Hakan Akintuerk

Stenting of the Arterial Duct and Banding of the Pulmonary Arteries

Background—Outcome of patients with hypoplastic left heart (HLH) is mainly influenced by the successful first-step palliation according to the Norwood procedure. An alternative approach is heart transplantation (HTX). The feasibility of ductal stenting in newborns with duct-dependent systemic blood flow and bilateral pulmonary artery banding has been reported. But it remains to be elucidated whether this approach allows a new strategy for patients with HLH. Methods and Results—In patients with various forms of HLH (n=11) and prostaglandin E-1 administration, ductal stenting was performed with balloon expandable Jo stents or Saxx stents. Bilateral pulmonary artery banding was surgically accomplished 1 to 3 days after the transcatheter procedure. Unrestricted blood flow through the interatrial septum was secured by balloon dilatation atrial septotomy, as required. Interventional procedures were performed with no mortality. Stent and ductal patency were achieved for up to 331 days. Two patients underwent HTX, and 8 patients had a palliative 1-stage procedure with reconstruction of the aortic arch and bidirectional cavopulmonary connection at the age of 3.5 to 6 months. There were 2 deaths. One patient with preoperative right heart failure died after the reconstructive surgery, and 1 patient died 4 months after ductal stenting and bilateral banding awaiting HTX. Conclusions—The present study is the first clinical trial showing that stenting the duct followed by bilateral pulmonary artery banding in newborns with HLH allows the combination of neoaortic reconstruction, which is part of first-stage palliation of HLH, with the establishment of a bidirectional cavopulmonary connection. Additionally, it allows the chance for HTX after extended waiting periods.

Stenting of the ductus arteriosus and banding of the pulmonary arteries: basis for various surgical strategies in newborns with multiple left heart obstructive lesions

Objective: To present an institutional experience with stent placement in the arterial duct combined with bilateral banding of the pulmonary artery branches as a basis for various surgical strategies in newborns with hypoplastic left heart obstructive lesions. Design: Observational study. Setting: Paediatric heart centre in a university hospital. Patients: 20 newborns with various forms of left heart obstructive lesions and duct dependent systemic blood flow. Interventions: Patients underwent percutaneous ductal stenting and surgical bilateral pulmonary artery banding. Atrial septotomy by balloon dilatation was performed as required, in one premature baby by the transhepatic approach. Main outcome measures: Survival; numbers of and reasons for palliative and corrective cardiac surgery. Results: One patient died immediately after percutaneous ductal stenting. One patient died in connection with the surgical approach of bilateral pulmonary banding. Stent and ductal patency were achieved for up to 331 days. Two patients underwent heart transplantation and two patients died on the waiting list. Ten patients had a palliative one stage procedure with reconstruction of the aortic arch and bidirectional cavopulmonary connection at the age of 3.5–6 months. There was one death. One patient is still awaiting this approach. Two patients received biventricular repair. In one, biventricular repair will soon be provided. Conclusions: Stenting the arterial duct combined with bilateral pulmonary artery banding in newborns with hypoplastic left heart or multiple left heart obstructive lesions allows a broad variation of surgical strategies depending on morphological findings, postnatal clinical conditions, and potential ventricular growth.

Stent implantation in the ductus arteriosus for pulmonary blood supply in congenital heart disease

Indications for catheter‐based interventions in patent ductus arteriosus (PDA)‐dependent pulmonary blood flow have yet to be defined. The aim of this study was to assess the acute and midterm outcome after stent implantation in the PDA. Between 1996 and 2002, ductal stenting was performed in 21 neonates and infants (14 females/7 males) to maintain pulmonary blood supply in cyanotic congenital heart disease (CHD). Balloon‐expandable stents were implanted in the PDA with a final diameter of 4–5 mm without procedural deaths. Stent patency was achieved for 8–1,130 days (median, 142). Reintervention was necessary in nine patients. Overall survival rate after 6 years was 86%. Two neonates died a few days after the procedure due to right heart failure not related to PDA stenting. Corrective surgery was possible in six patients. An additional aortopulmonary shunt was needed in three patients; Fontan type operations were performed in six. One patient died after bidirectional Glenn shunt, another five reached palliation by additional perforation of the atretic valve/balloon valvuloplasty, and two are awaiting surgery. We conclude that in many patients with cyanotic CHD, especially in those with ductal pulmonary perfusion and additional forward flow from the right ventricle, ductal stenting is an effective transcatheter approach. Morphology of the PDA predicts the risk of restenosis and necessity of reintervention. Growth of the pulmonary vascular bed allows corrective or palliative surgery, and some patients can be cured by the intervention alone. Catheter Cardiovasc Interv 2004;61:242–252.

rFVIIa in the treatment of persistent hemorrhage in pediatric patients on ECMO following surgery for congenital heart disease.

Background:  Patients who require extracorporeal membrane oxygenation (ECMO) postsurgery for congenital heart disease (CHD) frequently experience severe bleeding episodes. Whereas recombinant‐activated factor VII (rFVIIa) has proven efficacy in counteracting intractable hemorrhage in various scenarios, its use in patients on ECMO is limited by the increased risk for thrombotic events.

A regenerative strategy for heart failure in hypoplastic left heart syndrome: intracoronary administration of autologous bone marrow-derived progenitor cells.

Novel surgical strategies have dramatically improved the initial outcome of newborns with hypoplastic left heart syndrome. However, the single systemic right ventricle remains a major challenge, with limited effectiveness of pharmacologic therapy. The present case documents that the intracoronary administration of autologous bone marrow-derived progenitor cells is technically feasible in a critically ill infant with hypoplastic left heart syndrome and severe heart failure after a hybrid comprehensive stage II procedure. Cell therapy might represent an option before heart transplantation in children with single ventricle physiology presenting with severe heart failure.

Implantable Cardioverter Defibrillator in a Child Using a Single Subcutaneous Array Lead and an Abdominal Active Can

This report describes the case of an 8‐year‐old boy with hypertrophic cardiomyopathy (HCM) who underwent ICD implantation for recurrent syncope. To avoid vascular complications and to minimize the surgical approach in this small child, a nonthoracotomy ICD system was chosen using a single subcutaneous array lead with only one finger, an abdominally placed active can, and epicardial dual chamber pacing and sensing electrodes. During an 8‐month follow‐up, DFT was confirmed and there were no ventricular tachycardia or complications. It appears to be a safe device for the prevention of sudden cardiac death in infants and small children. (PACE 2004; 27:117–119)

Sox2 Transduction enhances cardiovascular repair capacity of blood-derived mesoangioblasts

Rationale: Complementation of pluripotency genes may improve adult stem cell functions. Objectives: Here we show that clonally expandable, telomerase expressing progenitor cells can be isolated from peripheral blood of children. The surface marker profile of the clonally expanded cells is distinct from hematopoietic or mesenchymal stromal cells, and resembles that of embryonic multipotent mesoangioblasts. Cell numbers and proliferative capacity correlated with donor age. Isolated circulating mesoangioblasts (cMABs) express the pluripotency markers Klf4, c-Myc, as well as low levels of Oct3/4, but lack Sox2. Therefore, we tested whether overexpression of Sox2 enhances pluripotency and facilitates differentiation of cMABs in cardiovascular lineages. Methods and Results: Lentiviral transduction of Sox2 (Sox-MABs) enhanced the capacity of cMABs to differentiate into endothelial cells and cardiomyocytes in vitro. Furthermore, the number of smooth muscle actin positive cells was higher in Sox-MABs. In addition, pluripotency of Sox-MABs was shown by demonstrating the generation of endodermal and ectodermal progenies. To test whether Sox-MABs may exhibit improved therapeutic potential, we injected Sox-MABs into nude mice after acute myocardial infarction. Four weeks after cell therapy with Sox-MABs, cardiac function was significantly improved compared to mice treated with control cMABs. Furthermore, cell therapy with Sox-MABs resulted in increased number of differentiated cardiomyocytes, endothelial cells, and smooth muscle cells in vivo. Conclusions: The complementation of Sox2 in Oct3/4-, Klf4-, and c-Myc-expressing cMABs enhanced the differentiation into all 3 cardiovascular lineages and improved the functional recovery after acute myocardial infarction.

Hybrid therapy for hypoplastic left heart syndrome: Myth, alternative, or standard?

OBJECTIVE This retrospective study presents our operative results, mortality, and morbidity with regard to pulmonary artery growth and reinterventions on the pulmonary artery and aortic arch, including key features of our institutional standards for the 3-stage hybrid palliation of patients with hypoplastic left heart syndrome. METHODS Between June 1998 and February 2015, 182 patients with hypoplastic left heart structures underwent the Giessen hybrid stage I procedure. Among these, 126 patients with hypoplastic left heart syndrome who received a univentricular palliation or heart transplantation were included in the main analysis. Median age and body weight of patients at hybrid stage I were 6 days (0-237) and 3.2 kg (1.2-7), respectively. Comprehensive stage II operation was performed at 4.5 months (2.9-39.5), and Fontan completion was established at 33.7 months (21.1-108.2). Operative and interstage mortality, morbidity, growth and reinterventions on the pulmonary arteries, and long-term operative results of the aortic arch reconstruction were assessed. RESULTS Median follow-up time after Giessen hybrid stage I palliation was 4.6 years (0-16.8). Operative mortality at hybrid stage I, comprehensive stage II, and Fontan completion was 2.5%, 4.9%, and 0%, respectively. Cumulative interstage mortality was 14.2%. At 10 years, the probability of survival is 77.8%. Body weight (<2.5 kg) and aortic atresia had no significant impact on survival. McGoon ratio did not differ at comprehensive stage II and Fontan completion (P = .991). Freedom from pulmonary artery intervention was estimated to be 32.2% at 10 years. Aortic arch reinterventions were needed in 16.7% of patients; 2 reoperations on the aortic arch were necessary. CONCLUSIONS In view of the early results and long-term outcome, the hybrid approach has become an alternative to the conventional strategy to treat neonates with hypoplastic left heart syndrome and variants. Further refinements are warranted to decrease patient morbidity.

Potts Shunt and Atrial Septostomy in Pulmonary Hypertension Caused by Left Ventricular Disease

We report a 20-year-old patient with Shones complex and severe diastolic dysfunction of his small left ventricle (LV) in whom severe pulmonary hypertension and biventricular failure developed while he was awaiting combined heart-lung transplantation. We performed a percutaneous balloon atrial septostomy and a modified Potts shunt (13-mm graft from left pulmonary artery to descending aorta), with the aim of decompressing the hypertensive right ventricle (RV) by reducing left ventricular preload and left atrial hypertension. The procedures were uneventful. The patients condition improved rapidly and biventricular function was restored. In contrast to a Potts shunt in other conditions, patients with pulmonary hypertension caused by left ventricular disease may benefit from an additional atrial left-to-right shunt.

Renal function in children with heart transplantation after switching to CNI-free immunosuppression with everolimus

Behnke‐Hall K, Bauer J, Thul J, Akintuerk H, Reitz K, Bauer A, Schranz D. Renal function in children with heart transplantation after switching to CNI‐free immunosuppression with everolimus. 
Pediatr Transplantation 2011: 15: 784–789.