Proof of Concept: A New Solution for Low-Profile Transcatheter Implantation of Optimus-L Stents in Small Children.

BACKGROUND: There is no stent designed or approved for use in infants. We sought to obtain in vitro and in vivo data on a new concept conceived to implant Optimus-L stents at infant vessel diameters and offer a potential long term stent solution. METHODS: Nineteen Optimus-L stents were mounted on 8 types of angioplasty balloons with diameters 6, 8, and 10 mm with the use of an injection-moulded hand crimper. We evaluated balloon-stent unit (BSU) stability before insertion and advancement through short Terumo introducers with incremental French size and possibility of side-arm contrast injections. Three types of long sheaths were tested. Stents were inflated to balloon nominal diameters and re-expanded to 18 and 23 mm. Stent recoil, foreshortening, and fracture were evaluated. In vivo implantations were performed afterward. RESULTS: In vitro: Medtronic Evercross balloons and modified Terumo Destination sheaths were the best combination: BSUs were inserted in 6 F sheaths with possible injections (for 6 and 8 mm balloons), and 7 F sheaths without injections (for the 10 mm balloon). Retrieving BSUs inside the sheath required 1 additional F-size. Boston Scientific Sterling and Balton Lovix balloons, as well as APT Braidin L guiding sheaths showed unsatisfactory performance. Dilation up to 23 mm was possible, and stent shortening was < 24% at 18 mm and < 37% at 23 mm. Recoil was limited, and no stent fractured. In vivo: Optimus-L stents were used to treat 2 infants with aortic coarctation and 2 children with pulmonary artery stenosis with the use of 8 mm balloons and low-profile access. CONCLUSIONS: Optimus-L stents can be implanted safely in small patients with a low-profile approach. These stents have the potential to achieve adult size while maintaining structural integrity.

Umbilical catheter placement aided by coronary guidewires.

Catheterization of the umbilical vessels has proven to be an effective and relatively rapid method for gaining central vascular access in neonates. However, it can be technically difficult, the procedure may last 30 min or longer, and it can be associated with complications in some patients. We suggest using a coronary guidewire during catheterization of umbilical vessels to support the placement of umbilical catheters and significantly reduce a risk for complications. We tested the proposed technique in 6 successful ex vivo bench tests of catheterization of the umbilical vessels in stillborn piglets immediately after birth. We are confident that using coronary guidewire as a guiding tool during catheterization of the umbilical vessels is a rapid and safe method. We expect that it allows to obtain a vascular access with lower risk for dangerous procedural complications, which could be a lifesaving in critically ill patients. However, the approach needs to be validated in a comparative study in neonates.

Management of a doubly folded, partially inflated Melody valve after outer balloon rupture: a case report.

This is a report of a rare complication during implantation of a Melody valve in an adult patient in whom the valve failed to expand due to balloon rupture. An 18-year-old patient was admitted with an increased right ventricular pressure and severe pulmonary regurgitation for scheduled cardiac catheterization. Angiography revealed a proximal stenosis of the left pulmonary artery (LPA). First, a prestenting was performed. Three months later he came back for planned percutaneous pulmonary valve implantation (PPVI). Because of the proximity of the right coronary artery (RCA) to the right ventricular outflow tract (RVOT) and thus a relatively short landing zone, the Melody valve had been doubly folded. During the inflation of the outer balloon, it ruptured. At this point, the Melody valve was still fixed to the inner balloon. A second catheter was placed through the Melody valve and successful valve implantation was possible. This procedure was difficult because to push the catheter through the partly inflated Melody valve, the inner balloon had to be slowly and simultaneously deflated. The final angiograms and pressure measurements showed a good functional result and absent pulmonary regurgitation. Open heart surgery could be avoided after incomplete Melody valve dilatation using the contralateral pulmonary artery as a safe rail.

Percutaneous catheter interventions via Glidesheath Slender in small children.

BACKGROUND: Catheterization in small children should be performed with the lowest diameter introducer sheaths to prevent permanent vessel damage. The objective of this study is to evaluate the clinical safety and efficacy of the Glidesheath Slender in small children. METHODS AND RESULTS: We present a group of 52 patients (male: n = 36) with median age 118.5 days (min. 3; max. 1302), median weight: 5.3 kg (min. 1.4; max. 14.0), median height: 60.5 cm (min. 39; max. 102), and median body surface area 0.28 m2 (min. 0.12; max. 0.63) in whom percutaneous catheter interventions (n = 55) were performed via a Glidesheath Slender. In 49 children, the intervention was performed from femoral access (artery n = 35; vein n = 14) in 2 from the axillary arterial access and in 1 from the jugular venous access. In all patients, the vessel access was obtained under ultrasound guidance. After the catheterization, the pulse on the peripheral arteries (posterior tibial artery or radial artery) was palpable in all patients, and no signs for vessel dysfunction were present. CONCLUSION: The Glidesheath Slender effectively reduces the outer sheath diameter for various types of interventions in small children by one French, reducing the risk of vessel complications (stenosis, occlusion). Interventions via Glidesheath Slender in small patients are safe and feasible and extend the transcatheter possibilities in small children with congenital heart diseases.

Spontaneous closure of arterio-venous pulmonary fistulas by redirection of hepatic venous blood 9 years after Glenn anastomosis in a 12-year-old girl.

We report on a 12-year-old girl with Ebstein's anomaly after a unidirectional Glenn procedure with surgical ligation of the proximal right pulmonary artery, who suffered from significant central cyanosis caused by multiple arterio-venous fistulas in the right lung. The continuity between the right pulmonary artery and the pulmonary trunk was restored with the use of radiofrequency perforation and consecutive covered stent implantation.

Percutaneous retrieval of a partially flared Melody valve.

We report on successful endovascular retrieval of an accidentally flared Melody valve in an adult patient with an indication for percutaneous pulmonary valve implantation. The Melody valve was removed through a 24 F sheath, introduced via the right jugular vein, and the urgent open-heart surgery was avoided.

Coarctation of the aorta-stenting via Glidesheath Slender in a newborn with recoarctation early after a Norwood operation.

In this article, we report on a newborn with hypoplastic left heart syndrome in whom recoarctation of the aorta was treated with a bare metal stent (Cook Formula 414 Stent) in the early postoperative period after a Norwood procedure. To reduce the risk for scarring and occluding the femoral artery the stent was implanted via 5F Glidesheath Slender sheath.

Measures of Heart Rate Variability in 24-h ECGs Depend on Age but Not Gender of Healthy Children.

Many methods computing heart rate variability (HRV) have been applied in studies in children. Not all of these methods have a comprehensive physiological interpretation, and not all of studies are in agreement with the Task Force Standards on HRV from 1996, and the New Joint Position Statement on the advances of HRV from 2015. The study aim was to analyse HRV in the 24-h ECGs of healthy children by the Poincare plots and Lomb-Scargle periodograms, and to follow proper HRV recommendations. Additionally, we investigated the associations between age, children's sex and measured HRV indices. One hundred healthy children, aged 3-18 underwent 24-h ECG Holter monitoring. HRV was analyzed by the Poincaré plots and spectral by Lomb-Scargle periodograms of RR intervals. The Mann-Whitney test was used to compare sex differences in HRV, the van Elteren's test was used to correct for the age-gender interaction, and non-parametric Spearman correlation was applied to analyse the association between age and HRV indices. None of the HRV measures differed significantly between boys and girls. None of the HRV indices was modified by the age-gender interaction. There were statistically significant associations of age with measures of ultra-low (rho = 0.42; p < 0.0001), very low (rho = 0.35; p = 00004) and low (rho = 0.30; p = 0.0028) frequency powers, the ratio of the low to high frequency power (rho = 0.38; p = 0.0001), indices of long-term (SD2; rho = 0.37; p = 0.0002) and total (SDNN; rho = 0.33; p = 0.0008) HRV, and the contribution of the long-term HRV to total HRV (CL; rho = 0.32; p = 0.0012). In general, HRV parameters derived from the analyses of Poincaré plots and Lomb-Scargle periodograms appear not to be affected by gender, however, most of them increase with age in the 24-h ECG recordings in healthy children.