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Description / Table of Contents: Summary The use of a biochemical marker for the early identification of cerebral injury associated with the corrective surgery of congential heart disease could possibly be of great diagnostic and prognostic value. S-100, a specific glia brain cell protein, may be released into serum following brain cell damage. The aim of this study was to investigate the levels of this biochemical marker in infants before and after corrective cardiac surgery by means of cardiopulmonary bypass (CPB). 42 newborns and infants were enrolled in this study. Blood samples were collected just before and immediately after CPB, and then again 2, 24, and 48 h postoperatively. The S-100 protein serum concentrations were analyzed using a commercially-available radioimmune kit. Peak values of S-100 were found immediately after surgery and during the first 2 h postoperatively, decreasing thereafter on the 2nd postoperative day to preoperative values (p 〈0.001). Newborn showed higher peak values (0,36 μg/l) than infants (0,95 μg/l). Newborns also had higher preoperative S-100-values than infants. A significant correlation was found between the peak values of S-100 and the age of the studied infants (r =–0,74; p 〈0.0001), and the minimal rectal temperature during CPB (r =–0,67; p = 0,0004). In conclusion: elevated S-100 serum values after cardiac surgery may provide information on ostensibly incurred cerebral injury. Neonates with cyanotic congenital heart disease showed significantly higher levels of Serum S-100 protein than older infants undergoing corrective cardiac surgery beyond the neonatal period. Follow-up studies are necessary to evaluate the significant prognostic value of this biochemical marker in the brain.

Description / Table of Contents: Summary Purpose of this study was to evaluate the clinical utility of intraoperative echocardiography in the assessment of surgical repair of congenitally malformed hearts. In 235 of 508 patients who underwent cardiac surgery during a one year period transesophageal intraoperative echocardiography was performed. This was done to exclude residual ventricular septal defects or right ventricular outflow tract obstruction (n=84), to evaluate results of AV valve reconstruction (n=61), to assess ventricular function following arterial switch operation for complete transposition or in complex heart defects palliated by a Fontan-type procedure (n=50), to assess repair of left ventricular outflow obstruction (n=22) and for miscellaneous defects (n=18). Residual defects leading to immediate reoperation during the same surgical session were found in 4 patients (1.7%), minor residual defects not requiring reoperation were present in 6 patients (2.6%). In 2 patients with complete AV septal defect the left AV valves were only mildly regurgitant immediately after reconstruction but subsequent suture deshiscence required later reopoeration. Echocardiographic data were supplemented by direct pressure measurements in the ventricles and contrast injection into the left atrium. We conclude that intraoperative echocardiography can provide useful clinical informations, if its findings are interpreted in context with pressure measurements and contrast injections.

Description / Table of Contents: Summary Surgical closure of atrial septal defects can nowadays be performed without preoperative cardiac catheterization. For a transcatheter closure, however, x-ray exposure has been indispensable. We report a closure of an atrial septal defect under transesophageal echocardiography without fluoroscopy. A nine year old girl with an 11 mm atrial septal defect centrally located in the oval fossa was elected for transcatheter closure. Doppler-echocardiographically estimated Qp/Qs was 1.7:1. Oxymetric Qp/Qs was 1.6:1. After sedation with midazolam and propofol a diagnostic and interventional catheterization was performed without fluoroscopy. Under transesophageal echocardiography, the defect was sized over the wire with a 5F balloon catheter. The distance to the right pulmonary veins was 10 mm, to the coronary sinus and to the mitral valve 8 mm, respectively. Under transesophageal echocardiography, an 11 mm Amplatzer Septal Occluder was placed into the defect. Complete closure was achieved and no complications were encountered. We conclude that in selected cases with an atrial septal defect located in the oval fossa and clear-cut echocardiographic findings, an Amplatzer Septal Occluder can be safely deployed under echocardiographic guidance alone.

Description / Table of Contents: Summary Introduction: Neuropsychological morbidity following cardiac surgery of congenital heart disease (CHD) most likely considered to be due to alterations of cerebral oxygenation and hemodynamics could possibly be in part prevented by early detection by means of continous non-invasive monitoring during and after cardiac surgery. Measurement of regional cerebral blood saturation (rSO2) by near infrared spectroscopy (NIRS) mays provide qualitative information on cerebral oxygen supply and consumption. The aim of the sutdy was to investigate the relationship between the change in rSO2 and other hemodynamic parameters during the different stages of CPB in a heterogeneous group of infants and children undergoing corrective and palliative cardiac surgery by means of full flow CPB. Methods: 50 children and infants (15 infants with cyanotic CHD, median age 18 days (5 days–7 months); 15 children with cyanotic CHD, median age 4 years (1–9 years); 20 children with non-cyanotic CHD, median age 4 years (1–16 years)) undergoing surgical correction by means of full flow cardiopulmonary bypass (CPB) (120–150 ml/kg/BW) with moderate hypothermia (24±6°C) and alpha stat method were included in this study. Total circulatory arrest was used only in 3 infants. Continuous measurement of rSO2 was performed using a two channel cerebral oximeter (INVOS 31000A®, somanetics, USA). The sensor with a light source and superficial and deep received was placed in standardized localization at the left temporal head side. Hemodynamic parameters were simultaneously documented. Results: Before CPB the mean values of rSO2 in children with cyanotic congenital heart disease (CHD) were significantly lower (p=0.002) than those with non-cyanotic CHD. After onset of cardiopulmonary bypass (CPB) there was a gradual fall in rSO2 with achieved minimal values within 14–40 minutes (p〈0.01). During CPB these values of rSO2 were nearly 8–10% lower, particularly in the younger infants. After the end of CPB there was nearly subsequent restoration of these values in the older children. After rewarming and cessation of CPB rSO2 decreased up to 15% in individual patients particularly in young infants reflecting a higher O2 consumption. There relationship between the change in rSO2 and mean arterial pressure (MAP), central venous pressure (CVP), hemoglobin concentration (Hb) and temperature was in part significant in all infants during the period of monitoring. Conclusion: Change of cerebral oxygenation independent of the change in conventional hemodynamic parameters and arterial blood oxygenation suggests the necissity of separate monitoring of cerebral oxygenation and hemodynamics during and after cardiac surgery in infants and children. Further follow up studies are necessary to evaluate the neurological significance of the magnitude and duration of the decreased change in rSO2 during and after.

Description / Table of Contents: Summary Patients with long-standing cyanotic congenital heart disease (CHD) are known for impaired renal function and increased risk of developing acute renal failure after open heart surgery. We prospectively studied urinary protein concentration in 6 patients with cyanotic CHD and 4 patients with acyanotic CHD before and during a 3 day-period after surgery. Three of six patients with cyanotic CHD had preoperatively overt glomerulopathy, presenting with elevated urinary albumin concentrations in all three and elevated transferrin and immunoglobulin G concentrations in two. They progressed to acute renal failure necessitating the institution of hemodialysis 1 and 4 days after surgery. In contrast, patients with cyanotic CHD but normal urinary albumin concentrations and patients with acyanotic CHD had no overt renal impairment after cardiopulmonary bypass. Urinary excretion of albumin, immunoglobulin G, transferrin, soluble L-selectin, α1-microglobulin, and β-N-acetyl-glucosaminidase remained normal throughout the postoperative period in acyanotic CHD patients and rose slightly in cyanotic CHD patients without acute renal failure. In cyanotic CHD patients with renal failure, urinary excretion increased to more than 1000 mg/g creatinine albumin, more than 150 mg/g creatinine transferrin and more than 200 mg/g creatinine IgG 24 h after surgery. α1-microglobulin increased to more than 1000 mg/g creatinine and β-N-acetyl-glucosaminidase activity to more than 100 U/g creatinine 48 h after operation, showing additional tubular damage. Patients with CCHD and pathological proteinuria are at high risk of developing acute renal failure within few days after surgery which is heralded by excessively high urinary protein excretion.

Description / Table of Contents: Zusammenfassung Hintergrund: Inhalatives Stickmonoxyd (NO) wirkt selektiv auf den pulmonalen Gefäßwiderstand und wird bei der Therapie von Patienten mit pulmonaler Hypertension (PHT) eingesetzt, jedoch mit hohem apparativem Aufwand und nicht immer erfolgreich („non‐responder”). Wir evaluierten die Wirksamkeit von aerosolisiertem Prostazyklin (aePGI2) als therapeutische Alternative zu NO. Patienten und Methodik:Bei einer Herzkatheteruntersuchung wurde mittels NO und aePGI2 die pulmonale Vasoreagibilität von Patienten mit intrakardialen Shuntvitien und Eisenmengen‐Reaktion (Gruppe 1a, n = 30) und Patienten mit primärer und postoperativer PHT (Gruppe 1b, n = 13) untersucht; unmittelbar postoperativ wurde auf der Intensivstation aePGI2 im Vergleich zu NO bei postoperativer PHT eingesetzt (Gruppe 2, n = 6). Ergebnisse:Der Lungengefäßwiderstand konnte signifikant gesenkt werden (Gruppe 1a: von 91 % des Systemwiderstandes auf 58 % mit NO bzw. 53 % mit aePGI2; Gruppe 1b: von 20,2 Wood Units * m2 auf 13,4 bzw. 11,3; Gruppe 2: von 24,9 Wood Units * m2 auf 13,4 bzw. 11,3; Gruppe 2: von 24,9 Wood Units * m2 auf 10,5 bzw. 9,5), der Herzminutenvolumen‐Index erhöhte sich (Gruppe 1b: von 2,96 auf 3,55 und 3,96 l/min * m2, Gruppe 2: von 1,57 auf 1,89 und 2,00 l/min * m2). Schlußfolgerung: Der kurzfristige Einsatz von aePGI2zeigt eine mit NO vergleichbare selektive pulmonale Vasodilatation und erscheint bei entsprechendem umfassendem Monitoring zur akuten Behandlung von pulmonalhypertensiven Zuständen vertretbar.

Description / Table of Contents: Zusammenfassung Der interventionelle Verschluß eines Vorhofseptumdefekts gelingt nur bei, hinsichtlich der Lage und der Größe des Defekts, gut selektionierten Patienten. Alle Verschlußsysteme haben jedoch ihre speziellen Probleme, das optimale Device scheint bisher noch nicht gefunden zu sein. Seit Ende 1996 steht jedoch der von der Bauart vollständig neue Amplatzer Septal Occuder (ASO) für den ASD-Verschluß, im Rahmen einer internationalen Multicenterstudie, zur Verfügung. Der ASO ist ein selbstexpandierendes und -zentrierendes Doppelschirmchen aus Nitinoldrahtgeflecht, bei dem beide Schirmanteile mit einem zentralen Stent, dessen Durchmesser der Defektgröße entspricht, verbunden sind. In beide Schirme und den Stentanteil sind Polyesterflicken eingenäht, die den Verschluß des Loches begünstigen. Nach invasiver Größenmessung des Defekts wird der passende Doppelschirm ausgewählt und über eine lange 7- oder 8-French-Schleuse, von femoralvenös über den ASD, in den linken Vorhof geschoben. Im linken Vorhof werden der distale Anteil und der zentrale Stentanteil entfaltet und durch Zurückziehen das Loch verschlossen, so daß der Stent den ASD vollständig auskleidet. Danach wird der proximale Anteil entwickelt und der Doppelschirm freigesetzt. Eine Repositionierung des Schirms ist jederzeit problemlos durch Zurückziehen in die Schleuse möglich. Innerhalb von 4 Monaten gelang bei 29 von 31 Patienten (Alter Median 12,1 Jahre, Gewicht Median 45,0 kg) der vollständige Verschluß des ASD mit mittlerem Durchmesser von 11,0 mm (6–20 mm) ohne Komplikationen, bei einer mittleren Durchleuchtungszeit von 8,3 min (2,9–21,5 min) und Katheterverweildauer von 104,9 min. Qp:Qs lag im Mittel bei 1,5 (0,9–2,2). Während einer Beobachtungszeit von im Mittel 2,4 Monaten zeigte sich bei allen Patienten ein sicherer Sitz das ASO ohne Restshunt, Arrythmien, thrombembolische Komplikationen und ohne Beeinträchtigung der AV-Klappen-Funktion. Fazit: Bei guter Selektion bietet der Transkatheterverschluß mit dem ASO eine Möglichkeit, schnell, vollständig und unkompliziert einen ASD interventionell zu verschließen. Im Vergleich zu anderen Verschlußsystemen bietet die Methode aufgrund der vollständig unterschiedlichen Bauart entscheidende Vorteile. Letztendlich jedoch muß sich das System im Vergleich mit dan anderen Methoden bei Langzeituntersuchungen bewähren.