Socio-demographic parameters and non-cardiac comorbidity related to self-perceived quality of life in young adults after neonatal arterial switch operation for transposition of the great arteries.

Evaluating the relation of non-cardiac comorbidity and socio-demographic factors to physical and mental health-related quality of life (QOL) which has been partially found at elevated risk in young adults after neonatal arterial switch operation (ASO) for transposition of the great arteries (TGA). In a prospective reassessment study, results of 92 unselected young adults (22.8 ± 2.6 years) having undergone evaluation of QOL (SF-36) were related to non-cardiac comorbidity with special respect to neurologic and psychiatric comorbidity and to socio-demographic parameters. Neurologic (14%) contrary to psychiatric comorbidities (6.5%) were more frequent than in the general population. The educational level was higher, the rate of unemployment was double as high compared to the average German population. Significant inverse relations (p = 0.006 to 0.033) existed between physical health domains (physical functioning and general health perception) and non-cardiac, neurologic, and psychiatric comorbidity, as well as correlations between the latter domains and socio-economic status, educational level, and worse employment status (Spearman 0.22-0.41, p < 0.0001 to 0.036). Mental health domains (vitality, social functioning, psychical health) were significantly inversely related with neurologic and psychiatric comorbidity (p = 0.002 to 0.048) and correlated with higher educational level (Spearman 0.25, p = 0.019). Neurologic and psychiatric comorbidities and socio-demographic parameters are significant risk factors for a reduced QOL concerning physical and mental health in young adults with TGA after ASO. Standardized QOL measurement should be part of routine screening programs to detect subclinical physical, neurodevelopmental, and psychosocial comorbidity.

Long-Term Outcome Up To 40 Years after Single Patch Repair of Complete Atrioventricular Septal Defect in Infancy or Childhood.

OBJECTIVES: Patients with repaired complete atrioventricular septal defect (CAVSD) represent an increasing portion of grown-ups with congenital heart disease. For repair of CAVSD, the single-patch technique has been employed first. This technique requires division of the bridging leaflets, thus, among other issues, long-term function of the atrioventricular valves is of particular concern. METHODS: Between 1978 and 2001, 100 consecutive patients with isolated CAVSD underwent single-patch repair in our institution. Hospital mortality was 11%. Primary endpoints were clinical status, atrioventricular valve function, and freedom from reoperation in long term. Follow-up was obtained contacting the patient and/or caregiver, and the referring cardiologist. RESULTS: Eighty-three patients were eligible for long-term follow-up (21.0 ± 8.7, mean ± standard deviation [21.5; 2.1-40.0, median; min-max] years after surgical repair). Actual long-term mortality was 3.4%. Quality of life (QoL; self- or caregiver-reported in patients with Down syndrome) was excellent or good in 81%, mild congestive heart failure was present in 16%, moderate in 3.6% as estimated by New York Heart Association classification. Echocardiography revealed normal systolic left ventricular function in all cases. Regurgitation of the right atrioventricular valve was mild in 48%, mild-moderate in 3.6%, and moderate in 1.2%. The left atrioventricular valve was mildly stenotic in 15% and mild to moderately stenotic in 2%; regurgitation was mild in 54%, mild to moderate in 13%, and moderate in 15% of patients. Freedom from left atrioventricular-valve-related reoperation was 95.3, 92.7, and 89.3% after 5, 10, and 30 years, respectively. Permanent pacemaker therapy, as an immediate result of CAVSD repair (n = 7) or as a result of late-onset sick sinus syndrome (n = 5), required up to six reoperations in single patients. Freedom from pacemaker-related reoperation was 91.4, 84.4, and 51.5% after 5, 10, and 30 years, respectively. CONCLUSION: Up to 40 years after single-patch repair of CAVSD, clinical status and functional results are promising, particularly, in terms of atrioventricular valve function. Permanent pacemaker therapy results in a life-long need for surgical reinterventions.

Proximal Aortic Dilatation and Pulmonary Valve Replacement in Patients with Repaired Tetralogy of Fallot: Is There a Relationship? A Cardiac Magnetic Resonance Imaging Study.

Aortopathy is a known complication whose incidence is growing within the population of tetralogy of Fallot (TOF) patients. Its pathology and relationship with other comorbidities remain unclear. This study was designed to determine the prevalence and predictors of proximal aortic dilatation after TOF repair. We retrospectively investigated all patients who underwent follow-up cardiac magnetic resonance imaging (CMR; at least 4 years after TOF repair) between March 2004 and December 2019. The dimensions at the ascending aorta (AAo) and sinus of Valsalva (SoV) levels were measured. Aortic dilatation was defined as an internal aortic diameter that was >2 standard deviation of the previously published normal values. We included 77 patients (mean age 28.9 ± 10.5 years, 41.5% female, mean follow-up of 24.5 ± 8.1 years). AAo and SoV were dilated in 19 (24.6%) and 43 (55.8%) patients, respectively. Patients with dilated AAo and SoV were older during the corrective surgery (p < 0.001 and p = 0.004, respectively) and during CMR (p = 0.002 and 0.024, respectively) than patients without AAo and SoV dilatation. Patients of the dilated AAo group were more likely to have prior palliative shunt (p = 0.008), longer shunt duration (p = 0.005), and a higher degree of aortic valve regurgitation (AR) fraction (p < 0.001) and to undergo pulmonary (PVR) and/or aortic valve replacement (p < 0.001 and p = 0.013, respectively). PVR (p = 0.048, odds ratio = 6.413, and 95% CI = 1.013-40.619) and higher AR fraction (p = 0.031, odds ratio = 1.194, and 95% CI = 1.017-1.403) were independent predictors for AAo dilatation. Aortopathy is a common progressive complication that may require reintervention and lifelong follow-up. Our study shows that proximal aortic dilatation may be attributed to factors that increase the volume overload across the proximal aorta, including late corrective surgery and palliative shunt. We also found that PVR and higher AR fraction are independent predictors of AAo dilatation.

Myocardial Expression of Estrogen Receptor-mRNA Is Associated With Lower Markers of Post-operative Organ Damage in Young Patients With Congenital Cardiac Defect.

Background: Estrogen receptors (ERs) relate to cardio-protection in adults, but their role in younger patients is not known. We aimed to assess the myocardial expression of ERα- and ERß- mRNA in young patients with congenital cardiac disease and to analyze their putative protective role. Patients and Methods: Twenty children and young adults (seven females and 13 males) with a median age of 13.8 years (interquartile range: 12.3 years) were enrolled in this prospective study. The myocardial expression of ER-mRNA and genes involved in inflammation, growth, and stress response was assessed by real-time PCR and was correlated to post-operative (po) outcome. Results: ER-mRNA was detected in the myocardium of all patients, independently of gender and age. The expression of ER-mRNA correlated with that of mRNA coding for brain natriuretic peptide and for all cytokines tested. A higher ERα-mRNA expression correlated with lower troponin T concentrations at 24 h po (p = 0.032), higher PaO2/FiO2 ratio at 4 h po (p = 0.059), lower fluid retention at 4 h po (p = 0.048), and lower aspartate aminotransferase (AST) levels at 24 h po (p = 0.047). A higher ERß-mRNA expression was also correlated with lower fluid retention at 24 h po (p = 0.048). Patients in whom the levels of ERα- and ERß-mRNA were >P50 had lower troponin T (p = 0.003, respectively) and lower AST concentrations at 24 h po (p = 0.043, respectively) than the others. Conclusions: The expression of ERα- and ERß-mRNA is present in the myocardium of children and young adults with congenital cardiac defect and is associated with lower markers of po organ damage. This suggests that ERs may provide perioperative organ protection in this population.

Right Atrial Myocardial Remodeling in Children With Atrial Septal Defect Involves Inflammation, Growth, Fibrosis, and Apoptosis.

Introduction: Myocardial remodeling due to large atrial septum defect (ASD) is macroscopically characterized by dilation of the right-sided cardiac cavities secondary to volume overload, the cellular mechanisms of which are not yet understood. We postulated that inflammation, fibrosis, and cell death are actors of right atrial remodeling secondary to ASD. Patients and Methods: In 12 children with large ASD (median age: 63 months), expression of genes coding for proteins involved in the response to cell stress and -protection, inflammation, growth and angiogenesis, fibrosis, and apoptosis was assessed by RT-PCR in right atrial myocardial biopsies taken during cardiac surgery. The presence of cytokines in myocardial cells was confirmed by immunohistochemistry and effective apoptosis by TUNEL assay. Results: In all patients investigated, a cellular response to early mechanical stress with the initiation of early protective mechanisms, of inflammation (and its control), -growth, and -angiogenesis, of fibrosis and apoptosis was present. The apoptotic index assessed by TUNEL assay averaged 0.3%. Conclusions: In children with large ASD, macroscopic right atrial remodeling relates to cellular mechanisms involving the expression of numerous genes that either still act to protect cells and tissues but that also harm as they initiate and/or sustain inflammation, fibrosis, and cell death by apoptosis. This may contribute to long term morbidity in patients with ASD.

Aortopexy offers surgical options for a variety of pathological tracheal conditions in paediatric patients.

OBJECTIVES: Aortopexy is widely used; however, many surgeons still regard it with suspicion. To date, there are only a few large series and minimal long-term data. Against this background, our goal was to report our experience, particularly with regard to the recent expansion of indications and modification of diagnostic routine and surgical strategy. METHODS: Between 1994 and 2012, 53 patients (mean age: 1.1 years; 5 weeks-10.2 years) were operated on. Tracheomalacia after the operation for oesophageal atresia was the main indication for aortopexy (74%), followed by tracheal compression by the innominate artery (17%) and other selected indications (9%). Computed tomography angiography has emerged in recent years as the method of choice for preoperative diagnosis. Median sternotomy has replaced lateral thoracotomy, and intraoperative bronchoscopy has become the standard. RESULTS: In contrast to magnetic resonance imaging, computed tomography angiography resulted in perfect visualization of the condition. Median sternotomy and simultaneous bronchoscopy led to immediate readjustment of the aortopexy sutures in 6 patients. There were no surgical deaths or serious morbidities. The mean follow-up was 4.9 (0.3-14.9) years. Two patients with additional complex diseases died during the follow-up period. In all survivors, symptoms improved markedly or disappeared. However, we observed an increased susceptibility to lower respiratory tract infections over the long-term (32%). CONCLUSIONS: Aortopexy is effective for treating tracheomalacia of different origins and other pathological conditions as well. Preoperative computed tomography angiography offers excellent visualization of the condition. Median sternotomy and intraoperative bronchoscopy provide a combination for reliable operative and long-term results. However, many patients still have an increased susceptibility to lower respiratory tract infections.

Gene expression of cytokines, growth factors and apoptosis regulators in a neonatal model of pulmonary stenosis.

BACKGROUND: Right ventricular remodeling due to pulmonary stenosis increases morbidity in children. Its pathophysiology needs to be clarified. METHODS: Six newborn lambs underwent pulmonary arterial banding, seven sham operation. mRNA encoding for cytokines, growth factors and regulators of apoptosis was sequentially measured in myocardium and blood before and up to 12 weeks postoperatively. RESULTS: Experimental animals showed hypertrophy and fibrosis of the right ventricular myocardium, myocardial over-expression of CT-1-mRNA and higher blood concentrations of mRNA encoding for VEGF, TGF-ß, Bak and BcL-xL than controls, respectively. CONCLUSION: Neonatal pulmonary stenosis leads to myocardial hypertrophy that is associated with CT-1 gene expression and with activation of growth- and apoptosis pathways in blood cells.

Bicarotid trunk: how much is "not uncommon"?

BACKGROUND: Bicarotid trunk is the most common variation of aortic arch branching patterns. Bicarotid trunk can be a decisive factor in the surgical management of congenital heart defects. Our objective was to determine the prevalence of the bicarotid trunk among pediatric patients with congenital heart defects and to identify whether there is an association between bicarotid trunk and aortic coarctation. METHODS: From a total of 4,371 pediatric cardiac catheterizations between the years 1979 and 2010, a group of 2,033 patients were selected. Prevalence of the aortic coarctation in patients with bicarotid trunk and with a normal branching pattern was determined by evaluating the catheterization reports. In addition, associated congenital defects, vascular anomalies, and genetic syndromes were also assessed. RESULTS: Of 2,033 patients in our database, 84.8% of patients had a normal branching pattern of the aortic arch and 15.2% had a bicarotid trunk. The most frequent congenital heart defects in patients with a bicarotid trunk were ventricular septal defects, valvular pulmonary stenosis, and atrial septal defect. The most common associated vascular anomaly was the aberrant right subclavian artery. Most frequent genetic syndromes were trisomy 21, Williams syndrome, and CHARGE syndrome. CONCLUSIONS: The prevalence of bicarotid trunk of 17.6% among patients with aortic coarctation and 15.2% among the entire population studied made it not at all a rare phenomenon. Because bicarotid trunk can be a risk factor for surgery, the anatomy of the aortic arch needs to be clearly depicted and described. If ultrasonography examination cannot exclude bicarotid trunk, enhanced magnetic resonance imaging or aortic arch angiography may be necessary.

Polytetrafluoroethylene-coated pacemaker leads as surgical management of contact allergy to silicone.

We have previously reported an 18-year-old girl with a congenital heart defect who developed complete heart block after one of her corrective surgeries and who needed an epicardial pacemaker implantation. She developed contact sensitivity to silicone compounds. The problem was solved by implanting a silicone-free pacemaker system utilizing silicone-free transvenous leads. The patient was readmitted 2 years later due to lead failure. As no silicone-free epicardial leads were available, we decided to use standard silicone epicardial leads and enclose the whole system in Gore-Tex material (W.L. Gore & Associates, Flagstaff, AZ). Based on our experience we would discourage the use of silicone-free transvenous pacing leads for epicardial use.

Myocardial cardiotrophin-1 is differentially induced in congenital cardiac defects depending on hypoxemia.

AIM: Cardiotrophin-1 (CT-1) is upregulated by hypoxemia and hemodynamic overload and is characterized by potent hypertrophic and protective properties on cardiac cells. This study aimed to investigate whether CT-1 is differentially induced in the myocardium of infants with congenital cardiac defects depending on hypoxemia. METHODS & RESULTS: Infants with Tetralogy of Fallot (n = 8) or with large nonrestrictive ventricular septal defect (n = 8) undergoing corrective surgery were investigated. Expression of CT-1 was assessed at mRNA and protein levels in the right atrial and ventricular myocardium. The activation of the STAT-3 and VEGF were measured. Degradation of cardiac troponin-I served as a marker of myocardial damage. CT-1 was detected in all patients with levels negatively correlating to the arterial oxygen saturation. Higher CT-1 expression in Tetralogy of Fallot patients was associated with activation of the JAK/STAT pathway and higher cardiac troponin-I degradation. CONCLUSION: CT-1 may mediate myocardial hypertrophy and dysfunction in infants with congenital cardiac defects, particularly in those with hypoxemia.

Expression of inflammation in myocardial tissue of rabbits: comparison of two miniaturized heart-lung machines.

The majority of cases involving the surgical treatment of congenital heart disease require implementation of cardiopulmonary bypass (CPB). However, neonates and infants are particularly prone to serious complications associated with CPB as a result of capillary leak due to cardiovascular failure. These complications are related to the transfusion of foreign blood, the disproportionately large area of contact between the patient's blood and foreign material, as well as the systemic inflammatory response induced by hemolysis. To attenuate these risks, we developed a novel, highly integrative, miniaturized heart-lung machine (MiniHLM) with a static priming volume of only 102 mL. This prototype was tested in comparison with a conventional heart-lung machine (static priming volume 213 mL) using a rabbit animal model. The animals were anesthetized, sternotomized, and connected to CBP via the aorta and right atrium. The aorta was cross-clamped for 1 h. Blood samples for examination were taken at regular intervals. Biopsies of the right atrial appendage (RAA) were removed directly after initiation and after cessation of CPB. After gradual reduction of perfusion with the HLM, all rabbits were successfully weaned from CPB, and the sternum was closed. Foreign blood was not administered in all cases. After cryopreservation of the RAA tissue, de novo transcription of inflammatory cytokines was measured by means of real-time polymerase chain reaction using the comparative CT method. No significant differences in the expression of the inflammatory parameters of the myocardial tissue samples were found between the study groups.

Development of a rabbit animal model for miniaturized heart-lung machines.

The utilization of a heart-lung machine (HLM) for the correction of congenital heart defects can lead to various complications, which can culminate in multiorgan failure and death. To reduce the considerable risk of complications, we developed a miniaturized, highly integrated HLM (MiniHLM) for use in infants and children. For the purpose of testing the MiniHLM, we developed a new rabbit animal model. In all, surgery was performed on 32 rabbits. In the first series, 13 New Zealand white rabbits were placed on cardiopulmonary bypass (CPB) for 1 hour with the use of an initial version of the MiniHLM. In the second series, we operated on 19 Chinchilla Bastard rabbits using the further developed MiniHLM 02 or the Dideco Kids D100 system. While several adjustments had to be made to the operating protocol in the first series in order to lower the mortality rate, 15 of the 19 rabbits were successfully weaned from the HLM in the second series. Blood tests pertaining to hemolysis and the expression of inflammation were performed. In addition, tissue samples were taken from the right atrial auricle for the purpose of investigating the expression of inflammatory parameters. The newly developed MiniHLM prototype was tested successfully in an animal model in terms of technical function, hemolysis, and the expression of inflammation. On account of the comparability of their blood values, as well as their anatomy, Chinchilla Bastard rabbits serve as excellent models for the testing of CPB and support systems for infants and children that do not require the administration of foreign blood.

Prevention of postoperative pericardial adhesions with TachoSil.

BACKGROUND: The prevention of the pericardial adhesions largely accountable for the technical difficulty and risk of injury inherent to resternotomy continues to gain in importance with the increasing frequency of reoperations. The hemostatic sponge TachoSil (Nycomed Austria GmbH, Linz, Austria), has shown promising results in adhesion prevention in several regions of the body. This study was designed to evaluate its effectiveness in the prevention of pericardial adhesions in comparison with the Gore-Tex (W. L. Gore and Assoc, Flagstaff, AZ) surgical membrane and a control. METHODS: Twenty-four rabbits were distributed into 3 groups: TachoSil, Gore-Tex, or no barrier agent (control). After median sternotomy and pericardiotomy, the cardial surface was exposed to the aggravating effects of room air, irrigation, and gauze abrasion for one hour. A pericardial defect was created and repaired with one of the barrier agents, or left uncovered (control). Resternotomy was performed after 6 months for the evaluation of adhesion formation. RESULTS: Significantly fewer macroscopic adhesions were observed with TachoSil than Gore-Tex in all regions (p < 0.05) excluding the coronary arteries, where the difference in favor of TachoSil did not achieve significance (0.05< p-value <0.10). TachoSil also demonstrated significantly fewer retrosternal adhesions than the control, as well as a universal non-significant trend of fewer adhesions in all regions. The limited lesions present in the TachoSil group were filmy in nature and removed with blunt dissection relatively easily. No significant differences were found between Gore-Tex and the control. Microscopically, the least pronounced fibrosis formation and inflammatory reaction was detected with TachoSil. CONCLUSIONS: TachoSil is effective in the prevention of pericardial adhesions.

Direct right atrial insertion of a Hickman catheter in an 11-year-old girl.

Central venous lines are of particular importance in seriously ill children that require parenteral nutrition, chemotherapy, or other medications. The jugular or subclavian veins are ordinarily used for primary access. Alternatives include the femoral veins, the intercostal veins, and transhepatic approaches. If the use of these standard sites of placement is made impossible, due, for example, to chronic thrombosis, an alternative approach has to be found. The following report presents the case of an 11-year-old girl with short-bowel syndrome and a desperate need for parenteral nutrition. Over the course of her treatment, she developed chronic thrombosis of the jugular, subclavian, and femoral veins, as well as thrombosis of the inferior vena cava. As an alternative route for central venous access, we describe a successful direct placement of a tunnelled catheter into the right atrium via a right anterolateral thoracotomy.

A newly developed miniaturized heart-lung machine--expression of inflammation in a small animal model.

Cardiopulmonary bypass may cause severe inflammatory reactions and multiorgan failure, especially in premature and low-weight infants. This is due in part to the large area of contact with extrinsic surfaces and the essential addition of foreign blood. Thus, we developed a new miniaturized heart-lung machine (MiniHLM) with a total static priming volume of 102mL (including arterial and venous lines) and tested it in a small animal model. Seven Chinchilla Bastard rabbits were perfused with the MiniHLM (dynamic priming volume 127mL). Seven animals serving as a control were perfused using Dideco Kids and a Stöckert roller pump (modified dynamic priming volume 149mL). The rabbits were anesthetized and sternotomized, followed by cannulation of the aorta and the right atrium. The aorta was clamped for 1h. Blood for examination of inflammation (TNF-α, IL-1ß, IL-6, IL-8, and IL-10) and blood gas analysis were taken before skin incision, 5min before opening of the aorta, 15min after opening of the aorta, and 4 h after the initiation of cardiopulmonary bypass. The parameters of inflammation were expressed by means of the comparative C(T) method (ΔΔC(T) method). After gradual reduction of perfusion with the HLM, the heart was decannulated, and the sternum was closed. All rabbits were successfully weaned from cardiopulmonary bypass. Blood gas analysis was unremarkable in all cases. Foreign blood was not administered. Although statistical significance was not achieved, there was a reduced expression of inflammatory markers in the MiniHLM group. The newly developed MiniHLM prototype was tested successfully in a small animal model in terms of technical function and expression of inflammation. Upcoming tests with the industrially manufactured MiniHLM may reveal the advantages of the MiniHLM in comparison with the conventional HLM.

Prevalence of and risk factors for perioperative arrhythmias in neonates and children after cardiopulmonary bypass: continuous holter monitoring before and for three days after surgery.

BACKGROUND: A comprehensive evaluation of postoperative arrhythmias following surgery for congenital heart disease by continuous Holter monitoring has not been carried out. We aimed, firstly, to establish the time course of pre- and early postoperative arrhythmias by beat-to-beat analysis following cardiopulmonary bypass and, secondly, to examine which surgical procedures present risk factors for specific arrhythmias. METHODS: 494 consecutive patients, including 96 neonates, were studied with serial 24-hour Holter electrocardiograms before as well as uninterruptedly during the first 72 hours after surgery and prior to discharge. RESULTS: Within 24 hours of surgery 59% of the neonates and 79% of the older children developed arrhythmias. Junctional ectopic tachycardia occurred in 9% of neonates and 5% of non-neonates and ventricular tachycardia in 3% and 15%, respectively.For neonates, male sex and longer cross-clamping time independently increased the risk for arrhythmias (odds ratios 2.83 and 1.96/minute, respectively). Ventricular septal defect repair was a strong risk factor for junctional ectopic tachycardia in neonates and in older children (odds ratios 18.8 and 3.69, respectively). For infants and children, older age (odds ratio 1.01/month) and closure of atrial septal defects (odds ratio 2.68) predisposed to arrhythmias of any type. CONCLUSIONS: We present the largest cohort of neonates, infants and children that has been prospectively studied for the occurrence of arrhythmias after cardiac surgery. Postoperative arrhythmias are a frequent and transient phenomenon after cardiopulmonary bypass, provoked both by mechanical irritation of the conduction system and by humoral factors.

The Aachen MiniHLM--a miniaturized heart-lung machine for neonates with an integrated rotary blood pump.

The operation of congenital heart defects in neonates often requires the use of heart-lung machines (HLMs) to provide perfusion and oxygenation. This is prevalently followed by serious complications inter alia caused by hemodilution and extrinsic blood contact surfaces. Thus, one goal of developing a HLM for neonates is the reduction of priming volume and contact surface. The currently available systems offer reasonable priming volumes for oxygenators, reservoirs, etc. However, the necessary tubing system contains the highest volumes within the whole system. This is due to the use of roller pumps; hence, the resulting placement of the complete HLM is between 1 and 2 m away from the operating table due to connective tubing between the components. Therefore, we pursued a novel approach for a miniaturized HLM (MiniHLM) by integrating all major system components in one single device. In particular, the MiniHLM is a HLM with the rotary blood pump centrically integrated into the oxygenator and a heat exchanger integrated into the cardiotomy reservoir which is directly connected to the pump inlet. Thus, tubing is only necessary between the patient and MiniHLM. A total priming volume of 102 mL (including arterial filter and a/v line) could be achieved. To validate the overall concept and the specific design we conducted several in vitro and in vivo test series. All tests confirm the novel concept of the MiniHLM. Its low priming volume and blood contact surface may significantly reduce known complications related to cardiopulmonary bypass in neonates (e.g., inflammatory reaction and capillary leak syndrome).

The Aachen miniaturized heart-lung machine--first results in a small animal model.

Congenital heart surgery most often incorporates extracorporeal circulation. Due to foreign surface contact and the administration of foreign blood in many children, inflammatory response and hemolysis are important matters of debate. This is particularly an issue in premature and low birth-weight newborns. Taking these considerations into account, the Aachen miniaturized heart-lung machine (MiniHLM) with a total static priming volume of 102 mL (including tubing) was developed and tested in a small animal model. Fourteen female Chinchilla Bastard rabbits were operated on using two different kinds of circuits. In eight animals, a conventional HLM with Dideco Kids oxygenator and Stöckert roller pump (Sorin group, Milan, Italy) was used, and the Aachen MiniHLM was employed in six animals. Outcome parameters were hemolysis and blood gas analysis including lactate. The rabbits were anesthetized, and a standard median sternotomy was performed. The ascending aorta and the right atrium were cannulated. After initiating cardiopulmonary bypass, the aorta was cross-clamped, and cardiac arrest was induced by blood cardioplegia. Blood samples for hemolysis and blood gas analysis were drawn before, during, and after cardiopulmonary bypass. After 1 h aortic clamp time, all animals were weaned from cardiopulmonary bypass. Blood gas analysis revealed adequate oxygenation and perfusion during cardiopulmonary bypass, irrespective of the employed perfusion system. The use of the Aachen MiniHLM resulted in a statistically significant reduced decrease in fibrinogen during cardiopulmonary bypass. A trend revealing a reduced increase in free hemoglobin during bypass in the MiniHLM group could also be observed. This newly developed Aachen MiniHLM with low priming volume, reduced hemolysis, and excellent gas transfer (O(2) and CO(2)) may reduce circuit-induced complications during heart surgery in neonates.

Allergy to pacemaker silicone compounds: recognition and surgical management.

Silicone is a widely used biomaterial. Contact allergy, particularly to silicone components of pacemaker coatings, is uncommon. We present a 12-year-old girl with a history of complex congenital heart disease and acquired complete heart block excluding transvenous lead placement. Contact allergy to silicone led to multiple surgical interventions until the etiology for recurrent pacemaker wound complications was discovered. The key to diagnosis was a specific manufacturer's patch test. Complete removal of the former pacing system and placement of custom-made silicone free pacemaker components and epicardial use of silicone free transvenous leads were essential for successful therapy.