Eugen Sandica

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.

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.

ECMO for Cardiac Rescue after Accidental Intravenous Mepivacaine Application

Mepivacaine is a potent local anaesthetic and used for infiltration and regional anaesthesia in adults and pediatric patients. Intoxications with mepivacaine affect mainly the CNS and the cardiovascular system. We present a case of accidental intravenous mepivacaine application and intoxication of an infant resulting in seizure, broad complex bradyarrhythmia, arterial hypotension and finally cardiac arrest. The patient could be rescued by prolonged resuscitations and a rapid initiation of ECMO and survived without neurological damage. The management strategies of this rare complication including promising other treatment options with lipid emulsions are discussed.

Single center experience: Implantation failures, early, and late complications after implantation of a partially biodegradable ASD/PFO-device (BioStar®)

In the search for a biodegradable device that leaves nothing but the tissue of the patient after complete endotheliazation and absorption, the BioSTAR® device was introduced in 2007 (CE Mark in European community and HPB in Canada) for ASD and PFO closure. It consists of a metal framework covered by a biodegradable membrane generated from a layer of porcine collagen that is broken down and absorbed over time. In a sheep model, the results were promising, showing complete closure of the defect with degradation of approximately 90% of the implanted membrane material after two years.

Stenting of the right ventricular outflow tract in symptomatic neonatal tetralogy of Fallot.

There is ongoing debate regarding the initial management of symptomatic neonates with tetralogy of Fallot. Although neonatal repair can be performed with low mortality, it is associated with increased morbidity and long-term impact on right ventricular performance. Traditionally, the modified Blalock-Taussig shunt remains the palliative procedure of choice. Differential pulmonary artery flow may occur and subsequently result in underdevelopment and distortion of pulmonary vessels. Transcatheter therapy was previously limited to balloon valvulotomy when the obstruction is predominantly at the pulmonary valve level. Stenting of the right ventricular outflow tract can enable adequate forward flow; however, pulmonary regurgitation may impact on right ventricular performance and cardiac output. Stenting of the right ventricular outflow tract with valve sparing placement of the stent thus treating the underlying pathophysiology of the hypercyanotic spells provides a safe and effective management strategy, improving arterial oxygen saturation, avoiding pulmonary regurgitation and encouraging pulmonary artery growth.

Left ventricular rotation and right-left ventricular interaction in congenital heart disease: the acute effects of interventional closure of patent arterial ducts and atrial septal defects.

BACKGROUND Left ventricular rotation is physiologically affected by acute changes in preload. We investigated the acute effect of preload changes in chronically underloaded and overloaded left ventricles in children with shunt lesions. METHODS A total of 15 patients with atrial septal defects (Group A: 7.4 ± 4.7 years, 11 females) and 14 patients with patent arterial ducts (Group B: 2.7 ± 3.1 years, 10 females) were investigated using 2D speckle-tracking echocardiography before and after interventional catheterisation. The rotational parameters of the patient group were compared with those of 29 matched healthy children (Group C). RESULTS Maximal torsion (A: 2.45 ± 0.9°/cm versus C: 1.8 ± 0.8°/cm, p < 0.05), apical peak systolic rotation (A: 12.6 ± 5.7° versus C: 8.7 ± 3.5°, p < 0.05), and the peak diastolic torsion rate (A: -147 ± 48°/second versus C: -110 ± 31°/second, p < 0.05) were elevated in Group A and dropped immediately to normal values after intervention (maximal torsion 1.5 ± 1.1°/cm, p < 0.05, apical peak systolic rotation 7.2 ± 4.1°, p < 0.05, and peak diastolic torsion rate -106 ± 35°/second, p < 0.05). Patients in Group B had decreased maximal torsion (B: 1.8 ± 1.1°/cm versus C: 3.8 ± 1.4°/cm, p < 0.05) and apical peak systolic rotation (B: 8.3 ± 6.1° versus C: 13.9 ± 4.3°, p < 0.05). Defect closure was followed by an increase in maximal torsion (B: 2.7 ± 1.4°/cm, p < 0.05) and the peak diastolic torsion rate (B: -133 ± 66°/second versus -176 ± 84°/second, p < 0.05). CONCLUSIONS Patients with chronically underloaded left ventricles compensate with an enhanced apical peak systolic rotation, maximal torsion, and quicker diastolic untwisting to facilitate diastolic filling. In patients with left ventricular dilatation by volume overload, the peak systolic apical rotation and the maximal torsion are decreased. After normalisation of the preload, they immediately return to normal and diastolic untwisting rebounds. These mechanisms are important for understanding the remodelling processes.

Compression, distortion and dislodgement of large caliber stents in congenital heart defects caused by cardiopulmonary resuscitation: a case series and review of the literature

Abstract Stenting of vascular, extracardiac or lately intracardiac stenosis has become an established interventional treatment for a variety of problems in congenital or acquired heart disease. Most stent procedures are completed successfully and the long-term outcome is favorable in the majority of cases. Stent collapse or deformation is a well recognized entity in peripheral stents and can be attributed to insufficient radial force; it can also be attributed to excessive external forces, like deformation of stents in the right ventricular outflow tract, where external compression is combined with continuous movement caused by the beating heart. The protection of the thoracic cage may prove to be insufficient in extraordinary circumstances, such as chest compression in trauma or cardiopulmonary resuscitation (CPR). In this case series, we describe three patients in whom large endovascular stents were placed to treat significant stenosis of the aorta, the aortic arch or the venous system of the inferior vena cava close to the atrium. In all patients, CPR was necessary during their clinical course for various reasons; after adequate CPR, including appropriate chest compression all patients survived the initial resuscitation phase. Clinical, echocardiographic as well as radiologic re-evaluation after resuscitation revealed significant stent distortion, compression, displacement or additional vascular injury. The possibility of mechanical deformation of large endovascular stents needs to be considered and recognized when performing CPR; if CPR is successful, immediate re-evaluation of the implanted stents—if possible by biplane fluoroscopy—seems mandatory.

Adult congenital heart disease – Double-chambered right ventricle

Ute Blanz, MD · Eugen Sandica, MD Clinic for Thoracic and Cardiovascular Surgery Heart and Diabetes Center Northrhine-Westfalia Ruhr-University of Bochum, Germany Sirs: A 45-year-old male was examined for a history of progressing dyspnea over the last 10 years. In childhood he was diagnosed by clinical examination with a small ventricular septal defect which closed spontaneously and therefore no follow-up examinations had been performed. The transthoracic echocardiogram demonstrated a dilated right atrium, normal sized and competent av-valves, a normal left ventricle, marked right ventricular hypertrophy and a midcavitary stenosis with an estimated proximal right ventricular pressure of 145 mmHg. A gradient across the pulmonary valve could not be ruled out because of the turbulent flow at the infundibulum. Cardiac catheterization ruled out pulmonary hypertension and coronary artery disease. He was referred to our institution for surgical treatment. On physical examination there were no signs of chronic heart failure and a 3/6 harsh systolic ejection murmur was present at the left upper sternal border (183 cm, 110 kg, and RR 150/ 100 mmHg). Hemoglobin was 14.5 g/dl; the transcutaneous oxygen saturation was 99%. Electrocardiography showed right-ventricular hypertrophy and right-precordial ST-wave changes. Magnetic resonance imaging (MRI) was performed on a 1.5 Tesla Philips scanner using balanced turbo field echo (b-TFE) cine sequences in short breath-holds. The right atrium was enlarged and the foramen ovale was patent. A severe midcavitary stenosis was prominent in the hypertrophied right ventricle with a residual systolic lumen of 8 mm (Fig. 1 a–d arrowheads). The pulmonary valve showed no pathology; a small ventricular septal defect into the high pressure right chamber was suspected. MRI stroke volume measurements in the ascending aorta (92 ml), the main pulmonary artery (90 ml) and volumetric ventricular stroke volume measurements showed no shunting. The intraoperative transesophageal echocardiogram ruled out a residual ventricular defect and confirmed the severe midcavitary right ventricle stenosis (Fig. 1 d). Using a transtricuspid approach the altered muscle bundles in the right ventricle were exposed (Fig. 1 e) and completely resected (Fig. 1 f). The patent foramen ovale was closed directly. The patient had an uncomplicated postoperative course and was discharged 6 days later.

Intraoperative hybrid stenting of recurrent coarctation and arch hypoplasia with large stents in patients with univentricular hearts

BACKGROUND Obstruction of the reconstructed aortic arch, tubular hypoplasia and recurrent coarctation (RC) is an important risk factor in univentricular physiology. For the past two years we have adopted the concept of intraoperative hybrid stenting of RC and arch hypoplasia with large stents in patients with univentricular hearts as standard care procedure. METHOD/RESULT Retrospective analysis of the anatomy and procedural outcome of 14 patients was scheduled for intraoperative stenting of the aortic arch (12 during surgery for BCPS, 2 during Fontan completion). The median age was 5.3 months, weight 5.5 kg, height 62 cm. Five patients had tubular hypoplasia and 9 patients had distal stenosis of the aortic arch. Nine patients had a previous balloon dilatation. The mean diameter of the distal arch was 11.0mm, at the coarctation 5.1mm, at the level of the diaphragm 8.2mm (CoA-index 0.62). Intraoperative stenting was performed in 13/14 patients. Stents were implanted with a mean balloon diameter of 10.8mm (SD 3.4mm). The achieved final mean diameter was 9.8mm (mean, SD 2.8mm) with an oversized Coa-index of 1.2. There was no re-coarctation at a mean follow-up of 7.3 months (range 3 to 24), the maximum flow velocity of 2m/s across the stented lesion assessed by ECHO. CONCLUSION This hybrid approach is an easy and safe concept to manage recurrent aortic arch hypoplasia and stenosis. The use of large stents allows redilatation to adult size diameters later on.

Safety of Long-Term Mechanical Support With Berlin Heart EXCOR in Pediatric Patients.

Background. The Berlin Heart EXCOR Pediatrics is utilized at our center as a bridge to transplantation or bridge to recovery. This retrospective study reviews our results regarding the safety of long-term support and outcome. Methods. Between January 2008 and December 2010, 12 patients (6 females and 6 males) underwent implantation of a ventricular assist device. The median weight was 14.2 kg (range 4.2-51.6 kg) and the median age was 4.12 years (range 0.25-11.83 years). All patients were on inotropes, five patients required mechanical ventilation and three patients experienced cardiopulmonary resuscitation. Results. Eight patients received a left ventricular assist device and four patients received a biventricular assist device. Of the 12 patients, 8 were bridge to heart transplantation, in 2 patients explantation was possible, and 1 patient died on support. The median support time for these 11 patients was 151 days (range 4-488 days), with 2124 days of cardiac support. One patient is on support. Survival rate was 91.6%. Seven patients had a blood pump change once. Four patients had local signs of infection. There was no mediastinitis and thromboembolism. One patient had intracerebral hemorrhage. There was no death after heart transplantation or after explantation of the device. Conclusions. The Berlin Heart EXCOR is effective in bridging children of almost all ages and sizes to cardiac transplantation or myocardial recovery. Our experience proved that long-term support is possible with a low rate of adverse events.