePTFE tubing. Inspired oxygen was reduced to <1% for 10 minutes, then returned to room air; pH, hematocrit, temperature, ventilatory pressures, and total pump flow were maintained constant. Systemic arterial pressure and right atrial return volume and hemoglobin saturation were measured: All decreased significantly upon shunt unclamping. Anoxic ventilation caused increased systemic pressure (34 vs. 28 mm Hg, p < 0.05), flow (335 vs. 278 mL/min, p < 0.05), and systemic venous saturation (53% vs. 48%, p = 0.13) compared with room air ventilation. In conclusion, anoxic ventilation during normoxic ECLS in subjects with systemic-to-pulmonary shunts results in a significant and potentially clinically useful reduction in pulmonary shunting.