Individual programming of current multiprogrammable pacemakers : Still unsatisfactory?

BACKGROUND

Pacemaker (PM) technology has developed tremendously in recent decades. We evaluated the extent of individual programming in current PMs.

METHODS

Over a 7-month period in 2016, all deceased persons taken to the Rostock crematorium were prospectively screened for cardiac implantable electronic devices (CIEDs) and these were interrogated in situ. Programming of patient data, leads, and study parameters including mode, lower rate, upper tracking or sensor rate (UTSR), ventricular refractory time, sleeping function, hysteresis, and PM-mediated tachycardia intervention were analyzed and compared with delivery settings. Alterations in atrial/ventricular capture management and atrial/ventricular sensing assurance as well as changes in sensitivity and lead output were evaluated.

RESULTS

We examined 2297 subjects, of whom 154 (6.7%) had CIEDs, with 125 (81.2%) being PMs. Finally, 72 (57.6%) PMs were eligible for analysis with an operation time of 31.0 ± 27.0 months. We excluded 28 (18.2%) implantable cardioverter defibrillators (ICDs), 51 (41%) PMs presenting elective replacement indicator (ERI), two (1.6%) PMs with programming to insufficient function prior to death, and the left ventricle parameter of one (1.4%) cardiac resynchronization therapy pacemaker (CRT-P); further one CIED (0.6%) was not contactable. PMs offered in mean 75.2% of study parameters thereof 88.0% were to adjust manually, whereof 49.3% stayed unchanged to delivery mode. Lead output, UTSR, lower rate, and mode were the most frequently changed parameters (>85.7%, 65.3%, 54.2%, and 52.8%, respectively) compared with unmodified ventricular refractory time and hysteresis (91.7% and. 85.4%, respectively); 2.8% of PMs had out-of-the-box settings. The most frequent personalized data were last (88.9%) and first name (73.6%), while atrial and ventricular serial lead numbers were rarely entered (18.2% and 23.4%, respectively).

CONCLUSION

The programming possibilities of PMs have advanced greatly. Nonetheless, improvements in individual PM programming are still needed as demonstrated by the findings in this study, e.g., PMs with manufacturer settings and lack of individual data.

Fracture generation in human vertebrae under compression loading: The influence of pedicle preservation and bone mineral density on in vitro fracture behavior

BACKGROUND

Fractured vertebral bodies are a common and wide spread health issue.

OBJECTIVE

The purpose of this study was to develop a standardized method to experimentally generate compression fractures in vertebral bodies. The influence of the pedicles has been investigated with regards to the fracture behavior. The correlation between bone mineral density (BMD), the cause of fractures and the fracture behavior was investigated.

METHODS

Twenty-one fresh frozen human lumbar spines were examined for bone mineral density (BMD) by means of quantitative computed tomography (qCT). All soft tissue was removed, vertebrae were carefully separated from each other and the exposed cranial and caudal endplates were covered with a thin layer of resin to generate a plane and homogeneous surface. A total of 80 vertebral bodies were tested until fracture.

RESULTS

A good positive correlation was found between BMD, fracture compression force and stiffness of the vertebral body. No significant differences were found between the fractures generated in vertebral bodies with and without pedicles, respectively.

CONCLUSIONS

Our model represents a consolidation of already existing testing devices. The comparative measurement of the BMD and the fracture behavior shows validity. In contrast to other authors, the force was applied to the whole vertebral body. Furthermore the upper and lower plates were not parallelized and therefore the natural anatomic shape was imitated. Fracture behavior was not altered by removing the pedicles.

Unusual head injury by a forklift vehicle

A case of an unusual head injury by a forklift vehicle is presented.

Erste-Nacht-Effekt bei schlafbezogenen Atmungsstörungen

Bekannterweise existiert bei Patienten mit dokumentiertem obstruktiven Schlafapnoe-Syndrom (OSAS) eine Nacht-zu- Nacht-Variabilität der Apnoen/Hypopnoen während der nächtlichen Polysomnografie (PSG). Diese könnte dazu führen, erkrankte Patienten nicht oder nicht rechtzeitig zu erkennen und angemessen zu behandeln und somit ein erhöhtes Risiko für eine massive Verschlechterung des OSAS und/oder Folgeerkrankungen kardiologischer und/oder neurologischer Art zu provozieren. In dieser Studie untersuchten wir, ob bzw. inwieweit die Möglichkeit besteht, dass diese Variabilität aufgrund der fortschreitenden Mittelkürzungen im Gesundheitswesen dazu führen kann, OSAS-Patienten nicht diagnostizieren zu können, zu spät zu behandeln oder unbehandelt zu lassen. Die Untersuchung erfolgte intraindividuell an einer Gruppe von 100 OSAS-Patienten (17 weiblich). Alle Studienteilnehmer wurden polysomnografisch sowohl in der ersten als auch in der zweiten Nacht untersucht und mussten alle zur OSASDiagnose notwendigen Kriterien aufweisen. Das Untersuchungsdesign sah den Vergleich der beiden Diagnosenächte vor. Die Überprüfung ergab einen signifikanten Unterschied (p < 0,001). Bei 72% kam es in der zweiten PSG-Nacht zu einer Erhöhung des AHI. In unserer Untersuchung zeigte sich, dass die nächtlichen Apnoen/Hypopnoen beim OSAS zwischen erster und zweiter PSG-Nacht so stark variieren, dass die Erkrankung bei 40% aller Fälle nach nur einer PSG-Nacht zu einer Fehldiagnostik führen würde.

Delineation of Subregions in the Early Postnatal Human Cerebellum for Design-Based Stereologic Studies

Recent design-based stereologic studies have shown that the early postnatal (<1 year of age) human cerebellum is characterized by very high plasticity and may thus be very sensitive to external and internal influences during the first year of life. A potential weakness of these studies is that they were not separately performed on functionally relevant subregions of the cerebellum, as was the case in a few design-based stereologic studies on the adult human cerebellum. The aim of the present study was to assess whether it is possible to identify unequivocally the primary, superior posterior, horizontal, ansoparamedian, and posterolateral fissures in the early postnatal human cerebellum, based on which functionally relevant subregions could be delineated. This was tested in 20 human post mortem cerebellar halves from subjects aged between 1 day and 11 months by means of a combined macroscopic and microscopic approach. We found that the superior posterior, horizontal, and posterolateral fissures can be reliably identified on all of the specimens. However, reliable and reproducible identification of the primary and ansoparamedian fissures was not possible. Accordingly, it appears feasible to perform subregion-specific investigations in the early postnatal human cerebellum when the identification of subregions is restricted to crus I (bordered by the superior posterior and horizontal fissures) and the flocculus (bordered by the posterolateral fissure). As such, it is recommended to define the entire cerebellar cortex as the region of interest in design-based stereologic studies on the early postnatal human cerebellum to guarantee reproducibility of results.

Gene expression analysis of growth factor receptors in human chondrocytes in monolayer and 3D pellet cultures

The main goal of cartilage repair is to create functional tissue by enhancing the in vitro conditions to more physiological in vivo conditions. Chondrogenic growth factors play an important role in influencing cartilage homeostasis. Insulin‑like growth factor (IGF)‑1 and transforming growth factor (TGF)‑β1 affect the expression of collagen type II (Col2) and glycosaminoglycans (GAGs) and, therefore, the targeted use of growth factors could make chondrogenic redifferentiation more efficient. In the present study, human chondrocytes were postmortally isolated from healthy articular cartilage and cultivated as monolayer or 3D pellet cultures either under normoxia or hypoxia and stimulated with IGF‑1 and/or TGF‑β1 to compare the impact of the different growth factors. The mRNA levels of the specific receptors (IGF1R, TGFBR1, TGFBR2) were analyzed at different time points. Moreover, gene expression rates of collagen type 1 and 2 in pellet cultures were observed over a period of 5 weeks. Additionally, hyaline‑like Col2 protein and sulphated GAG (sGAG) levels were quantified. Stimulation with IGF‑1 resulted in an enhanced expression of IGF1R and TGFBR2 whereas TGF‑β1 stimulated TGFBR1 in the monolayer and pellet cultures. In monolayer, the differences reached levels of significance. This effect was more pronounced under hypoxic culture conditions. In pellet cultures, increased amounts of Col2 protein and sGAGs after incubation with TGF‑β1 and/or IGF‑1 were validated. In summary, constructing a gene expression profile regarding mRNA levels of specific growth factor receptors in monolayer cultures could be helpful for a targeted application of growth factors in cartilage tissue engineering.

Alcohol-related diseases

Alcohol abuse and dependence are serious medical and economic problems in Western countries. Brain changes encountered in alcoholism are manifold and encompass brain atrophy, selective neuronal loss, astroglial, and microglial changes. Alcohol-related disorders are complex multifactorial disorders where the interaction of multiple genes and environment plays an important role in the pathogenesis.

Neurotoxicology and drug-related disorders

Neuropsychiatric disorders caused by toxic substances pose a great diagnostic challenge due to the large variety of changes caused in the central and peripheral nervous system. The pathogenetic mechanisms at work are multifaceted and partly not solved. In human drug abusers (cannabis, opiates, cocaine, amphetamines, methamphetamine and "designer drugs"), a broad spectrum of central nervous system alterations are observed including infarction, intracerebral and subarachnoidal hemorrhage, hypoxic-ischemic leukoencephalopathy, infections, neuronal loss, specific astroglial and microglial reaction patterns, and vascular changes, including the endothelial cell as well as the basal lamina.

[Unexpected Complications in the Withdrawal Treatment of the Research Chemical AH-7921]

We describe the case of a young male patient who had consumed the morphine-like substance AH-7921 which is available via the internet. He was initially admitted to hospital because of obstipation and presented within a day of inpatient treatment for the first time with a generalized tonic-clonic epileptic seizure with subsequent urinary retention. Within a few hours, the patient then also developed bradycardia, while at the same time describing symptoms of physical opioid withdrawal which gradually deteriorated within the following hours. We initiated a treatment with buprenorphine which resulted in a considerable reduction of withdrawal symptoms, so the patient could be discharged from hospital.

[Autopsies for anatomical teaching and training in clinical forensic medicine]

BACKGROUND

Clinical forensic medicine does not only entail examination of patients after physical violence but also the option of clinical autopsies, e.g. after non-notifiable complications of medical interventions, after fatalities closely following medical interventions or fatalities as a result of injuries when the public prosecutor decides not to order a medicolegal autopsy. Based on this routine the Institute of Forensic Medicine at the University of Rostock offers a training course in topographical anatomy to physicians for further training in interventional and surgical disciplines.

METHODS

At the beginning of autopsies the participants can explore the approaches of interventional puncture techniques as well as surgical techniques and the basic topographical anatomy in small groups of 2-4 persons under the supervision of forensic examiners. The format is essentially oriented to the early further training period but fulfils the requirements for the exploration of complex operative techniques. The course was adapted for physicians and offered separately to students. The explorations are performed manually or by support with autopsy instruments.

RESULTS

The courses offer an ideal room for individual, discipline-specific topics and result in a great benefit for all participants. A statistical assessment can only be achieved with a larger number of participants.

CONCLUSION

Making autopsy rooms available for teaching and further training represents an additional feature to the profile of clinical forensic medicine. Lessons in topographical anatomy provide a great benefit for patient safety. It seems to be important to offer the opportunity to address individual interests in a closed meeting to consolidate skills and abilities in a non-judgemental environment. The post-mortem examiners have to ensure that the autopsy is carried out lege artis. Basic ethical principles and all regulations from an accredited scope have to be adhered to.

Histologic spectrum of the cardiac conducting tissue in non-natural deaths under 30 years of age: an analysis of 43 cases with special implications for sudden cardiac death

In the past, histological findings of the cardiac conduction system or its adjacent structures, such as filiform fibers at the transition from bundle of His to bundle branches, connective tissue at the apex of the ventricular septum, or fibromuscular alterations of the arteries has been considered as a cause of death. However, the prevalence of such findings in a healthy population has been rarely analyzed systematically. In the present study, the morphology of the cardiac conduction system of 43 heart-healthy individuals who died of non-natural causes (ages 0 to 30 years) was investigated. In a high percentage of cases, connective tissue at the apex of the ventricular septum (97.7%), filiform fibers at the transition from bundle of His to the bundle branches (27.9%), and fibromuscular proliferations of the sinoatrial node artery (41.9%), and the AV-node artery (39.5%) could be detected. Based on our observations, these alterations should not be considered as a pathologic entity or as a cause of death.

Alterations of neuronal precursor cells in stages of human adult neurogenesis in heroin addicts

BACKGROUND

Adult neurogenesis has been shown to occur throughout life and different brain pathologies were demonstrated to be associated with altered neurogenesis. Here, an impact of heroin addiction on neurogenesis in humans is hypothesised.

METHODS

Post mortem hippocampal specimens of drug addicts with known heroin abuse and a group of non-addictive control subjects were analysed, using antibodies indicating different stages of neurogenesis. The subgranular zone of the dentate gyrus was examined qualitatively and quantitatively.

RESULTS

The data indicate (i) a decreased number of neural precursor cells, (ii) accompanied by low rates of proliferation and (iii) a marked loss of dendritic trees in targeting cells in heroin fatalities. (iv) The age-dependent increase of differentiating cells in the healthy controls was not observed in the addicts. Additionally, double immunofluorescence labelling indicated the precursor nature of Musashi-1 positive cells in the human subgranular zone of the dentate gyrus.

CONCLUSIONS

Present data firstly demonstrate the influence of drug addiction with known heroin abuse on different developmental stages of progenitors in the dentate gyrus. The patterns of antibody staining suggest a distinct inhibition of neurogenesis at the stage of neural precursor cells and revealed morphological changes in targeting cells in cases of heroin addicts as compared to healthy controls. These alterations could be considerable for memory and cognitive deficits as well as addictive behaviour in chronic drug abusers and may give rise to specific pro-neurogenic therapies.

Distinction between forensic evidence and dermatological findings

The external examination after death requires knowledge in forensics/pathology, dermatology, as well as associated diseases and age-related alterations of the skin. This article highlights some findings with forensic evidence versus dermatological findings. The lectures in forensic medicine should be structured interdisciplinarily, especially to dermatology, internal medicine, surgery, pathology, and toxicology in order to train the overlapping skills required for external and internal postmortem examinations.