Cardiac Muscle Training-A New Way of Recognizing and Supporting Recovery for LVAD Patients in the Pediatric Population.

Patients with refractory heart failure due to chronic progressive cardiac myopathy (CM) may require mechanical circulatory support as a bridge to transplantation. A few patients can be weaned from support devices if recovery can be achieved. The identification of these patients is of great importance as recovery may be missed if the heart is unloaded by the ventricular assist device (VAD). Testing the load-bearing capacity of the supported left ventricle (LV) by temporarily and gradually reducing mechanical support during cardiac exercise can help identify responders and potentially aid the recovery process. An exercise training protocol was used in 3 patients (8 months, 18 months and 8 years old) with histological CM findings and myocarditis. They were monitored regularly using clinical information and functional imaging with VAD support. Echocardiographic examination included both conventional real-time 3D echocardiography (RT3DE) and speckle tracking (ST). A daily temporary reduction in pump rate (phase A) was followed by a permanent reduction in rate (phase B). Finally, pump stops of up to 30 min were performed once a week (phase C). The final decision on explantation was based on at least three pump stops. Two patients were weaned and successfully removed from the VAD. One of them was diagnosed with acute viral myocarditis. The other had chronic myocarditis with dilated myopathy and mild interstitial fibrosis. The noninvasive assessment of cardiac output and strain under different loading conditions during VAD therapy is feasible and helps identify candidates for weaning despite severe histological findings. The presented protocol, which incorporates new echocardiographic techniques for determining volume and deformation, can be of great help in positively guiding the process of individual recovery, which may be essential for selecting and increasing the number of patients to be weaned from VAD.

Left ventricular mass estimation by real-time 3D echocardiography favourably competes with CMR in congenital left ventricular disease.

Assessment of left ventricular mass (LVM) is important in the evaluation of patients with congenital heart disease (CHD) and cardiac magnetic resonance imaging (CMR) is the gold standard. Recent software allows LVM calculation by real-time 3-dimensional echocardiography (RT3DE). We investigated the impact of different software analysis tools on LVM determination by CMR or RT3DE in a cohort of patients with heterogeneous left ventricular (LV) disease. 37 subjects (17 patients, mean age 18.7 y; 20 controls, mean age 13.2 y) underwent CMR and RT3DE. CMR LVM and RT3DE calculations were done using two different LV-analysis software packages for each modality: CMR i) customized software "CMR HDZ", CMR ii) "CMR ISP"; RT3DE i) "Toshiba", RT3DE ii) "Tomtec", 4D LV-Analysis Version 3.1 (built 3.1.0.258661). Intra- and interobserver variabilities were calculated. Only RT3DE-derived LVM showed significant software-dependent differences. RT3DE-derived LVM (both softwares) was significantly higher than CMR-derived LVM (both softwares). The two different methods and four evaluation software packages for LVM assessment were well correlated with each other. Intra- and interobserver variability of LVM as assessed by each single modality or software was low. Despite software dependency and overestimation of RT3DE-assessed LVM by 5 to 10%, RT3DE still competes with the gold standard, CMR, even in patients with various forms of LV disease. The use of optimized software, especially for RT3DE, should improve the accuracy of LVM assessment, overcoming LVM overestimation.

The "Dog Bone Technique" A Novel Easy and Safe Catheter Maneuver for Aortic Arch and Coarctation Stenting.

BACKGROUND: Various techniques are described to facilitate stable stent implantation in aortic arch stenosis or coarctation. We describe an alternative technique, which due to its unique appearance during stent implantation, we have named "Dog Bone Technique" (DBT). TECHNIQUE: The stent/balloon assembly is placed across the stenosis, the long sheath is retrieved to uncover the distal 20-50% of the stent. The balloon is inflated with the pressure inflator just to expand slightly the stent. Thereafter the sheath is pulled back and the proximal end is uncovered and partially inflated; therewith the assembly takes the typical "dog bone" shape before complete inflation and final positioning. Repositioning of the stent and control angiography is possible at each time of this procedure. RESULTS: Between 1/2010 and 12/2014 we implanted 91 stents in 87 patients (mean age 20.2 years). About 71 patients had native or re-coarctation and 16 patients had transverse aortic arch stenosis. In 38 patients (44%) a pharmacological exercise test with Orciprenaline was performed during implantation resulting in high-cardiac output. In none of the patients reduction of cardiac output by adenosine or a rapid pacing of the right ventricle was required for stable stent implantation. All stents were implanted in the targeted position using this single balloon technique. There were no acute or short-term complications detected. CONCLUSION: DBT is a safe and feasible technique for aortic stent implantation even at high-cardiac output. Other additional techniques for stent placement are not necessary to obtain a stable final position in the target region.