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Evaluate the use of coronary CTA as an initial assessment for determining Right Ventricle Dependent Coronary Circulation (RVDCC) in neonates with Pulmonary Atresia with Intact Ventricular Septum (PA IVS). Retrospective review of cases with coronary CTA and compare with available catheter angiography, pathology, surgical reports, and outcomes from Mar 2015 to May 2022. In our cohort of 16 patients, 3 were positive for RVDCC, confirmed by pathologic evaluation, and there was concordance for presence or absence of RVDCC with catheter angiography in 5 patients (4 negatives for RVDCC, 1 positive). Clinical follow up for the 8 patients that underwent RV decompression had no clinical evidence of myocardial ischemia. Our findings suggest that coronary CTA is reliable as first-line imaging for determination of RVDCC in neonates with PA IVS. These findings, if supported by further prospective study, may reserve invasive coronary angiography for cases with diagnostic uncertainty or at the time of necessary transcatheter interventions., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: Neonatal orthotopic heart transplantation was introduced in the 1980s as a treatment for complex congenital heart disease. Progress in single-ventricle palliation and biventricular correction has resulted in a decline in neonatal heart transplant volume. However, limited reports on neonatal heart transplants have demonstrated favorable outcomes. We report the long-term outcomes of patients with neonatal heart transplants at our institution spanning nearly 30 years., Methods: A retrospective analysis of neonatal heart transplants and neonates listed for transplant was performed at Children's Hospital Colorado. Primary outcomes were early and late survival. Secondary outcomes were rejection episodes, retransplantation, and development of cardiac allograft vasculopathy or post-transplant lymphoproliferative disease., Results: A total of 21 neonates underwent orthotopic heart transplantation at our institution. Among these, 10 neonates were transplanted from 1991 to 2000, 8 neonates were transplanted from 2001 to 2010, and 3 neonates were transplanted from 2011 to 2020. The average age of these patients was 17 days, and the average weight was 3.43 kg. Early survival was 95.2%. Survival at 1 and 5 years was 85.7% (confidence interval [CI], 61.9%-95.2%) and 75% (CI, 45.6%-85.5%), respectively. Of eligible patients, the 10-year and 20-year survival was 72.2% (CI, 45.1%-85.3%) and 50% (CI, 25.9%-70.1%), respectively., Conclusions: Our institution reports favorable outcomes of neonatal heart transplantation. These results should be considered within the context of outcomes for patients awaiting transplant and the limited donor availability. However, the successful nature of these procedures suggest it may be necessary to reevaluate the indications for neonatal heart transplantation, particularly where risk of mortality and morbidity with palliative or corrective surgery is high., (Copyright © 2021. Published by Elsevier Inc.)

Objectives: Turner syndrome (TS) and Marfan syndrome (MFS) are partially characterized by aortopathies with a risk of developing severe aortic dilation, stiffness and consequent dissection and aneurysm formation. The incidence of a bicuspid aortic valve (BAV) is also increased in TS. We investigated aortic stiffness in teenage TS and MFS patients and evaluated to what degree stiffness in TS patients is augmented by the presence of a BAV., Methods: Fifty-seven patients with TS (n = 37) and MFS (n = 20), as well as 22 controls with similar age and size distribution underwent evaluation of thoracic aortic stiffness using phase-contrast magnetic resonance imaging. Calculated stiffness indices including pulse wave velocity (PWV), distensibility and relative area change (RAC) were collected to characterize the ascending aorta and descending aorta. PWV was also determined to evaluate global aortic arch stiffness., Results: Patients with TS had reduced distensibility (0.43 vs 0.58%/mmHg, P < 0.05) and RAC (21 vs 29%, P < 0.01) in the ascending aorta when compared with normal controls. Similarly, patients with MFS had reduced ascending aortic distensibility (0.39 vs 0.58%/mmHg, P < 0.05) and RAC (22 vs 29%, P < 0.05). There were no differences in measured PWV in the ascending aorta. Patients with TS had significantly elevated PWV measured in the aortic arch when compared with controls (2.7 vs 1.9 m/s, P < 0.05). Patients with MFS had more prominent elevation in aortic arch PWV (4.2 vs 1.9 m/s, P < 0.01). The descending aortas had decreased distensibility (0.36 vs 0.55%/mmHg, P < 0.05) and RAC (18 vs 25%, P < 0.01) only in MFS patients. Additionally, 18 TS patients with a BAV were compared with 19 TS patients with a trileaflet aortic valve, without significant differences observed in any of the considered stiffness indices., Conclusions: TS and MFS teenage patients display evidence of increased aortic stiffness. In TS patients, this is focused in the ascending aorta and is independent of the presence of a BAV. MFS patients display a generalized reduction in compliance of the entire aorta.

Centrifugal blood pumps are being increasingly utilized in children supported with extracorporeal membrane oxygenation (ECMO). Our aim was to determine if survival and ECMO-related morbidities in children supported with venoarterial (VA) ECMO differed by blood pump type.Children aged less than 18 years who underwent VA ECMO support from 2007 to 2009 and reported to the Extracorporeal Life Support Organization registry were propensity score matched (Greedy 1:1 matching) using pre-ECMO characteristics.A total of 2,656 (centrifugal = 2,231, roller = 425) patients were identified and 548 patients (274 per pump type) were included in the propensity score-matched cohort. Children supported with centrifugal pumps had increased odds of hemolysis (odds ratio [OR], 4.03 95% confidence interval [CI], 2.37-6.87), hyperbilirubinemia (OR, 5.48; 95% CI, 2.62-11.49), need for inotropic support during ECMO (OR, 1.54; 95% CI, 1.09-2.17), metabolic alkalosis (blood pH > 7.6) during ECMO (OR, 3.13; 95% CI, 1.49-6.54), and acute renal failure (OR, 1.61; 95% CI, 1.10-2.39). Survival to hospital discharge did not differ by pump type.In a propensity score-matched cohort of pediatric ECMO patients, children supported with centrifugal pumps had increased odds of ECMO-related complications. There was no difference in survival between groups.

Background: Advances in centrifugal blood pump technology have led to increased use of centrifugal pumps in extracorporeal membrane oxygenation (ECMO) circuits. Their efficacy and safety in critically ill neonates remains unknown. Blood cell trauma leading to hemolysis may result in end-organ injury in critically ill neonates receiving centrifugal pump ECMO. We hypothesized that neonates undergoing ECMO support using centrifugal pumps were at increased odds of hemolysis and subsequent end-organ injury., Methods: Children 30 days of age or younger who received support with venoarterial ECMO and were reported to the Extracorporeal Life Support Registry during 2007 to 2009 underwent propensity score matching (Greedy matching 1:1) using pre-ECMO support characteristics., Results: A total of 1,592 neonates receiving ECMO (centrifugal pump = 163 and roller pump = 1,492) were identified. Significant differences in demographic, presupport, and cannulation variables were present before matching. One hundred seventy-six neonates who were supported using either centrifugal (n = 88) or roller pumps (n = 88) were matched using propensity scoring. No significant differences in demographic, presupport, or cannulation variables were present after matching. Neonates undergoing support using centrifugal pumps had increased odds of hemolysis (odds ratio [OR], 7.7 [2.8-21.2]), hyperbilirubinemia (OR, 20.8 [2.7-160.4]), hypertension (OR, 3.2 [1.3-8.0]), and acute renal failure (OR, 2.4 [1.1-5.6]). Survival to discharge was not different between pump types., Conclusions: Use of ECMO using centrifugal pumps is associated with increased odds of hemolysis that likely contributes to other end-organ injury. Research into the optimal use of centrifugal pumps and strategies to prevent support-related complications need to be investigated., (Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

This review, the second of two parts, describes the repair of aortic arch anomalies, left-to-right shunts, valvular disease, tetralogy of Fallot, and truncus arteriosus. Cardiac transplantation is also discussed. Advances in the surgical management of congenital heart disease have led to improved patient survival and quality of life. Improvements in technology in computed tomography and magnetic resonance imaging have resulted in increasing utilization of cross-sectional imaging in these patients. Perioperative care necessitates that radiologists have a basic understanding of the surgical treatment and the resultant postoperative anatomy. Because many patients with treated congenital heart disease are being followed up into the 4th and 5th decades of life, this is information that will fall within the domain of all radiologists who interpret cross-sectional images of the thorax., ((c) RSNA, 2008.)

Advances in the surgical management of congenital heart disease have led to enhanced patient survival and quality of life. Improvements in technology in computed tomography and magnetic resonance imaging have resulted in increasing use of cross-sectional imaging in these patients. Perioperative care in these patients requires that radiologists have an understanding of the surgical treatment and the resultant postoperative anatomy. Because many of these patients with treated congenital heart disease are being followed into the 4th and 5th decades of life, this is information that will fall within the domain of the radiologist who deals with adults. This review, which is presented in two parts, covers the major surgical procedures used for the treatment of congenital heart disease, and will be presented in two parts. In part 1, median sternotomy and its complications, palliative procedures, and complex repairs are discussed., ((c) RSNA, 2008.)

Coronary artery fistulas (CAF) are rare abnormalities that can be symptomatic or asymptomatic. Most drain into the right ventricle or pulmonary artery, though a variety of other drainage sites have been reported. We report the results of the surgical closure of a symptomatic left coronary-to-pulmonary artery fistula associated with a giant 10-cm aneurysm and discuss the management of coronary artery fistulas.

Extracorporeal membrane oxygenation (ECMO) has been found effective in supporting infants with severe cardiac dysfunction following open heart surgery. Centers using this mode of support can also, in instances of single ventricle morphology, consider the option of eliminating the oxygenator from the standard ECMO set-up and thereby provide roller pump ventricular assist. In these cases, the infant's own lungs can provide excellent oxygenation simply by leaving the aortopulmonary shunt open. Since ventricular support ensures maintenance of normal cardiac output, manipulation of pulmonary versus systemic flows is not necessary. This configuration retains the safety features of the ECMO system and is easily staffed by the ECMO support personnel. There may be several benefits to employing this type of management.

Background: Patch enlargement of severe branch pulmonary artery stenosis (PAS) or pulmonary vein ostial stenosis (PVS) can be technically challenging. Recurrences are common and exposure may require long periods of cardiopulmonary bypass (CPB)., Methods: Since 1993, we performed 31 procedures on 27 patients with endovascular stents placed intraoperatively under direct surgical vision: 22 patients with tight PAS and 5 patients with PVS. Selection for intraoperative (vs catheterization laboratory) stent placement was prompted by: (1) the need for a concomitant cardiac surgical procedure (16 cases); (2) limited vascular access for catheterization laboratory stent placement (11 cases); or (3) "rescue" of patients with complications after attempted placement of stents (4 cases)., Results: In this group of very complex and challenging patients there were 5 hospital deaths (hospital survival, 81%). Follow-up of survivors has ranged from 1 month to 7 years (mean 2.8 +/- 1.7 years). There have been 3 late deaths (late "series" survival, 70%). No complication or death was related to stent placement. Surviving patients have had significant clinical improvement. Mean pulmonary gradient (postoperative vs preoperative echo) has fallen in all survivors and has decreased from a mean of 66 mm Hg preoperatively to 28 mm Hg postoperatively (p = 0.01). All pulmonary arteries are appreciably enlarged and will be easier to deal with at a later date if necessary. One patient (DORV, HLHS ) with pulmonary vein stents has gone on to a successful Glenn procedure. The other two surviving patients with PV stents have occlusion of their proximal PVs on follow-up catheterization; thus only 1 of 5 patients with stents for PVS has had a successful outcome. Four patients have had repeat surgery. Stents have produced no impediment to subsequent surgical procedures, and the pulmonary arteries were easy to work with., Conclusions: Intraoperative stenting provides an attractive option for "rehabilitation" of pulmonary vessels. Direct vision insertion on CPB is extremely quick and immediately effective, limiting the CPB exposure required to treat this problem. Once stented, vessels remain open and are amenable to future surgical intervention as necessary. Outcome is better for patients with PAS versus those with PVS.

Background: The cryopreserved homograft has emerged as the pulmonary conduit of choice for the repair of many congenital heart defects. It is also used for pulmonary valve replacement in the Ross procedure. Because of a wide range of patient ages and diagnoses, the risk of homograft failure may vary., Methods: We reviewed 185 consecutive pulmonary position implants performed between September 1985 and January 1999. We examined three age groups: patients less than 1 year of age (n = 53), patients 1 to 10 years of age (n = 46), and patients more than 10 years of age (n = 86)., Results: Five-year Kaplan-Meier homograft survival was 25%, 61%, and 81% for the groups, respectively (p < 0.02). Smaller homograft size, younger patient age, and truncus arteriosus were risk factors for homograft failure in univariate analysis (p < 0.05). Smaller homograft size was the only predictor for homograft failure in multivariate analysis (p < 0.001). Twenty of 99 implants in patients less than 10 years old underwent transcatheter intervention. The 3-year Kaplan-Meier implant survival of this group (79%) was not different from those who did not undergo intervention (77%, p = 0.84). Survival of aortic and pulmonary homografts in patients less than 10 years of age was not different (p = 0.35). Ross procedure implants appear to have optimal survival (94%) at 5 years. Non-Ross implants in patients more than 10 years of age have 76% 5-year Kaplan-Meier survival, which is not different from Ross patients (p = 0.33)., Conclusions: Small homografts have limited durability. Aortic homografts perform as well as pulmonary homografts in young patients. Once patients receive an "adult-size" homograft, at approximately 10 years of age, risk for implant failure approximates that of patients undergoing the Ross procedure. Transcatheter interventions, when indicated, may prolong homograft life.

Objective: The purpose of this study was to determine the effects of a leukocyte-depleting filter on cerebral and renal recovery after deep hypothermic circulatory arrest., Methods: Sixteen 1-week-old piglets underwent cardiopulmonary bypass, were cooled to 18 degrees C, and underwent 60 minutes of circulatory arrest, followed by 60 minutes of reperfusion and rewarming. Global and regional cerebral blood flow, cerebral oxygen metabolism, and renal blood flow were determined before cardiopulmonary bypass, after the institution of cardiopulmonary bypass, and at 1 hour of deep hypothermic circulatory arrest. In the study group (n = 8 piglets), a leukocyte-depleting arterial blood filter was placed in the arterial side of the cardiopulmonary bypass circuit., Results: With cardiopulmonary bypass, no detectable change occurred in the cerebral blood flow, cerebral oxygen metabolism, and renal blood flow in either group, compared with before cardiopulmonary bypass. In control animals, after deep hypothermic circulatory arrest, blood flow was reduced to all regions of the brain (P <.004) and the kidneys (P =.02), compared with before deep hypothermic circulatory arrest. Cerebral oxygen metabolism was also significantly reduced to 60.1% +/- 11.3% of the value before deep hypothermic circulatory arrest (P =.001). In the leukocyte-depleting filter group, the regional cerebral blood flow after deep hypothermic circulatory arrest was reduced, compared with the value before deep hypothermic circulatory arrest (P <.01). Percentage recovery of cerebral blood flow was higher in the leukocyte filter group than in the control animals in all regions but not significantly so (P >.1). The cerebral oxygen metabolism fell to 66.0% +/- 22.3% of the level before deep hypothermic circulatory arrest, which was greater than the recovery in the control animals but not significantly so (P =.5). After deep hypothermic circulatory arrest, the renal blood flow fell to 81.0% +/- 29.5% of the value before deep hypothermic circulatory arrest (P =.06). Improvement in renal blood flow in the leukocyte filter group was not significantly greater than the recovery to 70.2% +/- 26.3% in control animals (P =.47)., Conclusions: After a period of deep hypothermic circulatory arrest, there is a significant reduction in cerebral blood flow, cerebral oxygen metabolism, and renal blood flow. Leukocyte depletion with an in-line arterial filter does not appear to significantly improve these findings in the neonatal piglet.

Background: After repair of complex congenital heart defects in infants and children, postcardiotomy cardiac failure requiring temporary circulatory support can occur. This is usually accomplished with the use of extracorporeal membrane oxygenation (ECMO). ECMO management of patients with single-ventricle physiology and aorto-pulmonary shunts can be particularly challenging. We retrospectively reviewed our experience with postcardiotomy support with particular attention to those children with single-ventricle palliation., Methods: Thirty-five consecutive children (age 1 to 820 days, median 19 days) out of 1,020 patients (3.4%) required mechanical support (ECMO) after repair of congenital cardiac lesions from February 1994 to April 1999. Twenty-five patients underwent two ventricle repairs and 10 patients had single-ventricle palliation. Various parameters analyzed included strategies of shunt management, presence of presupport cardiac arrest, and timing of support initiation., Results: Overall hospital survival for these 35 patients was 61%. There were four additional late deaths. Hospital survival was the same for those patients in whom support was initiated for failure to wean from cardiopulmonary bypass in the operating room versus those patients in whom support was initiated after successful separation from cardiopulmonary bypass (6 of 10 vs 15 of 25 or 60% survival). In those patients with shunt-dependent pulmonary circulation, survival was significantly improved in those patients in which the aorto-pulmonary shunt was left open (4 of 5 with open shunt vs 0 of 4 with occluded shunt (p = 0.048)., Conclusions: The ability to readily implement postcardiotomy support is vital to the management of children with complex congenital cardiac disease. Overall survival can be quite satisfactory if support is employed in a rational and expedient manner. In patients with single-ventricle physiology and aorto-pulmonary shunts, leaving the shunt open during the period of support can result in markedly improved outcomes.

Background: Panel-reactive antibody (PRA) is used to estimate the degree of humoral sensitization in the recipient before transplantation. Although pretransplant sensitization is associated with increased complications in other solid organ transplant recipients, less is known about the outcome of sensitized lung transplant recipients. Therefore, we sought to determine the impact of elevated pretransplant PRA on clinical outcomes after lung transplantation., Methods: The records of the first 200 lung transplant operations performed at Duke University Medical Center were reviewed. The outcomes of sensitized patients, PRA greater than 10% before transplantation (n = 18), were compared with the outcomes of nonsensitized patients., Results: Sensitized patients experienced a significantly greater number of median ventilator days posttransplant (9 +/- 8) as compared with nonsensitized recipients (1 +/- 11; p = 0.0008). There were no significant differences between the number of episodes of acute rejection; however, there was a significantly increased incidence of bronchiolitis obliterans syndrome occurring in untreated sensitized recipients (56%) versus nonsensitized (23%; p = 0.044). In addition, there was a trend towards decreased survival in the sensitized recipients, with a 2-year survival of 58% in sensitized recipients as compared with 73% in the nonsensitized patients (p = 0.31)., Conclusions: Sensitized lung transplant recipients experience more acute and chronic complications after transplantation. These patients probably warrant alternative management strategies.

The extant nomenclature for transposition of the great arteries (TGA) is reviewed for the purposes of establishing a unified reporting system. The subject was debated and reviewed by members of the STS-Congenital Heart Surgery Database Committee and representatives from the European Association for Cardiothoracic Surgery. All efforts were made to include relevant nomenclature categories including synonyms where appropriate. The general categories of TGA are: TGA with intact ventricular septum, TGA with ventricular septal defect (VSD) and TGA with VSD and left ventricular outflow tract obstruction (LVOTO). A comprehensive database set is presented which is based on a hierarchical scheme. Data are entered at various levels of complexity and detail that can be determined by the clinician. A detailed hierarchical system is described herein for classification of the coronary artery anatomy associated with TGA. These data can lay the foundation for comprehensive risk stratification analyses. A minimum database set is also presented which will allow for data sharing and would lend itself to basic interpretation of trends.

The extant nomenclature for pulmonary venous anomalies is reviewed for the purpose of establishing a unified reporting system. The subject was debated and reviewed by members of the STS-Congenital Heart Surgery Database Committee and representatives from the European Association for Cardiothoracic Surgery. All efforts were made to include all relevant nomenclature categories using synonyms where appropriate. The basis for classification are the prenatal errors of embryologic development. The major categories include: partially anomalous pulmonary venous connection, totally anomalous pulmonary venous connection, atresia of the common pulmonary vein, cor triatriatum, and stenosis or abnormal number of pulmonary veins. A comprehensive database set is presented that is based on a hierarchical scheme. Data are entered at various levels of complexity and detail that can be determined by the clinician. These data can lay the foundation for comprehensive risk stratification analyses. A minimum database set is also presented that will allow for data sharing and would lend itself to basic interpretation of trends. Potential diagnostic-related risk factors are presented.

Objective: The aim of this study was to assess the effects of preoperative high dose methylprednisolone on cerebral recovery following a period of deep hypothermic circulatory arrest (DHCA)., Methods: Sixteen 1-week-old piglets were randomized to placebo (n=8), or 30 mg/kg intramuscular methylprednisolone sodium succinate (MPRED) given at 8 and 2 h before induction of anaesthesia. All piglets underwent cardiopulmonary bypass, cooling to 18 degrees C, 60 min of circulatory arrest followed by 60 min of reperfusion and rewarming. The radiolabelled microsphere method was used to determine the global and regional cerebral blood flow (CBF) and cerebral oxygen metabolism (CMRO(2)) at baseline before DHCA and after 60 min of reperfusion., Results: In controls, mean global CBF (+/-1 standard error) before DHCA was 53.7+/-2.4 ml/100 g per min and fell to 23.8+/-1.2 ml/100 g per min following DHCA (P<0.0001). This represents a post-DHCA recovery to 45.1+/-3.3% of the pre-DHCA value. In the MPRED group recovery of global CBF post-DHCA was significantly higher at 63.6+/-5.2% of the pre-DHCA value (P=0.009). The regional recovery of CBF in the cerebellum, brainstem and basal ganglia was 80, 75 and 69% of pre-DHCA values in the MPRED group respectively compared to 66, 60 and 55% in controls (P<0.05). Global CMRO(2) in controls fell from 3.9+/-0.2 ml/100 g per min before to 2. 3+/-0.2 ml/100 g per min after DHCA (P=0.0001). This represents a post-DHCA recovery to 58.6+/-4.4% of the pre-DHCA value. In the MPRED group, however, recovery of global CMRO(2) post-DHCA was significantly higher at 77.9+/-7.1% of the pre-DHCA value (P=0.04)., Conclusions: Treatment with high dose methylprednisolone at 8 and 2 h preoperatively attenuates the normal cerebral response to a period of deep hypothermic ischaemia. This technique may therefore offer a safe and inexpensive strategy for cerebral protection during repair of congenital heart defects with the use of DHCA.

Objective: The aim of this study was to assess the role of reactive oxygen species in the impairment of cerebral recovery that follows deep hypothermic circulatory arrest., Methods: Twelve 1-week-old piglets were randomized to placebo (control group; n = 6) or 100 mg x kg(-1) intravenous alpha-phenyl-tert -butyl nitrone, a free radical spin trap (PBN group; n = 6). All piglets underwent cardiopulmonary bypass, cooling to 18 degrees C, 60 minutes of circulatory arrest followed by 60 minutes of reperfusion, and rewarming. Cerebral blood flow and metabolism were determined at baseline before deep hypothermic circulatory arrest and after 60 minutes of reperfusion., Results: In control animals, mean global cerebral blood flow (+/- 1 standard error) before circulatory arrest was 48.4 +/- 3.6 mL x 100 g(-1) x min(-1) and fell to 25.1 +/- 3.6 mL x 100 g(-1) x min(-1) after circulatory arrest (P =.001). Global cerebral metabolism fell from 3.5 +/- 0.2 mL x 100 g(-1) x min(-1) before arrest to 2.2 +/- 0.2 mL x 100 g(-1) x min(-1) after circulatory arrest (P =.0002). In the PBN group after circulatory arrest, the mean global cerebral blood flow and metabolism of 37.2 +/- 4.9 and 3.6 +/- 0.5 mL. 100 g(-1). min(-1), respectively, were significantly higher than in the control group (P <.05). Recovery of cerebral blood flow in the PBN group was 78% of pre-arrest level compared with 52% in the control group (P =.002). Global cerebral metabolism after circulatory arrest was 100% of the pre-arrest value compared with 61% in the control group (P =.01). Regional recovery of cerebral metabolism in the cerebellum, brain stem, and basal ganglia was 131%, 130%, and 115%, respectively, of pre-arrest values in the PBN group compared with 85%, 78%, and 70% in the control group (P <.04)., Conclusions: Reactive oxygen species contribute to the impairment of cerebral recovery that follows deep hypothermic circulatory arrest. The use of alpha-phenyl-tert -butyl nitrone before the arrest period attenuates the normal response to ischemia and improves recovery by affording protection from free radical-mediated damage.

Background: The aim of this study was to determine the effects of antagonism of platelet-activating factor receptors on cerebral recovery after deep hypothermic circulatory arrest (DHCA)., Methods: Fourteen 1-week-old piglets were randomly assigned to either placebo (n = 7), or 10 mg/kg intravenous ginkgolide B (BN52021), a naturally occurring platelet-activating factor receptor antagonist. All piglets had cardiopulmonary bypass, cooling to 18 degrees C, 60 minutes of circulatory arrest followed by 60 minutes of reperfusion and rewarming. Global and regional cerebral blood flow, cerebral oxygen metabolism and renal blood flow were determined at baseline before DHCA and after 60 minutes of reperfusion., Results: Blood flow was significantly reduced in all regions of the brain (p < 0.001) and the kidneys (p = 0.02) after DHCA in control animals. Cerebral oxygen metabolism was also significantly reduced after DHCA to 59.2% +/- 3.2% of the pre-DHCA value (p = 0.0003). In the ginkgolide B group, recovery of global cerebral blood flow to 60.4% +/- 2.8% of pre-DHCA level and of global cerebral oxygen metabolism to 77.1% +/- 5.8% of pre-DHCA value were significantly higher than the recovery in the control group (p < 0.02). Regional recovery of cerebral blood flow and oxygen metabolism in the gingkolide B group was greatest in the cerebellum and brainstem. Renal blood flow did not decrease significantly after DHCA in the gingkolide B group (p = 0.23)., Conclusions: These results suggest that production of platelet-activating factor is increased in the brain after DHCA. Platelet-activating factor receptor antagonism with ginkgolide B before the circulatory arrest period can significantly improve recovery of cerebral blood flow and oxygen metabolism and renal blood flow after DHCA.

Background: Procoagulant activity after cardiopulmonary bypass (CPB) in infants may predispose to thrombotic and bleeding complications. The induction of tissue factor and prothrombinase activity on endothelial cell membranes is a primary step in the activation of the extrinsic clotting cascade. The purpose of this study is to characterize the fibrinolytic and endothelial procoagulant state in infants undergoing congenital cardiac repairs with and without CPB., Methods: Fourteen infants (aged 1 to 12 weeks) underwent repair of congenital cardiac defects. Two patients had closed procedures (controls) and 12 had open cardiac procedures. Serum samples were taken before and after CPB, 1, 4, and 24 hours after CPB. Tissue plasminogen activator, plasminogen activator inhibitor-1, interleukin-1beta, interleukin-6, plasma tissue factor, and factor V levels were measured. Human umbilical vein endothelial cell cultures were incubated with serum taken from the above time points and assayed for induction of tissue factor and prothrombinase activity., Results: Control patients had no change from preoperative values in any of the parameters examined. In experimental patients, tissue plasminogen activator levels peaked at 1 hour after CPB and then decreased to normal by 24 hours. Plasminogen activator inhibitor-1 levels peaked at 4 hours after CPB and returned to baseline by 24 hours. The plasma of all patients had no intrinsic tissue factor activity. Induction of tissue factor activity on umbilical vein endothelial cells peaked immediately and again at 24 hours, whereas prothrombinase activity peaked early and stayed elevated. Serum factor V levels were significantly reduced after CPB, but returned to near baseline levels by 24 hours., Conclusions: Cardiopulmonary bypass is associated with derangement of the coagulation and fibrinolytic systems in infants. The serum of these patients promotes the induction of endothelial procoagulant activity, suggesting that there may be a hypercoagulable state in the postbypass period.

Background: Deep hypothermic circulatory arrest (DHCA) has been shown to cause impairment in recovery of cerebral blood flow (CBF) and cerebral metabolism (CMRO2) proportional to the duration of the DHCA period. This effect on CMRO2 may be a marker for brain injury, because CMRO2 recovers normally after cardiopulmonary bypass (CPB) when DHCA is not used. The aim of this study was to investigate the effects of intermittent perfusion during DHCA on the recovery of CMRO2 after CPB and to correlate these findings with electron microscopy (EM) of the cerebral microcirculatory bed., Methods: Fifteen neonatal piglets were placed on CPB and cooled to 18 degrees C. Each animal then underwent either: (1) 60 minute continuous CPB (control), (2) 60 minute uninterrupted DHCA (UI-DHCA), or (3) 60 minute DHCA with intermittent perfusion (1 minute every 15 minutes) (I-DHCA). All animals were then rewarmed and weaned from CPB. Measurements of CBF and CMRO2 were taken before and after CPB. A further 9 animals underwent CPB without DHCA (2 animals) or with DHCA (7 animals), under various conditions of arterial blood gas management, intermittent perfusion, and reperfusion time., Results: UI-DHCA resulted in significant impairment to recovery of CMRO2 after CPB (p < 0.05). Regardless of the blood gas strategy used, the EM after UI-DHCA revealed extensive damage characterized by perivascular intracellular and organelle edema, and vascular collapse. I-DHCA, on the other hand, produced a pattern of normal CMRO2 recovery identical to controls, and the EM was normal for both these groups., Conclusions: Intermittent perfusion during DHCA is clinically practical and results in normal cerebral metabolic and ultrastructural recovery. Furthermore, the correlation between brain structure and CMRO2 suggests that monitoring CMRO2 during the operation may be an outstanding way to investigate new strategies for neuroprotection designed to reduce cerebral damage in children undergoing correction of congenital cardiac defects.

Background: Pulmonary hypertension and lung injury secondary to cardiopulmonary bypass (CPB) are probably caused by a combination of ischemia and inflammation. This study was undertaken to investigate the potential ischemic effects of cessation of pulmonary arterial flow during CPB on pulmonary injury., Methods: Twenty neonatal piglets (2.5 to 3.1 kg) were randomly assigned to two groups. Group A (n = 10) underwent 90 minutes of CPB at full flow (100 mL x kg(-1) x min(-1)) and clamping of the main pulmonary artery (PA). Group B (n = 10) underwent 90 minutes of partial CPB (66 mL x kg(-1) x min(-1)) with continued mechanical ventilation and without clamping of the PA. All hearts were instrumented with micromanometers and a PA ultrasonic flow probe. Endothelial function was assessed by measuring endothelial-dependent relaxation (measured by change in pulmonary vascular resistance after PA infusion of acetylcholine) and endothelial-independent relaxation (measured by change in pulmonary vascular resistance after ventilator infusion of nitric oxide and PA infusion of sodium nitroprusside)., Results: All groups exhibited signs of pulmonary injury after CPB as evidenced by significantly increased pulmonary vascular resistance, increased alveolar-arterial O2 gradients, and decreased pulmonary compliance (p<0.05); however, pulmonary injury was significantly worse in group A (p<0.05)., Conclusions: This study suggests that although exposure to CPB alone is enough to cause pulmonary injury, cessation of PA flow during CPB contributes significantly to this pulmonary dysfunction.