1-year left ventricular assist device (LVAD) experience as bridge to heart transplantation in an infant with Bland-White-Garland syndrome

Left ventricular assist device (LVAD) implantation has become an established therapy in adults as well as in children as a bridge to heart transplantation or to aid myocardial recovery. We describe the first case worldwide of an infant suffering from Bland-White-Garland syndrome successfully treated with a left ventricular assist device (Berlin Heart(R); Excor(R) Pediatric) as a bridge to heart transplantation for a period of more than one year.

[Atrial flutter after orthotopic heart transplantation due to recipient-to-donor transatrial conduction]

A few weeks after orthotopic heart transplantation, a male adolescent developed atrial arrhythmias of the donor heart due to an atypical recipient atrial flutter with a recipient-to-donor transatrial conduction resulting in an absolute arrhythmia. Under medication with propafenone, the atrial flutter of the donor heart could be terminated with cardioversion.

Congenital aortic regurgitation due to absent aortic cusps and high-degree mitral stenosis

Congenital absence of aortic cusps leads to severe aortic regurgitation. We present a newborn with this rare entity with extreme mitral stenosis. Hemodynamic features were those of hypoplastic left heart syndrome. Surgical management consisted of initial modified Norwood procedure followed by orthotopic heart transplantation.

Mycotic cerebral vasculitis in a paediatric cardiac transplant patient excludes misadventure

We present the case of a 10-year-old girl with cardiomyopathy who received a heart transplant. Due to organ rejection, the dosage of immunosuppressive agents was increased postoperatively. The patient complained of intermittent headaches in the following days and developed a haemorrhagic necrosis of the left thalamus. A week later, an oral dose of cyclosporin A was accidentally given intravenously, and 2 weeks later a recurrent subarachnoid haemorrhage of unknown origin was diagnosed. The clinical course was then characterised by progressive deterioration resulting in coma, fluctuating brain stem symptoms and the development of a massive cerebral oedema with subsequent brain death. A coroner's autopsy was instigated to investigate a claim of medical misadventure. Neuropathological investigations found a focal infiltration of fungal hyphae in the left posterior cerebral artery resulting in necrosis of the vascular wall and thus explaining the source of the recurrent subarachnoid haemorrhage which eventually resulted in the girl's death. Medical misadventure due to the administration of cyclosporin was not directly responsible for the death of this patient. This case illustrates that it is of paramount importance to copiously sample and investigate the basal cerebral arteries in cases of subarachnoid haemorrhage of unknown origin, in particular in a medico-legal context.

Interaction of fibrinolysis and prothrombotic risk factors in neonates, infants and children with and without thromboembolism and underlying cardiac disease. a prospective study

To evaluate the role of plasminogen activator inhibitor-1 (PAI-1) and tissue-type plasminogen activator (t-PA) in children with an estimated risk of vascular occlusion reported to range from 7% to 16%, we conducted a prospective study in infants and children with underlying cardiac disease. One hundred and twenty-five children (neonate - 16 years) were investigated. In 9 infants out of the 125 children vascular occlusion occurred, closely related to cardiac catheterisation and arterial or venous lines during major cardiac surgery. Six of the nine neonates and infants with (n=6) and without (n=3) prothrombotic risk factors showed evidence of a basically impaired fibrinolytic system. Five of the nine infants showed increased PAI-1 clearly correlated to the 4G/4G genotype of the plasminogen activator-1 promoter polymorphism along with elevated t-PA concentration before the first diagnostic cardiac catheterisation was performed. One infant presented with increased t-PA concentration only. Five of the six children with reduced fibrinolytic capacity had further prothrombotic risk factors.

CONCLUSION

Data of this study indicate that neonates and infants with underlying cardiac disease and basically increased PAI-1 due to the 4G/4G variant of the PAI-1 promoter polymorphism along with elevated t-PA levels in combination with further prothrombotic risk factors are at high risk of developing early thromboembolism during cardiac catheterisation.

Cardiac leiomyosarcoma of the right atrium in a teenager: unusual manifestation with a lifetime history of atrial ectopic tachycardia

A 16-year-old girl presented with atrial fibrillation. Transesophageal echocardiography revealed a right atrial leiomyosarcoma. Her past medical history was remarkable for incessant atrial ectopic tachycardia (AET) beginning in early infancy and continuing throughout childhood and adolescence that was refractive to medical and nonpharmacological treatment. After combined surgical and medical therapy, normal sinus rhythm was restored and the patient is currently in complete remission with no recurrent symptoms or atrial arrhythmias at 31 months after surgery and 23 months after the discontinuation of chemotherapy. Atrial tachycardia may be the first, and for prolonged periods, the only manifestation of a cardiac tumor and should prompt thorough investigation of its underlying morphological substrate.

Neonatal mechanical bridging to total orthotopic heart transplantation

BACKGROUND

Until recently, newborns with medically intractable cardiac failure caused by congenital malformations were mostly doomed to death because of the severity of the disease, which precludes a palliative operation, or because of fatal deterioration before availability of a suitable donor heart.

METHODS

The recently developed paracorporeal pneumatically driven Medos HIA ventricular assist device offers a therapeutic option for these small infants because it is manufactured in various sizes and is even suitable for cardiac assistance in neonates with a body surface area less than 0.3 m2.

RESULTS

We report our initial experience with this device, which we used for univentricular bridging to total orthotopic cardiac transplantation in 3 infants. The device was inserted to support the left ventricle in two instances and to support the right heart in one. Successful bridging to transplantation was achieved in 2 infants for periods of 2 and 7 weeks.

CONCLUSIONS

Our experience demonstrates the feasibility of univentricular mechanical support followed by successful cardiac transplantation in infants and newborns.

[A rare combination of partial trisomy 9 with pulmonary atresia]

We report of an previously unpublished combination of partial trisomy 9 and a membranous pulmonary atresia with a large conotruncal ventricular septal defect. The dystrophic female, term newborn presented after delivery with microcephaly, prominent nose and several other facial and skeletal deformities. The echocardiography and angiography showed a membranous pulmonary atresia with ventricular septal defect. Chromosomal analysis revealed a partial trisomy of the short arm with parts of the long arm of chromosome 9 and a small part of the long arm of chromosome 4. A surgical repair of the heart defect was not performed by the known high risk of severe mental retardation of partial trisomy 9. The child died at the age of six months.

Morphologic characterization and assessment of mitral regurgitation after repair of atrioventricular defects in children

Severe postoperative mitral regurgitation renders information on the underlying mechanism before reoperation very important, as a potential for mitral valve reconstruction may facilitate the decision whether to reoperate, especially in the very young. This study compares the efficacy of transthoracic echo-cardiography (TTE) and left-ventricular angiography with that of transesophageal echocardiography (TEE) for detection of the mechanism underlying mitral regurgitation and its quantitative assessment in children after repair of common atrioventricular septal defect. Five children aged 1.5 to 16 years were evaluated by TTE, TEE, and angiography for postoperative mitral regurgitation 1 to 21 months after initial repair. TEE showed septal detachment of the mitral leaflet in four patients and reopening of the mitral cleft in one patient as the cause of mitral regurgitation whereas TTE failed in four and angiography in all patients. TEE allows definite identification of morphologic characteristics of mitral regurgitation and reliable assessment of its severity. Thus redo surgery may be safety performed on the bases of TEE findings alone without confirmation by cardiac catheterization.

Thromboembolism and resistance to activated protein C in children with underlying cardiac disease

OBJECTIVES

In the majority of cases, resistance to activated protein C is caused by the point mutation Arg506 to Gln in the factor V gene and has emerged as the most important hereditary cause of thromboembolism.

METHODS

To determine to what extent resistance to activated protein C was present in children with thromboembolism and underlying cardiac disease, its occurrence was retrospectively investigated. By using a method based on activated partial thromboplastin time, with DNA technique derived from the polymerase chain reaction, we investigated nine children with underlying cardiac disease in whom thromboembolism had previously occurred.

RESULTS

Heterozygous Arg506-to-Gln mutation in the factor V gene was diagnosed in five of the nine children investigated. In addition, protein C type I deficiency w as found in three patients, and two of the nine children showed increased lipoprotein (a) plasma values. Risk factors were present in all children with symptoms.

CONCLUSIONS

These data indicate that deficiencies in the protein C anticoagulant pathway are likely to play an important role in the early manifestation of thromboembolism in children with underlying cardiac disease.

Thrombolytische Therapieformen im Kindesalter

Thrombosen und Embolien sind im Kindesalter nicht zu unterschätzen. Typische Ursachen sind zentrale Katheter, Herzkatheteruntersuchungen mit Intervention, größere operative Eingriffe neben primären oder sekundären Mangelzuständen von Gerinnungsinhibitoren. Geschätzt wird eine Inzidenz von etwa 5 auf 10000 hospitalisierte Kinder mit einer Mortalität von 2%, einer Rezidivrate von 7-18% sowie der Entwicklung postthrombotischer Syndrome in 20% der Fälle. Die Erfahrungen mit thrombolytischen Therapieformen im Kindesalter sind begrenzt. In mehreren Studien gut dokumentiert sind Thrombolysen von akuten Verschlüssen der Femoralarterien nach Herzkatheruntersuchungen: In 10 Studien wurden 147 von 164 (90%) Patienten erfolgreich lysiert, lokale Blutungen traten bei 41 von 164 (25%) auf. Auf kleinere Studien begrenzt sind Therapien von Thrombosen in den Nierenvenen, den zentralvenösen Gefäßen sowie im rechten Atrium. Erfahrungen mit Lysen linksatrialer, linksventrikulärer oder aortaler Thrombosen sowie Lungenembolien im Kindesalter liegen bisher nur in Form von Kasuistiken vor.

Laborkontrollen vor, während und nach einer Thrombolysetherapie im Kindesalter

Thrombosen im Kindes- und Jugendalter sind ernst zu nehmende Ereignisse und erfordern neben einer Ursachenklärung eine adäquate Therapie. Bei den heute üblichen Lysetherapien im Kindesalter haben Laboranalysen neben der Überwachung der Antikoagulanzientherapie die wesentliche Aufgabe der Therapiesteuerung. Die Laboranalyse besteht vor Thrombolysetherapie in der Bestimmung von Thrombozytenzahl, Hämoglobin, TPZ, aPTT, Fibrinogen, Antithrombin, Plasminogen und D-Dimer. Während der Lysetherapie sollen zur Therapiesteuerung, zur Erfassung von möglichen Nebenwirkungen und Begleitantikoagulation Thrombozyten, Hämoglobin, aPTT, Antithrombin, Plasminogen und D-Dimer bestimmt werden. Zur Verhinderung einer Reokklusion unter voller Antikoagulation nach Thrombolyse besteht die Laborkontrolle in der Akutphase in der Analyse von aPTT, Antithrombin und D-Dimer.

Left atrial thrombus in a 10-month-old boy--successful thrombolysis with recombinant tissue-type plasminogen activator after open-heart surgery: review of the literature

A 10-month-old boy with major left atrial thrombus following cardiac surgery was treated with intravenously administered recombinant tissue-type plasminogen activator (rt-PA; Actilyse, Thomae-Behring, Germany). The left atrial thrombus was diagnosed by Doppler echocardiography 8 days after complete correction of a ventricular septal defect. rt-PA therapy was administered over a 10-day period. Significant hemopericardium occurred 50 h after the start of thrombolytic therapy. rt-PA infusion was discontinued for 20 h to insert a pericardial drainage. The initial rt-PA dose was 0.1 mg/kg over 10 min followed by a continuous daily infusion of 1.7 mg/kg together with low-dose heparin. Thrombolytic therapy was restarted 20 h after pericardial drainage was inserted. The daily rt-PA dose was gradually raised to 3 mg/kg (total dose: 18 mg/kg). On day 7 and 8 a clear decrease in P-plasminogen and P-antithrombin occurred, requiring additional fresh frozen plasma and P-antithrombin concentrate substitution. One day later, without further side effects, complete thrombolysis occurred. Although hemopericardium demanded discontinuation of thrombolytic therapy, rt-PA administration, closely monitored by Doppler echocardiography, was continued, leading to complete thrombolysis of the left atrial thrombus in the early postoperative period. We consider the literature dealing with rt-PA thrombolysis in infancy we discuss this case report.

Plasma thrombomodulin concentrations in infants and children undergoing cardiac catheterization

Circulating plasma thrombomodulin (TM) is an endothelial cell marker which may reflect endothelial injury. To find out to what extent diagnostic cardiac catheterization irritates vascular endothelium we conducted a prospective study in 91 children. Soluble TM concentrations, along with thrombin generation, were measured before, at the end of and 24 hours after cardiac catheterization. Compared to starting values, TM concentrations showed a clearly significant increase at the end of cardiac catheterization and returned to pretreatment values 24 hours later. Thrombin generation followed a similar pattern. Five out of the 91 children demonstrated resistance to activated protein C (APCR). With respect to the remaining 86 children, all five APCR cases showed increased thrombomodulin concentrations along with enhanced thrombin generation. Data from this study indicate that increased TM concentrations after cardiac catheterization in children are a sign of short-term endothelial damage. Furthermore, together with enhanced thrombin generation, elevated plasma concentration of soluble TM may reflect this receptor's possible anticoagulant properties.

Renal insufficiency in neonates after cardiac surgery

Renal failure after cardiac surgery using cardiopulmonary bypass (CPB) is well understood for infants, children and adults. The perioperative risk factors after CPB for immature kidneys in newborns are not well known. This retrospective study investigates perioperative risk factors for renal insufficiency in neonates. I) Preoperative: Age; weight, performed angiography, amount of dye used in angiography, renal disease and creatinine. II) Intraoperative: Duration of operation, duration of MAP < 40 mmHg, use of deep hypothermia, in-out fluid balance, duration of CPB, duration of circulatory arrest and cross-clamp time. III) Postoperative: Creatinine, use of catecholamines, use of nitroglycerine (NG) or phosphodiesterase inhibitors (PDI) and additional antibiotics. From Jan. 1990 to Dec. 1994 50 neonates underwent cardiac surgery using CPB (n = 23 transposition of the great arteries; n = 4 pulmonary atresia; n = 6 critical pulmonary stenosis; n = 5 hypoplastic left heart syndrome; n = 3 Ebstein's anomaly; n = 2 interrupted arch with hypoplastic left ventricle; n = 2 single ventricle; n = 1 each: double outlet right ventricle, tricuspid atresia, critical aortic stenosis, rhabdo-myosarkoma, corrected transposition of the great arteries.) Thirty-one patients entered the study. Depending on the postoperative creatinine level two groups (group I: creatinine <1 mg/dl and group II: >1 mg/dl) were created. The diureses between the two groups did not differ. Comparing the patients of group I vs. group II, patients of group I were younger (mean age: 7.7 d. vs. 11.4 d), lighter (mean weight: 3260 g vs. 3430 g), less had angiography (44% vs. 77%), received more dye (mean amount: 14 ml vs. 7 ml), the duration of MAP < 40 mmHg while on CPB was longer (mean duration 3 min vs. 21 min), more patients were operated on using deep hypothermia (55% vs. 27%), the postoperative in-out-fluid balance was more positive (mean balance +413 ml vs. +221 ml), received postop. more frequently high doses of catocholamines and less common NG or PDI, but more often additional antibiotics. The duration of circulatory arrest (mean time: 60 min vs. 55 min) and cross clamp time (mean time: 68 min vs. 65 min) seems not to be a risk factor and vasodilators given simultaneously with catecholamines may have preventive effects on postoperative renal insufficiency. Immature kidneys may play an outstanding role in the susceptibility of damaging factors. Further investigation with a larger number of patients allowing to obtain statistical significant risk factors are required.

Flush heparin during cardiac catheterisation prevents long-term coagulation activation in children without APC-resistance-preliminary results

This study was designed to prospectively evaluate haemostatic activation in 75 children undergoing cardiac catheterisation with intermittent flush heparin (10 IU/ml saline) and to relate these data to clinical findings and inherited risk factors for thrombophilia. In addition to flush heparin in infants < 6 months of age in whom additional arterial catheterisation was performed (n = 5) or patients with thrombophilia, heparin (300-400 IU/kg/d) was administered for a further 24 h. APTT was prolonged and anti Xa activity was significantly increased at the end of catheterisation and returned to normal 24 hours later. Whereas thrombin generation (F1 + 2) showed a significant coagulation activation at the end of catheterisation, no concomitant fibrinolytic activation (D-Dimer) was observed. Four children showed resistance to APC: one of them in whom stroke had occurred before and one additional child heterozygous for APCR received further prophylactic heparin. Two neonates with APCR and flush heparin only suffered from thrombosis after catheterisation. No further thrombotic events occurred. This study indicates that low-dose flush heparin during catheterisation may prevent long-term haemostatic activation in children without thrombophilia. Whether further heparin after cardiac catheterisation in children with APCR prevents vascular insults requires a more intensive study.

Resistance to activated protein C (APCR) in children with venous or arterial thromboembolism

Resistance to activated protein C (APCR), in the majority of cases due to the point mutation Arg 506 Gln of the factor V gene, has emerged as the most important hereditary cause of venous thromboembolism. Using an activated thromboplastin time (aPTT) based method in the presence of APC together with a DNA technique based on the polymerase chain reaction, we investigated 37 children with venous (V: n=19) or arterial (A: n=18) thromboembolism and 196 age-matched healthy controls for the presence of this mutation. In the control group 10 children were detected to be heterozygous for the factor V Leiden mutation, indicating a prevalence of 5.1%. 10/19 children (52%) with venous thrombosis and 7/18 (38%) patients with arterial thromboembolism showed the common factor V gene mutation. Additional inherited coagulation disorders were found in 1/10 (V:10%) and 2/7 (A:28%) APC-resistant patients. Inherited coagulation disorders without APCR were diagnosed in 3/9 (V: 33%) and 2/11 (A:18%) children. Furthermore, we diagnosed exogenous risk factors in 6/10 (V: 60%) and 2/7 (A: 28%) children with thrombosis and APCR. These data are evidence that APCR combined with exogenous reasons may play an important role in the early manifestation of thromboembolism during infancy and childhood.