Ute Blanz

Bovine valved venous xenografts for RVOT reconstruction: results after 71 implantations

BACKGROUND Pediatric right ventricular outflow tract (RVOT) reconstruction with homo- or porcine xenografts is problematic because of limited availability, lack of material for reconstruction, early degeneration, and tissue ingrowth. Contegra, a bovine jugular vein graft, might be an interesting alternative to overcome these problems. PATIENTS AND METHODS Within a Federal Drug Administration controlled study, we implanted 71 Contegra pulmonary valved conduits from May 1999 to September 2001 in 71 patients (male/female 33/38) in the age range 2 days-17.4 years, median 1.2 years. Twenty five were primary repairs, 22 had previous graft implantations, and 24 had other repairs/palliations. Preoperative diagnoses: truncus arteriosus communis (19 patients), tetralogy of Fallot (32), double outlet right ventricle (13), transposition of the great arteries (5), and two rare complex malformations. The size of implanted Contegra conduits ranged from 12 to 22 mm. Echocardiography was performed at 1 and 3 months, and then every 3 months postoperatively. Follow-up time was 27 months (maximal), 80 years in total. Results were compared with our 52 homograft- and 30 Tissuemed porcine xenograft recipients. RESULTS Contegra enables the surgeon to perform all anastomoses without additional material. Its tissue is very apt for suturing and its insufficiencies are common, but without clinical significance or tendency to increase. We saw no sign of conduit or valve degeneration during the whole follow-up up to 27 months. There were no device related adverse events. Redos: five for peripheral pulmonary arteries, two residual ventricular septum defect (VSD) closures. There were six deaths (five early, one late). The maximal transvalvular gradients of 25-42 mmHg were measured in seven patients; these gradients did not increase further during the follow-up. Six patients with completely intact Contegra conduits developed pressure gradients of more than 70 mmHg immediately distal from the conduit. At 27 months, Contegra grafts were advantageous compared to homografts with respect to survival and freedom from explantation. Right ventricle to left ventricle (RV/LV) ratio development and freedom from explantation/redo were equal for Contegra conduits and homografts. Porcine Tissuemed xenografts were significantly inferior. CONCLUSION The Contegra conduit offers unique tailoring and suturing options for primary and redo RVOT reconstruction. At 27 months, its durability seems at least equivalent to homografts and is superior to porcine Tissuemed xenografts.

Results after Norwood procedure and subsequent cavopulmonary anastomoses for typical hypoplastic left heart syndrome and similar complex cardiovascular malformations.

OBJECTIVE From October 1989 to June 1998, 60 patients have undergone the Norwood procedure (stage I) at our institution. The results of the staged surgical reconstruction and risk factors were analysed. Typical hypoplastic left heart syndrome (HLHS) and complex lesions with aortic hypoplasia were compared with each other. PATIENTS Typical HLHS: N = 48, median age 15 days (5-190 days), median weight 3.6 kg (2.6-5.3 kg). Complex lesions (dominant left ventricle): N = 12, median age 59 days (10-884 days), median weight 3.4 kg (2.4-12 kg). RESULTS Typical HLHS: The stage-I hospital survival was 73% (35/48). It improved from 60% (95% confidence interval: 49-71%) during 1989-1994 to 91% (95% CI: 81-100%) during 1997-1998. Seven patients were lost late. The right ventricular end diastolic diameter (P = 0.015), shortening fraction (P = 0.027), and the presence of an obstructed pulmonary venous return (P = 0.0032) were significant risk factors. 23 children underwent stage-II operation with four (17%) deaths. All survivors experienced an improvement of their statomotoric development. Stage-III operation was performed in 13 patients with no hospital death. Follow up after stage-III procedure was 7 months to 7 years. 4 year actuarial survival, including hospital mortality and deaths at subsequent stages, improved from 28% (95% CI: 18-38%) during 1989-1994 to 58% (95% CI: 48-68%) during 1994-1997. No patient had signs of myocardial insufficiency. Complex lesions: Stage-I hospital survival was 83% (10/12) with no late death. Stage-II was performed in 8 and stage-III in 6 patients with no death respectively. CONCLUSION In typical HLHS the results have improved over time. Both size and function of the right ventricle determined significantly stage-I survival. An early operation prevents the natural progression of pulmonary blood flow and may weaken all three risk factors. Patients with complex lesions seemed to have better chances of surviving the early postoperative period. The multistage reconstructions have become a realistic option for patients with HLHS and similar lesions, regardless of the morphologic subtype or diminutiveness of the aorta, and lead to an acceptable quality of life.

Acute fulminant myocarditis in children and adolescents: the role of mechanical circulatory assist.

We report children and adolescents in fulminant myocarditis undergoing prolonged circulatory support with different assist devices. Between 1994 and 2004, seven children and adolescents (aged 7–18 years, mean age 13.5 years) were treated with VADs (5 Thoratec, 1 Medos, 1 Novacor) for circulatory support. Three patients underwent left ventricular support; biventricular support was necessary in four patients. Four patients (three left VADs, one bi-VAD) could be successfully bridged to heart transplantation after a mean support time of 163 days (56–258 days). One 7-year-old girl (Medos-BVAD) died after a support time of 11 days because of irreversible multiorgan failure. One 18-year-old patient was successfully weaned from Thoratec BVAD after 66 days with complete recovery of left ventricular function. As good markers, atrial and brain natriuretic peptides were found which reached normal values after recovery of myocardial function. A 15-year-old girl is still on the device. In children or adolescents with irreversible shock in fulminant myocarditis with an anticipated mortality of 100%, both successful bridging to heart transplantation and successful bridging to recovery are possible. Young patients with fulminant myocarditis should be rapidly transferred to a clinic with a mechanical circulatory support program to offer this life-saving option.

Endocardial pacing after Fontan-type procedures.

Background: Sinus node dysfunction is a frequent complication of Fontan‐type procedure. Epicardial pacing is considered as the standard treatment for these patients.

Mechanical valve replacement in congenital heart defects in the era of international normalized ratio self-management

As the number of patients with congenital heart defects requiring heart valve replacement increases, the need for durable valve substitutes with good hemodynamic performance and a low incidence of complications becomes more apparent. The use of porcine xenografts is burdened with early fibrocalcific degeneration, whereas the use of mechanical heart valves led to an increased number of thromboembolic events, especially when implanted in the right side of the heart. We report on our experiences implanting bileaflet heart valves in congenital heart defects since the introduction of international normalized ratio (INR) self-management. The data of 68 long-term survivors (33 males, 35 females) who underwent mechanical heart valve replacement in congenital heart defect were reviewed. Patient age at the time of valve replacement ranged from 5 months to 61 years (mean 21 years). Underlying diagnoses were tetralogy of Fallot (n = 33), morbus Ebstein (n = 4), atrioventricular canal (n = 13), truncus arteriosus communis (n = 5), transposition of the great arteries (n = 10), and congenitally corrected transposition of the great arteries (n = 3). In all patients, bileaflet valves were implanted (St. Jude Medical n = 40, Carbomedics n = 28). Anticoagulation was performed using dicumarol (Marcumar) and INR self-management in all cases. The mean follow-up was 72 months (range 6–132 months; 409 patient-years). Valve thrombosis developed in 3 of 68 patients (4.4%, all three had tetralogy of Fallot, mean age 9.8 years) after a mean follow-up of 3.5 years. In two of these three patients, re-pulmonary valve replacement was necessary, whereas the third patient was treated by thrombolysis. From our experience, we conclude that mechanical heart valve replacement is a good therapy option with a low complication rate for patients with congenital heart defects requiring valve replacement, especially when INR self-management is performed.

Scimitar syndrome presenting in adults.

Abstract  Scimitar syndrome is a rare and complex congenital anomaly, which is characterized by the image of a Turkish sword on the chest X‐ray. Very few cases in adults are reported in the literature. The long‐term results of scimitar syndrome after surgical correction remain disappointing. We report an adult patient with scimitar syndrome undergoing surgery at our center.

ECMO for cardiac rescue in a neonate with accidental amiodarone overdose

Intravenous (IV) amiodarone hydrochloride has proven to be a very effective antiarrhythmic treatment option for a variety of ventricular and supraventricular arrhythmias in adults and paediatric patients. Amiodarone is known to have significant side effects and these especially include profound hypotension in animals and adults, vasodilatation, negative inotropic effects, and significant bradycardia especially when administered intravenously. Special caution is warranted in patients with decreased contractility and end-stage heart failure. We present a case of accidental amiodarone overdose in a newborn treated for atrial flutter resulting in cardiovascular collapse. The patient could be rescued by rapid initiation of VA-ECMO treatment. The patient survived without neurological damage.

Long‐Term Mechanical Circulatory Support in Pediatric Patients

This retrospective study reviews our results regarding the long-term support in pediatric patients using two ventricular assist systems between January 2008 and April 2014. We implanted the Berlin Heart EXCOR in 29 patients (median age 3.4 years [interquartile range (IQR) 0.2-16.5], median weight 13 kg [IQR 4.2-67.2]). Twenty-two patients (75.8%) received a left ventricular assist device. Three patients (10.3%) had single-ventricle physiology. One patient (3.4%) had mechanical mitral valve prosthesis. The HeartWare System was implanted in nine patients. The median age was 15.6 years (IQR 12.2-17.9), and the median weight was 54.9 kg (IQR 27.7-66). In the Berlin Heart group, the median support time was 65 days (IQR 4-619), with 3647 days of cardiac support. Nineteen patients (65.5%) were transplanted, six patients (20.7%) recovered, one patient (3.4%) is on support, and three patients (10.3%) died on support. Survival rate was 89.7%. Fourteen blood pumps had been exchanged. Four patients (13.8%) had local signs of infection, and three patients (10.3%) had neurological complications. In the HeartWare group, the median support time was 180 days (IQR 1-1124), with 2839 days of cardiac support. Four patients (44.4%) had local signs of infection, and three (33.3%) had neurological complications. Eight patients (88.9%) have been transplanted, and one patient (11.1%) died on support. Survival rate was 88.9%. Excellent survival is possible after long-term mechanical circulatory support in patients with two- and single-ventricle physiology with a low rate of adverse events.

Mechanical valve replacement of the systemic atrioventricular valve in children.

In children with systemic atrioventricular valve disease (SAVVD), reconstructive surgery is the primary goal. However, in cases with severely dysplastic valves or failed repair, valve replacement is the only option. The purpose of this study was to assess the early and late outcome following mechanical valve replacement in SAVVD. Between 1989 and 2003, 31 children underwent mechanical valve replacement (19 St. Jude Medical, 12 Carbomedics) in SAVVD (27 mitral, 3 tricuspid in corrected transposition of the great arteries, 1 common in an univentricular heart) at our institution. The ages ranged from 3 months to 15 years (mean 4 years) and body weight varied between 4.2 and 57 kg (mean 13.3 kg). The size of prostheses ranged between 16 and 31 mm (mean 23.9 mm). The main indication for valve replacement was severe insufficiency of left atrioventricular valve (84%); 84% of the patients had had a previous cardiac operation. The overall hospital mortality was 6.5% The mean follow up was 7.7 years (range 2–13 years). Ninety percent of children represent sinus rhythm, 87% are in NYHA class I. All patients were placed on a regimen of Phenprocoumon aiming to maintain the international normalized ratio (INR) between 3.0 and 4.0. Since 1994, INR self-management of oral anticoagulation was performed either by the patient or his or her parents. There was no anticoagulation-related complication in this patient group. Mechanical valve replacement in left atrioventricular valve disease carries a low operative risk across the spectrum of pediatric age despite previous operations in most cases. Long-term survival and quality of life are good in nearly all cases. The rate of anticoagulation-related complications is very low, especially when INR self management is performed.

Results of staged reconstruction for hypoplasia of the left heart: an experience of 12 years from one institution

BACKGROUND We reviewed our 12-year experience with staged reconstruction for hypoplasia of the left heart, examining the results of each surgical step and the impact of the year of the Norwood operation on survival. We compared survival of patients with hypoplasia of the left heart subsequent to completion of the Fontan circulation to survival of patients with a dominant left ventricle undergoing a Fontan procedure. PATIENTS Between 1989 and 2001, we performed a first stage procedure in 89 patients. Their median age was 9 days, with a range from 2 to 140 days, and the median weight was 3.4 kg, with a range from 2.4 to 5.4 kg. RESULTS Survival at 1, 4, and 10 years was 55%, 49%, and 49%, respectively. We experienced 23 early deaths (26%), and 12 deaths between the stages of the Norwood cascade. Of our patients, 42 underwent the second stage, and 30 the third stage. Prior to the first stage, symptoms of necrotising enterocolitis, and of obstructed pulmonary venous return, influenced survival significantly. The latter was eliminated as risk factor when surgery was performed within the first week of life. During the later part of our experience, survival at the first stage operation improved significantly, with survival at 3 years increasing from 42% to 75% for the patients at standard-risk (p = 0.017), and from 17% to 42% for those deemed to be at high-risk (p = 0.1). No deaths occurred in 23 patients older than 3 years of age, all of whom had proceeded through the third stage. After completion of the Fontan circulation, the survival of the patients with hypoplasia of the left heart at 4 years was comparable to the survival of patients undergoing the Fontan procedure with a dominant left ventricle (88% versus 90%, p = 0.8). CONCLUSIONS Early and intermediate survival has improved significantly over the period of 12 years. Late death has been uncommon, and none of our patients are listed for cardiac transplantation.