Experience with implantation of Select Secure® leads in paediatric patients

Objective: In this study, we aimed to investigate the safety, feasibility and efficacy of Select Secure^® lead in a pure paediatric cohort and to present our experience with implantation technique, complications, and acute and midterm performance of the lead.Method: From 2014 to 2020, 42 consecutive paediatric patients underwent a cardiac device implantation with Select Secure^® lead system. Patient demographics, implantation technique, and locations, sensing and pacing characteristics, impedances and any complications at implant and follow-up were investigated.Results: The mean age and weight of patients were 11.2 ± 3.5 years and 34.7 ± 14.8 kg, respectively. A total of 78 Select Secure^® leads were successfully implanted. All ventricular leads were successfully anchored to the right ventricular midseptum. Implantation procedures were uneventful in all patients. We showed that atrial and ventricular sensing, pacing thresholds, and impedance measurements did not change significantly and that adequate pacing parameters were achieved in our patients during a median follow-up period of 47 months (4 - 68). Atrial and ventricular sensing, pacing thresholds and impedance measurements remained almost the same during the study period.Conclusions: In this study, we found that the Select Secure^® transvenous pacing system was safe and feasible in paediatric patients without any major complications and with very stable electrical performance in the acute and midterm period.

Risk Factors Associated with Ascending Aortic Aneurysms and Aortic Elasticity Parameters in Children with a Bicuspid Aortic Valve

Aneurysms of the ascending aorta are frequently found in patients with a bicuspid aortic valve (BAV). This study assessed the risk factors of ascending aortic aneurysms and aortic elasticity in children with BAV. The study included 66 patients with no history of transcatheter intervention or surgical procedure who had been diagnosed with isolated BAV. Echocardiographic, blood pressure, and pulse measurements were obtained for all patients. The BAVs were classified as described by Sievers et al. (J Thorac Cardiovasc Surg 133:1226-1233, 2007), and aortic elasticity parameters were calculated using various formulas. The patients were divided into groups with and without cusp fusion, aortic stenosis (AS), aortic regurgitation (AR), or mixed lesions; the groups were then compared. The mean patient age was 10.43 ± 3.91 years; 15%he patients had no AS or AR, 33% had both AS and AR, 17% had AS alone, and 35% had AR alone. The most common type of BAV was type 5, and the ascending aorta z-scores were higher in children with mixed lesions and without a cusp fusion. Aortic distensibility (AD) was significantly higher, and the stiffness index was significantly lower, in patients with an ascending aorta z-score > 4. The ascending aortic z-scores were higher in the no-fusion and mixed lesion (AS + AR) groups, especially those originating from post-stenotic dilation due to AS. The AD was increased in patients with an ascending aorta z-score > 4. Patients should thus be monitored closely for dissection risk, and preventive medical treatment should be started early in those with AS without cusp fusion.

A stereological study on calculation of volume values regarding lumbosacral segments of quails

In the study, total segment, grey matter and white matter volume values of lumbosacral segment of spinal cord in quails (Coturnix coturnix japonica) were stereologically examined. Regardless of sex, six adult quails were used as material. After the materials were perfused, they were dissected and their spinal cords were uncovered. Tissue samples were taken from each lumbosacral segment of spinal cord. After the tissue fixation process, 6-7 sections having a 5-µm thickness were separated in every 50th section as from the first section, where the tissue was seen, among tissue samples of each segment. These segments were stained with haematoxylin-eosin staining. They were photographed via a microscope. By using the Cavalieri's principle, the volume values of both the total segment, grey matter (GM) and white matter (WM) in each lumbosacral segment were separately calculated. All these calculations were performed by using SHTEREOM 1.5 program. As a result, total volume, grey matter and white matter volume values of lumbosacral segments and white matter/total volume, grey matter/total volume, and grey matter/white matter volume fractions were obtained.

A morphological and stereological study on calculating volume values of thoracic segments of geese

BACKGROUND

In this study, the total volume of the thoracic segments of the spinal cord and volume densities of grey matter and white matter were examined by using stereological methods in adult geese having a weight of 3-4 kg.

MATERIALS AND METHODS

Ten geese were used as material without sex discrimi- nation. All animals were perfused with 10% formaldehyde. In addition, after perfusion, the geese were kept in 10% formaldehyde for 1 week. Afterwards, thoracic spine was removed and thoracic part of spinal cord was excised. 5 μm thick sections were taken from these tissue samples by microtome. The cross- sectional series were obtained by sampling from each segment at 250th section. Twelve sections were taken from tissue specimens of every segment. The sections were stained by using haematoxylin-eosin and photographed on a microscope.

RESULTS

By using the Cavalieri's Principle, the volume densities (volume fractions) of thoracic segments of spinal cord, volume of white matter, and volume of grey matter in segments were calculated.

CONCLUSIONS

In the study, total volume of the thoracic segment, volume of white matter, and the volume of grey matter, and the ratio of these volume values to each other were calculated. The SHTEREOM 1.0 software was used for calculating the volume of section specimens.

In vitro effects of lidocaine hydrochloride on coronary artery bypass grafts

AIM

Coronary artery bypass grafting (CABG) is one of the most common procedures performed to improve blood supply to myocardium. The characteristics of grafts, mechanical stress and pharmacological agents have substantial influence on the short and long term graft patency. Lidocaine is among the most frequently used antiarrhythmic agents perioperatively. The aim of this study was to evaluate the in vitro effects of lidocaine on internal mammarian artery (IMA), radial artery (RA) and saphenous vein (SV) grafts.

METHODS

Using standard tissue bath techniques, responses to increasing concentrations of lidocaine hydrochloride were obtained, in segments of IMA, RA and SV grafts. Twenty patients were enrolled in the study with a total number of 48 grafts (16 for IMA, RA and SV grafts each). In vitro lidocaine concentrations between 10(-9)M and 10(-3.5)M were studied to represent therapeutic plasma concentration of 1.5-5 mcg/mL.

RESULTS

In IMA and RA grafts, lidocaine hydrochloride caused vasodilatation (40.5±1.9% and 39.1±2.6 % respectively) at concentrations between 10(-9) to 10(-7.5) M while causing a dose dependent vasoconstriction response at concentrations above 10(-7.5) M. In SV graft samples, lidocain hydrochloride caused vasodilatation (24.4±1.9 %) at concentrations between 10(-9) to 10(-7) M while causing dose dependent vasoconstriction at concentrations above 10(-7) M. For vasoconstriction effect, mean±SD values for E(max) were calculated as: 120.1±6.6% in IMA, 83.35±5.06% in RA, and 154.0±13.8% in SV. The vasoconstriction in the SV samples was higher than in the RA and IMA. The mean ±SD LogEC(50) values were -5.15±0.27, -5.76±0.11 and -5.56±0.19 for SV, IMA and RA grafts respectively.) There was a statiscally significant differences in the Log EC(50) values between SV, IMA and RA (P<0.005)

CONCLUSION

Based on the results of our study, we conclude that, increasing doses of lidocaine in the perioperative period may cause vasospasm in IMA, RA and SV grafts. Thus, avoiding high doses may have a role in improving perioperative and long term mortality.

Acute radiation effect in the brain in infant rats: Neurocognitive and histopathological examination

PURPOSE

The aim of the present study was to evaluate the radiation-induced cognitive dysfunction and the radioprotective effect of amifostine (AMI) in the brain of infantile rats.

METHODS

Thirty 2-week-old rats were randomly assigned into 3 groups of 10 rats each. Group 1: control (CONT), group 2: radiation alone (RT), and group 3: AMI before radiation (AMI+RT). The rats in the RT and AMI+RT groups were irradiated individually with a single dose of 20 Gy. All animals were evaluated by using the Morris water maze test to evaluate of their cognitive functions. Histopathological analyses of the hippocampus were also carried out after euthanasia.

RESULTS

The study showed that the place navigational function and the spatial probe test were not significantly different between the groups.

CONCLUSION

It can be said that it is very important to determine when the radiation-induced brain injury is formed. From a clinical perspective, the patients can be intervened before irreversible functional deficits are formed and may be amenable to treatment.

Morphology of the venous system of the heart in the van cat

Morphology of the veins draining the heart was studied in the Van cat. Veins draining the heart were the great cardiac vein, the middle cardiac vein, the right cardiac veins and the smallest cardiac veins. No anastomosis was observed between the terminal branches of the paraconal interventricular vein and the subsinuosal interventricular vein. The coronary sinus was formed by the great cardiac vein and the middle cardiac vein. The origins of the right cardiac veins had significant variations. The right semicircumflex vein was observed in three (50%) cats, and it terminated at the middle cardiac vein.

Reiter syndrome following intracavitary BCG administration

BCG vaccine was given intravesically to a patient with bladder tumour. After the fifth dose she developed bilateral conjunctivitis, painful swelling in her wrist, dysuria and arthritis in her left knee and right metacarpophalangial joints. The diagnosis was Reiter syndrome and is the second case in the literature.

The role of H1- and H2-receptors in the effect of compound 48/80 in the asphyxiation and body temperature of mice

Contribution of histamine H1- and H2-receptors to the effect of compound 48/80, a potent histamine releaser, upon asphyxiation and body temperature in mice was investigated in the present experiments. Compound 48/80 showed an apparent protective potency against hypoxia and significantly prolonged the latencies for convulsions and death in a dose-dependent manner. Compound 48/80 also decreased the body temperature, which was in relation with the antihypoxic effect. Both the H1-receptor antagonist, dimethindene, and the H2-receptor antagonist, ranitidine, attenuated the hypothermic effect of compound 48/80, indicating the involvement of central histamine through both the H1- and H2-receptors. Ranitidine had no effect on the protective effect of compound 48/80 against hypoxia-induced lethality, whereas dimethindene completely antagonized it. These results suggest that the protective effect of compound 48/80 against hypoxia is mediated through histamine H1-receptors and is not related to its ability to induce hypothermia.