Few Insights on the problem of COVID-19

The recent Coronavirus 2019 outbreak took the world by surprise and called for global drastic measures. At this early point in the timeline of the pandemic, several questions remain open until the results of large scale studies become available. This article offers few insights on scattered issues; including the clinical characteristics, pathology and diagnosis, as well as treatment perspectives and public health approach. Focusing healthcare resources on necessary treatment and prevention and combining efforts for developing feasible solutions will be decisive for time needed to achieve worldwide containment (Tab. 1, Ref. 23). Keywords: COVID-19, Coronavirus 2019, pandemic, public health.

Rationale Use of Neutrophil-to-lymphocyte ratio for early diagnosis and stratification of COVID-19

Coronavirus disease is caused by a virus that is the cause of a potentially fatal disease worldwide. Coronavirus is a pathogen that primarily affects the human respiratory system. Coronavirus 2019 (COVID-19) has been named WHO since February 11, 2020. The first cases of COVID-19 were reported in December 2019. In January 2020, COVID-19 infection was identified in hospitalized patients in Wuhan, China. We analyze the role of neutrophil-lymphocyte ratio (NLR) in viral infection with special emphasize on novel corona virus disease-COVID-19. NLR may be used for early detection and may reflect progression to the more severe illness leading to SARS-CoV-2. In the mini review we investigate the use of NLR as a surrogate marker for diagnosis and stratification of COVID-19.Clinical symptoms such as pneumonia, acute respiratory distress syndrome, acute heart damage have led to death. In some cases, multiple inflammations have been observed. Treatment with interferon inhalation showed no clinical effect and the condition worsened instead (Tab. 5, Fig. 1, Ref. 18). Keywords: neutrophil-to-lymphocyte ratio, corona virus SARS-CoV-2, COVID-19.

Adipose derived mesenchymal stem cells harvesting

BACKGROUND

The lipografting is increasingly used in the field of plastic surgery. Widely used harvesting technique of fatderived stem-cells is lipoaspiration. There exist two big streams of fat harvesting for lipografting: mechanical liposuction and manual liposuction.

METHODS

Two harvested specimens were compared in this prospective blind study in the means of stem-cells viability and their ability to grow in cell-cultures. Techniques to compare were: manual lipoaspiration with 50 ml syringe and WAL (water-jet assisted liposuction).

RESULTS

Twenty specimens from ten patients were investigated in the tissue bank. There were no differences in the amount of live stem-cells between two groups. Also no differences were found between both harvesting techniques in the mean of cell ability to grow in cell-cultures.

CONCLUSION

It can be concluded that there are no statistically significant differences in the number, vitality and viability of stem cells when comparing two ways of mesenchymal stem cell collection, both manual and machine sampling (WAL). When cultured in vitro, both samples collected from each patient also appeared to be able to multiply with no statistical differences (Tab. 2, Fig. 2, Ref. 18).

The effect of GnRH agonists on angiogenesis and its implications for the myocardium in patients with cardiac risk

Gonadotropin-releasing hormone agonists were described as anti-angiogenic factors in tumors. Simultaneously they were associated with increased cardiovascular risk in patients treated for prostate cancer, especially in those with preexisting cardiac disease. Studies aiming to elucidate the mechanisms by which androgen deprivation therapy causes cardiovascular effects are rare. We believe that gonadotropin-releasing hormone agonists can impair myocardial angiogenesis. That, in patients with myocardial disease can deepen hypoxia, significantly worsen the condition of the myocardium, and therefore increase the risk of cardiac failure. Careful assessment of the myocardial status and consequent timing and typing of therapy can minimalize the adverse effects. Ideally through close cooperation between cardiologists and oncologists (Fig. 1, Ref. 25). Keywords: angiogenesis, cardiovascular risk, follicle stimulating hormone, GnRH agonist, testosterone.

Artificial intelligence in service of medicine

The race to make the dream of artificial intelligence a reality comes parallel with the increasing struggle of health care systems to cope with information overload and translational pressure. It is clear that a shift in the way data is generated requires a shift in the way they are processed. This is where AI comes with great promises to solve the problem of volume versus applicability of information in science. In medicine, AI is showing exponential progress in the fields of predictive analysis and image recognition. These promises however, come with an intricate package of ethico-social, scientific and economic implications, towards which a reductionist approach leads to distorted and dramatic predictions. All this, in a time when the growing pressure on healthcare systems towards defensive medicine begs the question of the true need for AI for good medical practice.This article examines the concept and achievements of AI and attempts to offer a complex view on the realistic expectations from it in medicine, in the context of current practice (Ref. 38). Keywords: algorithms, artificial intelligence, image recognition, neural networks, predictive analysis.

Are GnRH and FSH potentially damaging factors in the cardiovascular system?

In the physiological view the human cardiomyocytes express receptors of gonadotropin-releasing hormone and follicle-stimulating hormone. The local effects of these hormones in the heart are related also to some interstitial cells, such as endothelial cells with follicle-stimulating hormone receptors and immune cells with gonadotropin-releasing hormone receptors. The administration of androgen deprivation therapy in patients with prostate cancer is associated with increased incidence of cardiovascular complications. It is suggested that negative action of this therapy on cardiovascular system is due to the loss of testosterone but also levels of gonadotropin-releasing hormone and follicle-stimulating hormone are changed by therapy. In this article we review the literature to date with an emphasis on recent investigation focused on potential role of abnormal gonadotropin-releasing hormone and follicle-stimulating hormone levels induced by gonadotropin-releasing hormone agonists on the cardiovascular risk. These facts exacerbate the complexity of specific hormone and cell relationships within heart and vessels. Androgen deprivation therapy reveals the physiological relationships between hormones and specific tissues that are not part of the endocrine system.

Androgen deprivation therapy and cardiovascular complications

Cardiovascular complications associated with the use of antiandrogens have already been known for some time. Based on the results of the latest meta-analyses and clinical studies published in the last few years, the attention of the scientific community is focused on the deleterious cardiovascular effects of gonadotropine-releasing hormon agonists in context of the androgen deprivating therapy. The cardiac toxicity is a problem especially in patients with preexisting cardiovascular comorbidities. Increased arterial wall thickening along with endothelial dysfunction has been observed in patients with descreased androgens levels in the peripheral blood. The treatment with gonadotropine-releasing hormon agonists may disrupt the intracellular concentration of calcium ions and the contractile process and potentially result in pathological remodelling of heart. Here, we give several possible mechanisms of action of gonadotropine-releasing hormon agonists on the cardiovascular system that may be a potential explanation of the clinical observations (Ref. 44).

Prevalence of cleft lip and palate in western Slovakia in the years 2001-2007

OBJECTIVES

The aim of this study was to investigate the prevalence of orofacial clefts (OC) in live newborns from 2001 to 2007 in Western Slovakia and correlate their occurrence with a number of relevant seasonal and geographical factors and epidemiological trend of this condition. In this study we used retrospective active survey collecting clinical data of 220 children with OC registered and operated at the cleft centre in Bratislava. Our study group included 67 patients from Bratislava region and 151 patients from the remaining Western Slovakia (Nitra, Trnava, Trenčín regions). Data of live births was obtained from Health Statistics of the Slovak Republic.

RESULTS

Total incidence (TI) of 1.49/1000 live births (LB) in the region of Western Slovakia in 2001-2007 marked a decrease of prevalence compared to 1.64/1000 LB in the years 1985-2000. Bratislava region dominated in total prevalence of 1.82/1000 LB compared to the rest of Western Slovakia regions with 1.37/1000 LB. Most observed cleft type was the CP with 38.6 % frequency, followed by CLP with 35.5 % and CL with a frequency of 24.1 %. The frequency of AM with 1.82 % was the lowest.

CONCLUSION

The results showed that the frequency risk rate of a birth of a child with OC was 1 to 671 LB in Western Slovakia. The data proved a higher prevalence of OC in Bratislava region with 1 child with this type of congenital anomaly to 549 LB compared with 1 child with OC to 730 LB in the rest of the Western Slovakia regions (Tab. 7, Ref. 16).

Perspectives and complexity of an experimental cancer study. the secrets of tumorigenesis. (To the Gupta's, Chaffer's and Weinberg's "perspectives" and to the nurse's "horizons")

We would like to add to the "mysteriousness", our observations from the application of "identical" BP6 cells either intraperitoneally or subcutaneously. In connection with the concept that tumor development is not only a portrayal of cells proliferation, we could presume that different "environment" will result in structurally different tumors. Morphological differences observed are not significant, but they are present (Fig. 2, Ref. 12). Full Text (Free, PDF) www.bmj.sk.

Diastolic blood pressure as a major determinant of tissue perfusion: potential clinical consequences

Blood pressure measuring represents a routine investigation in general medicine. In the last decades large studies have determined average blood pressure values all around the world. Large clinical trials have shown that blood pressure reduction irrespective of the used type of therapeutic intervention reduces mortality. Based on the outcomes of these trials current guidelines for hypertension encourage more "aggressive" hypertension treatment compared to recommendations from the past. In clinical practice blood pressure is sometimes reduced even below normotensive values (at least in comparison with pre-treatment levels). However there is evidence that achieving too low levels of diastolic blood pressure during antihypertensive treatment has undesirable effects. Especially in the elderly a diastolic blood pressure reduction below 70 mm Hg should be avoided, because it is associated with increased mortality. A possible explanation of this phenomenon could be that antihypertensive treatment disequilibriates the balance between sufficient perfusion pressure and arteriolar vasodilation, both of which are required for adequate tissue perfusion. Impaired microcirculation, especially in the coronary bed may account for the increased mortality in hypertensive patients with low diastolic blood pressure levels. Thus we support the idea of cautious blood pressure reduction in the elderly. Furthermore, we suggest, that monitoring the level of tissue perfusion in treated hypertensive patients might help to provide individually tailored therapy (Fig. 1, Ref. 9). Full Text (Free, PDF) www.bmj.sk.

Timing of primary lip repair in cleft patients according to surgical treatment protocol

OBJECTIVES

The goal of this article is to focus on the results of meeting the primary lip repair timing in compliance with the surgical treatment protocol used at the Cleft Center, Bratislava.

METHODS

Retrospective analysis of 45 initial lip repairs among all cleft operations in a period of 3 years (2006-2008). The object of the analysis was the "day of surgery after birth". The defined time period was that of 90th-180th day (3-6 months) for the initial lip surgery according to surgical protocol. Histories of patients who underwent surgery before the 90th or after the 180th day were examined.

RESULTS

40 patients (89%) underwent primary lip surgery in the defined time period of 3-6 months following the surgical treatment protocol. 5 patients (11%) underwent primary lip surgery at a later age than 6 months only because of pediatric reasons: recurrent bronchopneumonia (3 patients), recurrent respiratory infections plus prematurity (1 patient) and sideropenic anaemia (1 patient). There were no operative and postoperative surgical or anesthesiological complications. There were only serious pediatric reasons for surgery delays.

CONCLUSION

The determined timing of primary lip closure in 3-6 months is considered adequate according to the achieved results. In most of the cases this timing offers reliable conditions to perform early surgery in baby patients. The successfull realisation of the primary lip repair in the defined time period of 3-6 months is very important for proper timing of subsequent surgeries as well as for that of consecutive completion of treatment (Tab. 1, Fig. 1, Ref. 8).

Dangerous versus useful hypertension (a holistic view of hypertension)

The authors aim to offer a holistic view on hypertension and its treatment. Their approach is fairly confrontational, particularly by suggesting that hypertension may play a role in optimizing the blood flow and enhancing oxygen delivery. An increase in blood pressure brings about a threat of catastrophes. Therefore hypertension might be considered as either a subsequent complication, or an inevitable adaptation. When changes of many complicated and complex mechanisms result in retention of sodium and water, then the treatment of this condition is so far the most logical conclusion, and possibly beneficial to the patient. This can be done by influencing the peripheral resistance or the load of vascular bed. However, in some cases a moderate overfilling of the system with no increase in heart rate could be interpreted as an optimal solution for organism that does not necessarily need to be medically treated. This may apply especially to young hypertensive patients, and in cases when no catastrophe is assumed to take place. Lowering the blood pressure to average population levels in each case, especially by means of aggressive therapy may not necessarily lead to improved tissue perfusion. A decrease in blood pressure reduces the risk of catastrophes. However, on the other hand, it can deteriorate the tissue perfusion and cause unfavorable long-term consequences.

Does incorporation of gene for green fluorescent protein in BP6 fibrosarcoma tumor cells depress their intraperitoneal growth in rats? (In honour of Nobel Prize laureates 2008--Osamu Shimomura, Martin Chalfie, Roger Y. Tsien)

This manuscript was in honour of Nobel Prize in chemistry "for the discovery and development of the green fluorescent protein, GFP" to Osamu Shimomura, Martin Chalfie, and Roger Y. Tsien, simultaneously a brief information about experience with GFP in experimental tumorigenesis used this study is also presented. The experimental data have showed that BP6 cells incorporated with GFP gene have had smaller ability to induce both experimental intraperitoneal and subcutaneous tumor process. It was anticipated that incorporation of GFP gene might change physiological properties of cytoskeleton and worsen adhesive characteristics of tumor cells. It was also supposed that aftertime GFP will enable to monitor proliferation of cells not only within experimental work, but also in human medicine. GFP could help (supposedly) as reporter of proliferation, but also can serve as "target" for guide of tumorigenesis inhibiting substances. These ideas which are consequences of our experiments we append as congratulation to Nobel Prize in chemistry of the 2008 (Fig. 2, Ref. 44). Full Text (Free, PDF) www.bmj.sk.

Regression of left ventricular hypertrophy and aortic remodelling in NO-deficient hypertensive rats: effect of L-arginine and spironolactone

AIM

We investigated, whether the substrate for nitric oxide (NO) formation -L-arginine - and the aldosterone receptor antagonist - spironolactone - are able to reverse alterations of the left ventricle (LV) and aorta in N(omega)-nitro-L-arginine methyl ester (L-NAME)-induced hypertension.

METHODS

Six groups of male adult Wistar rats were investigated: controls after 4 and 7 weeks of experiment, rats treated with L-NAME for 4 weeks and three recovery groups: spontaneous-reversion (4 weeks L-NAME + 3 weeks placebo), spironolactone-induced reversion (4 weeks L-NAME + 3 weeks spironolactone) and L-arginine-induced reversion (4 weeks L-NAME+ 3 weeks L-arginine). Blood pressure was measured by tail-cuff plethysmography. Relative weight of the LV, myocardial fibrosis (based upon histomorphometry and hydroxyproline determination) and conjugated dienes in the LV and aortic cross-sectional area, inner diameter and wall thickness were determined. NO-synthase activity was investigated in the LV and aorta.

RESULTS

L-NAME administration induced hypertension, left ventricular hypertrophy (LVH), LV fibrosis, aortic thickening and diminution of NO-synthase activity in the LV and aorta. Reduction in blood pressure and regression of LVH were observed in all recovery groups, yet reduction in LV fibrosis and aortic thickening were not. NO-synthase activity was restored only in the L-arginine and spironolactone group.

CONCLUSION

In our study, the reversion of hypertension and LVH was not dependent on the restoration of NO-synthase activity. Moreover, LV fibrosis and aortic remodelling seem to be more resistant to conditions resulting in regression of LVH. Preserved level of fibrosis in the initial period of LVH regression might result in loss of structural homogeneity and possible functional alterations of the LV.

The role of oxidative stress in the pathogenesis of Alzheimer's disease

Oxidative stress has been implicated in the pathogenesis of Alzheimer's disease (AD) as a relevant marker of neuronal degeneration. However it plays an important role not only in the pathogenesis of neurodegenerative diseases but also in other critical disorders like heart diseases, carcinogenesis and others. Oxidative stress is also associated with normal aging. In this review we discuss a crucial question: to what extent oxidative stress may be a causative factor in pathogenesis of AD type of neurodegeneration. The results of several recent epidemiological studies appeared to be controversial at this point. It is believed that antioxidant therapies may have beneficial effects at least in delaying disease progression and appearance of AD specific clinical symptoms. Since there is no cure for AD recently, healthy life style and antioxidants enriched nutrition (or even antioxidant therapy) may provide an effective way of fighting against this deleterious disease (Ref. 102).

Does vagus nerve constitute a self-organization complexity or a "hidden network"?

The vagus nerve provides wide visceromotor and viscerosensory innervation of internal organs. Findings accumulated in last years suggest that vagus nerve participates on regulation of much wider spectrum of functions than described previously. Many different studies provide plausible evidence that vagus nerve importantly participates not only in transmission of information from inflamed tissues, but also in efferent modulation of inflammatory processes. Moreover, there are some findings supporting the hypothesis that vagus nerve might participates in monitoring and modulation of tumorigenesis. Electrical stimulation of the vagus nerve is used as a treatment of epilepsy. Moreover, data also suggest a beneficial effect of electrical stimulation of the vagus nerve in patients with depression, anxiety, migraine and Alzheimer's disease. We suggest, that the vagus nerve might constitute a highly differentiated complex system which modulates various functions. Moreover, we propose that the vagus nerve as a complex system might participate in constitution of a biological compartment of conscious. In this article we discuss findings and ideas supporting these hypotheses (Ref. 73).

Neuroinflammation in Alzheimer's disease: protector or promoter?

Alzheimer's disease (AD) is an irreversible, progressive and degenerative disorder that destroys the higher structures of the brain. Prominent neuropathologic features of AD are senile plaques, neurofibrillary tangles, synaptic and neuronal loss. There is mounting evidence that chronic inflammatory processes play a fundamental role in the progression of neuropathological changes of AD. It has been shown, that there is a reciprocal relationship between the local inflammation and senile plaques (SPs) and neurofibrillary tangles (NFTs). The major players involved in the inflammatory process in AD are thought to be the microglia and the astrocytes. The process of the activation of glia is characteristized by upregulation or newly expression of a variety of molecules involved in inflammatory response including cytokines, various components of the complement cascade, acute phase reactants, proteases and protease inhibitors, and neurotoxic products. The importance of inflammation in the pathogenesis of AD was indirectly confirmed by epidemiological investigations that revealed a decreased incidence of AD in subjects using anti-inflammatory drugs, especially the non-steroidal anti-inflammatory drugs (NSAIDs). However clinical trials designed to inhibit inflammation have failed in the treatment of AD patients suggesting that anti-inflammatory agents have more protective than therapeutic effect. Despite the ongoing research the extent to which neuroinflammation contributes to disease pathogenesis is still not fully understood. Moreover it is also not clear whether the inflammation in AD brains represent a protective reaction to neurodegeneration or it is rather a destructive process that contributes to further loss of brain function. (Ref. 117).

Body surface integral maps in patients with arrhythmogenic right ventricular cardiomyopathy

OBJECTIVES

The aim of this study was to evaluate changes in QRST integral maps in patients with ARVC.

BACKGROUND

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a progressive disorder of predominantly right ventricle characterized with arrhythmic events possibly leading to sudden cardiac death. QRST integral maps reflect local disparities of ventricular repolarization and resulting vulnerability to arrhythmias.

METHODS

A group of 8 patients with ARVC and a control group of 8 patients with a concealed accessory pathway were studied. Body surface mapping was performed using a 63-lead Savard's system.

RESULTS

Mean QRST integral map of patients with ARVC showed abnormal characteristics. The area of negativity was larger than normal and extended to lower border of thorax. Departure map of the mean QRST integral map of patients with ARVC showed areas with departure index < 2 and > 2 in lower part of chest and upper part of back. When statistically analyzed, areas with p < 0.05 covered nearly lower half of chest and upper half of back.

CONCLUSIONS

We consider body surface QRST integral mapping to be an adequate method for evaluation of dispersion of ventricular repolarization in ARVC patients (Tab. 1, Fig. 5, Ref. 17).

Arrhythmogenic right ventricular cardiomyopathy/dysplasia

Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a progressive disease of predominantly right ventricle, characterized by ventricular arrhythmias possible leading to sudden cardiac death. Genetic predisposition was confirmed more than 15 years ago. Autosomal dominant are forms ARVD1-9, Naxos disease (with subtype Carvajal syndrome) is recessive. In ARVC/D forms associated with desmosomal disorders are ventricular arrhythmias caused by the presence of myocardial damage and in forms associated with ryanodine receptor mutation is electrical instability and subsequent myocardial damage caused by calcium cell overload. Main clinical signs are ventricular arrhythmias originated from areas with slow conduction. Progression of ARVC/D is manifested by RV dilatation and LV echocardiographic abnormalities both considered as main risk factors of fatal ventricular arrhythmias and sudden cardiac death. Therapeutic possibilities include antiarrhythmic drugs, catheter ablation and implantation of cardioverter-defibrillator, in severe right or both ventricle involvement even heart failure treatment (Tab. 1, Ref. 56).

Adenosine and cardioprotection: what can we learn from nature's genetic polymorphism?

Adenosine is an endogenous nucleoside that has been shown to be beneficial for the myocardium in different settings by a large number of experimental studies. In this article, we 1) outline adenosine's metabolic pathways, 2) address cardioprotective properties of adenosine, and 3) discuss possible implications of the two recently published clinical studies disclosing a positive effect of adenosine monophosphate deaminase 1 (AMPD1) gene mutation on cardiovascular survival in heart failure and ischemic heart disease. (Fig. 2, Ref. 84.)

Heart remodeling in the hereditary hypertriglyceridemic rat: effect of captopril and nitric oxide deficiency

AIM

The hereditary hypertriglyceridemic (hHTg) rat is characterized by insulin resistance, hypertension, and hypertriglyceridemia. Thus, we investigated whether (a) remodeling of the heart left ventricle (LV) is present under the given hypertensive situation and (b) whether this potential alteration could be influenced by an inhibition of the angiotensin converting enzyme (ACE) and/or by a blockade of nitric oxide production.

METHODS

Five groups of rats were investigated: control Wistar (C) rats, hHTg rats, hHTg rats given captopril (100 mg/kg/day) (hHTg + CAP) or NG-nitro-l-arginine methyl ester (L-NAME, 40 mg/kg/day) (hHTg + L-NAME), and hHTg rats given the combination of both drugs (hHTg + CAP + L-NAME) for 28 days. Systolic blood pressure (SBP) was measured by tail-cuff plethysmography each week. After cervical dislocation, the relative weights of the left and right ventricles (LV/BW, RV/BW) were obtained, the LV nucleic acid concentrations were analyzed, and the fibrosis amount was quantified with aid of a semiquantitative histological technique.

RESULTS

In the hHTg group, the increased SBP (141.7 +/- 4.4 vs. 117.2 +/- 3.1 mmHg in controls) was linked to hypertrophy of the LV (1.63 +/- 0.05 vs. 1.30 +/- 0.03 g/kg in controls) with only a minimum of fibrosis. DNA concentration in the LV was decreased (0.45 +/- 0.03 vs. 0.69 +/- 0.04 mg/g w.w. in controls) in the hHTg group. Captopril normalized SBP and decreased the LV/BW (1.44 +/- 0.04 g/kg). Chronic administration of L-NAME to the hHTg rats additionally enhanced (189.3 +/- 5.9 mmHg) the already raised SBP, stimulated fibrosis development, and increased DNA concentration (0.54 +/- 0.02 mg/g w.w.) in the LV compared to hHTg group, yet without additional weight increase of the LV. The combined treatment of the hHTg rats with CAP and L-NAME resulted in normal SBP and the development of LV hypertrophy, and fibrosis was substantially reduced.

CONCLUSIONS

(a) The heart of hHTg rats carries signs of LV hypertrophy with minimal fibrosis. (b) Nevertheless, LV fibrosis was increased in the hHTg + L-NAME group. (c) Captopril normalized SBP and decreased the extent of LV hypertrophy in both the nontreated hHTg and the hHTg + L-NAME groups and (d) substantially reduced the development of LV fibrosis in the hHTg + L-NAME group. LVH in hHTg rats may be induced by sympathoadrenal system activation, circulating volume enlargement, and impairment of nitric oxide (NO) production rather than by activation of the renin-angiotensin-aldosterone system.

Our experience with surgical treatment of ischial nerve injuries

OUTLINE

This report presents the results of 44 surgical interventions performed on 44 patients during a period of 15 years, from 1985 to 1999. The report presents the basic lines of surgical treatment performed on a total number of 50 peripheral nerves of lower extremities--nervus ischiadicus and its rami.

PATIENT GROUP AND METHODS

In the whole group of 44 patients, external neurolysis was performed in 23 individuals on 26 nerves. Remaining 21 patients were treated by reconstruction surgery that included 24 injured nerves. In this subgroup, suture of peripheral nerve was performed in 8 treatments on 9 nerves and neural graft was performed in 13 treatments of 15 nerves in cases of complete and persisting neurological deficit, and in the absence of action potentials as revealed by EMG. Complete or severe motoric defects and the absence of spontaneous recovery during the period of several months were the indications for the treatment. The analysis of the efficiency of surgical treatment was performed with respect to the following parameters: period between the injury and operation, patient's age, character of injury, type of injured nerve, and type of surgical intervention.

RESULTS

The best results were obtained in external neurolysis which was applied in traumatic lesions of least severity. The effective degree of recovery M3 was observed in 21 patients (91.3%). With respect to reconstruction surgery, more favourable results were obtained in treatments involving suture (in 6 patients, 75%) than in nerve grafts used for the treatment of the most severe injuries associated with a loss of nerve tissue. In the latter cases, improvement was observed after a delay, and the extent of recovery did not always meet the expectations. The effective degree of recovery was observed in 4 patients (30.8%). Good and excellent results were typical for n. tibialis and they were not dependent on the type of surgical intervention, character and location of the injury, period from the injury or patient's age.

CONCLUSION

Our results demonstrate that late and inappropriate treatment of injured peripheral nerves has severe and disturbing consequences for the patient. If a complete treatment of the injured nerve is not possible by the first contact physician, it should be performed as soon as possible by a specialist trained for microneurosurgical techniques of the treatment of peripheral nerves. (Tab. 6, Ref. 11.)

Frequency-domain analysis of the QRS complex after treatment of childhood cancer with anthracycline cytostatics

Long-term cardiac complications, occurring several years after completion of anticancer treatment, may develop from subclinical myocardial damage induced during cardiotoxic therapy. The aim of this study was to evaluate the usefulness of frequency-domain signal-averaged ECG analysis of the QRS complex for assessing the cardiotoxicity of anthracycline cytostatics. Altogether, 172 signal-averaged electrocardiography (SAECG) registrations were performed in 50 repeatedly evaluated oncologic patients. These registrations were performed 0.2-15 years after completion of anthracycline therapy for childhood cancer. The control group consisted of 120 healthy children and young volunteers; in 20 of these controls, SAECGs were performed repeatedly. Using gliding window fast Fourier transformation within the QRS complex, values area ratio (AR) 60-120 Hz/0-120 Hz were calculated in X, Y, and Z lead. Area ratio of patients after anthracycline therapy was significantly higher than those in control group in X lead. Differences in frequency content in the QRS complex between patients and controls might signal an initial stage of anthracycline-induced myocardial damage.

[Frequency analysis of the QRS complex: a new method of detecting development of myocardial damage after anthracycline cytostatics]

The aim of the study was to investigate the effect of the new modification of frequency-domain analysis of ECG signal (gliding-window FFT) in long-term monitoring of cardiac status of patients who received a potentially cardiotoxic anthracycline therapy in childhood. Area ratio (60-120/0-120 Hz) peaks within QRS complex were significantly higher in 60 patients compared with 70 healthy children and young adults. Persistent abnormalities in frequency content of ECG signal in oncologic patients might indicate myocardial damage induced by anthracyclines. (Fig. 1, Ref. 17.)

[Free nerve transplants in the reconstruction of secondary defects of the peripheral nerves of the hand]

BACKGROUND

Peripheral nerve of the hand significantly participate ub the physiological functions of the hand. A defect in the area of the peripheral nerve therefore represents a problem, the solution of which is in the field of microsurgical reconstruction. The study deals with the possibility of microsurgical reconstruction by use of free nerve draft.

SUBJECTIVE

Clinical observation of patients after microsurgical reconstruction of the hand peripheral nerve defect.

MATERIAL AND METHODS

34 patients after lesions of the median nerve, ulnar nerve and mutual impairment of both nerves. The evaluation according the known and spread system system of Medical Research Council, Seddon 1954.

RESULTS

We have achieved very good results after isolated lesions of the median nerve, while the results in this, as well a in other groups are better in younger patients and in patients, in whom the devastation of tissue was not too great. Standard results were achieved in the group with isolated injury of the ulnar nerve and the worst results in a small group of concommitant impairment of both median and ulnar nerves.

CONCLUSIONS

The results indicate that this method is unambiquously appropriate in such a complicated clinical picture. Our results are in accord with the data from other literature sources. MEANING FOR PRACTICE: Inevitability of specialized centres which would deal with this problem thus reducing the necessity of secondary reconstruction operations and naturally the reduction of financial expenditure or social support provision.

Late effects of anthracycline therapy in childhood on signal-averaged ECG parameters

The aim of this study was to investigate the long-term effects of anthracycline cytostatics upon the frequency-domain characteristics of the signal-averaged electrocardiogram (SAECG) and to evaluate the differences in the frequency content according to gender. At mean follow-up period of 4 years 188 SAECGs were repeatedly performed in 62 childhood cancer survivors, who were in complete remission 1-14 years following anthracycline therapy (mean dose 256 mg/m2). No patient had an abnormal end-of-therapy echocardiogram. The control group consisted of 100 healthy children and young adults. 23% patients vs 5% controls had abnormal area ratio (AR) values (over the 97th percentil of normal controls). Abnormalities in AR remained persistent in 15% of cancer survivors. Frequency-domain analysis revealed significantly higher AR 40-100/0-40 Hz in patients after anthracycline therapy than in controls. Within the patient group significantly higher AR were observed in females than in males. Permanent altered frequency components in SAECGs from cancer survivors, evident particularly in female patients, might signal an increased electrical instability in these patients.

Voltage sum of filtered ECG signal--a sensitive parameter of ventricular activation

On the basis of the signal averaged ECG (SA ECG) principle the authors analyse the gradually filtered ECG signal (in ranges of 0-120 Hz with increments of 10 Hz). The voltage sums are determined in eight segments of the QRS complex. The described VSF-ECG method (Voltage Sum of Filtered ECG) was applied in a group of healthy probands and in groups of selected patients. The measurements in healthy probands were used to determine the value of standard in healthy subjects. Repeated measurements confirmed a good reproducibility of the VSF-ECG method. The method enables a precise quantification of heart activation progression. VSF-ECG is a method revealing the changes of heart activation progression being not reflected as late potentials. Parameters of the method are indicators of activation splitting upon the infarction area and also an indicator of the electric milieu of the entire heart.

Signal-averaged ECG in patients with antidepressant therapy

The signal-averaged electrocardiography (SAECG) identifies patients at risk of ventricular arrhythmias and sudden cardiac death. Since the similarity has been known of the pharmacology of class I antiarrhythmics and tricyclic antidepressants, the potential proarrhythmic effects of antidepressants has become a particular problem. The influence of sodium channel blocking antidepressant drugs on the SAECG time-domain parameters was evaluated, using high-pass filters of 25 Hz and 40 Hz. SAECG was performed in 11 depressed patients with normal cardiac status before and for 4 weeks after antidepressant initiation. At the filter setting of 25 Hz, a significant worsening of all studied SAECG parameters (filtered QRS duration, low-amplitude signal duration, root mean square voltage in the first and in the last 40 ms of the filtered QRS) was found in our patient group. Using a 40 Hz high-pass filter, the results were similar. Antidepressant therapy significantly prolonged filtered QRS duration, significantly reduced root mean square voltages in the first and in the last 40 ms of the filtered QRS and non-significantly prolonged low amplitude signal duration. Amitriptyline and maprotiline induced late potentials (LP) in 2 patients at 40 Hz high pass filter setting. No patient had LP at 25-250 Hz. Our pilot study indicates that sodium channel blocking antidepressant drugs may affect SAECG variables similarly to class I antiarrhythmics. SAECG might be useful in categorizing of antidepressant agents and risk stratification of psychiatric patients.

Remodeling in myocardial infarction and body surface potential maps

This study deals with the capabilities of body surface integral and departure maps to evaluate the chronic stage of myocardial infarction based on dividing the left ventricle into 12 segments. The effects of ventricular remodeling on electrocardiographic potential distributions are considered. A 61-year-old male patient was examined five times by body surface potential mapping during a period of 9 months after acute myocardial infarction. Integral maps were calculated for 60 ms after QRS onset and compared with mean data from a control group using departure maps. Integral maps showed a continual reduction of negative potentials in the lower half of the torso with time. The negative area covered the lower torso in the departure maps during the whole study, but its form and value changed. According to the location of the departure area, the surface projection of the scar moved from a position corresponding to inferior segments to a position corresponding to posterior segments. Its size also decreased. Echocardiographic examinations showed progressive enlargement of both ventricles with time. Therefore, the authors postulate that the changing pattern of body surface potential maps was mainly influenced by ventricular remodeling after myocardial infarction.

Gliding window fast Fourier transform analysis--a new method for discovering the contribution of higher frequencies in signal-averaged ECG

OBJECTIVE

An attempt to detect the 'parasitic contribution' of high frequencies in the electrocardiogram signal.

DESIGN

A new method--gliding window fast Fourier transform analysis (GWFFTA)--was developed. It was applied in healthy subjects and in patients with acute myocardial infarction.

SETTING

Faculty of Medicine and University Hospital.

PATIENTS

The GWFFTA was used in 29 healthy volunteers and in a group of 30 patients with myocardial infarction, on day 7 to 14 after admission to a coronary unit.

INTERVENTION

Noninvasive examination, performed under standard conditions.

MAIN RESULTS

GWFFTA provides better reproducible results compared with 'classic' fast Fourier transform analysis. The parasitic contribution of high frequencies within QRS complex and ST segment in patients with acute myocardial infarction is independent of presence or absence of late potentials. Contribution of high frequencies are three times higher in patients with acute myocardial infarction than in healthy probands.

CONCLUSIONS

GWFFTA is a reproducible method of detection of high frequencies during whole heart activation. Contribution of high frequencies in patients with acute myocardial infarction reflects the state of the entire myocardium. It is also confirmed by the lack of correlation with the presence or absence of late potentials. Late potentials are more reflective of focal changes.

Computer graphics and computer animation of the electric heart field

The authors present in their paper the possibilities of the application of computer graphics and computer animation for visualization of the electric heart field (EHF). They describe the construction of three-dimensional potential maps by the methods of interpolation, perspective projection, hidden line elimination and text generation. They also present a method for making of animation films showing the electric activity of the heart by using 80 three-dimensional potential maps recorded at different intervals over the entire cardiac cycle.