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Jacek Gajek

Publications and source records attributed to Jacek Gajek.

18 recordsLinked to original sources

Influence of tilt training on activation of the autonomic nervous system in patients with vasovagal syncope.

OBJECTIVE: Tilt training is a new treatment for vasovagal syncope. Its therapeutic efficacy is thought to be the result of the desensitization of cardiopulmonary receptors, but it could be the influence of the tilt training on the activation of the autonomic nervous system as well. METHODS AND RESULTS: The study group consisted of 24 vasovagal patients (17 women and 7 men) aged 32.5 +/- 11.8 years. The diagnostic head-up tilt test was performed according to the Italian protocol with nitroglycerin if necessary. The monitoring head-up tilt test was performed according to the Westminster protocol without provocation, after 1 to 3 months of tilt training. Holter ECG recordings for HRV parameters (time and frequency domain) were obtained from selected 2-min intervals before, during and after the diagnostic and monitoring tilt test. The diagnostic test was positive in the passive phase in 6 and after provocation in 18 patients. During the training period no syncope occurred. Analysing the HRV parameters we demonstrated the following findings: I. mRR decreases immediately after assumption of a vertical position in both tests (diagnostic and monitoring) but in the diagnostic test its further decrease occurs earlier than in the monitoring test; 2. the absolute power of the HF component is greater in the early phase of tilt after tilt training than in the corresponding period in the diagnostic test. CONCLUSIONS: After a longer period of tilt training the activation of the sympathetic nervous system in response to the erect position is diminished.

Adolescent↗

Efficacy of tilt training in patients with vasovagal syncope.

BACKGROUND: Besides pharmacological therapy and pacemaker implantation, tilt training is a promising method of treatment in patients with vasovagal syncope (VVS). Tilt training is usually offered to patients with malignant or recurrent VVS which impairs their quality of life and carries a risk of injury. AIM: To assess the efficacy of tilt training in patients with VVS. METHODS: The study group consisted of 40 patients (29 females, 11 males, aged 36.6+/-14 years, range 18-57 years) who underwent tilt training using tilt table testing according to the Westminster protocol. The mean number of syncopal episodes prior to the initiation of tilt training was 6.5+/-4.9 (range 0-20); 3 patients had a history of very frequent faints. According to the VASIS classification, type I VVS (mixed) was diagnosed in 17 patients, type II (cardioinhibitory) in 22 subjects, and type III (vasodepressive) in one patient. Mean follow-up duration was 35.1+/-13.5 months. The control group, which did not undergo the tilt testing programme, consisted of 29 patients with VVS (25 females, 4 males, mean age 44.2+/-15.0 years) who had a mean of 3.3+/-3.2 (range 0-12) syncopal episodes in the past (p <0.05 vs study group); 6 of these patients had only pre-syncopal episodes. Type I VVS was diagnosed in 23 controls and type II VVS in 6 control subjects (syncope occurred during the passive phase of tilt testing in 7 subjects, whereas the remaining 22 fainted during NTG infusion). RESULTS: Of the patients from the study group, 3 underwent pacemaker implantation at the time of the initiation of tilt training. At the end of follow-up, 31 (77.5%) patients remained free from syncope recurrences, 5 had syncopal episodes during the initial phase of tilt training, whereas the remaining 4 continued to suffer from syncopal episodes. Out of 3 patients with presyncope, 2 had no syncope recurrences whereas 1 patient continued to have presyncopal attacks. Out of 3 patients with pacemakers, 1 reported activation of pacing in the interventional mode. During the follow-up period, in 5 patients from the study group the diagnosis of VVS was not confirmed and another condition was diagnosed. In the control group, syncope recurrences occurred in 13 (44.5%) patients (p <0.05 vs study group). CONCLUSIONS: In patients with VVS, tilt training is effective in the majority of patients. Syncopal or presyncopal episodes and positive results of tilt testing take place more frequently in the early rather than in the late phase of training. Cessation of tilt training causes a recurrence of positive results of tilt testing in spite of the lack of spontaneous syncopal episodes. During long-term observation, a proper diagnosis, different from VVS, can be established in some patients.

Adult↗

[Renin-angiotensin-aldosterone system activity during head-up tilt testing in patients with vasovagal syncope].

UNLABELLED: The stimulation of renin-angiotensin-aldosterone (RAA) system during tilt table test is caused by sympathetic nervous system activation by orthostatic stress and a serotonin release as well. In healthy individuals increase of plasma renin activity during test with maximal values on the peak of the test was described. OBJECTIVE: The aim of the study was to assess the activation of RAAS in patients with neurally mediated syncope during the tilt table test by means of plasma renin activity and serum aldosterone levels. MATERIAL AND METHODS: The study was carried out in 31 patients aged 39.4 +/- 15.0 years (18 women and 13 men) with neurally mediated syncope during tilt test. Plasma renin activity was assessed in the baseline conditions, immediately after the test and 10 minutes after the test using radioenzymatic assay. Aldosterone concentrations were measured radioimmunologically, twice: after 30 minutes supine rest and after the syncope. RESULTS: Plasma renin activity during supine rest was 2.2 +/- 2.4 ng/ml/h, rose after the syncope 2.5-fold to 5.2 +/- 4.5 ng/ml/h (p < 0.001 comparing to baseline) stayed on similar level approximately for the next 10 minutes--4.9 +/- 5.5 ng/ml/h (p = n.s.). In 11 patients (35%) 10 minutes after the test even further increase of PRA was observed. Serum aldosterone level increased significantly immediately after tilt test (90.0 +/- 72.9 vs 178.8 +/- 150.1 pg/ml, p < 0.01). CONCLUSION: Authors showed, that in patients with NMS plasma renin activity increases and this increase lasts for 10 minutes after the syncope and the concentration of aldosterone increases immediately after tilt test.

Adult↗

Heart rate variability in workers chronically exposed to lead.

BACKGROUND: Lead is a strong neurotoxin. The effects of lead on the activity of the autonomic nervous system, assessed by the use of heart rate variability (HRV) analysis, have not yet been established. AIM: To assess the effects of occupational chronic lead exposure on the autonomic nervous system activity. METHODS: The study group consisted of 22 copper foundry workers (mean age 41.8+/-8.7 years) who had elevated parameters of lead overload and were admitted to the hospital for chelate therapy. The control group consisted of 13 age-matched healthy males. Lead concentration was measured with the use of atomic absorption spectrophotometry, and concentration of free protoporphyrins in erythrocytes (FEP) using a fluorometric method. Each patient underwent 24-hour ambulatory ECG monitoring, and standard short-term as well as long-term HRV parameters were obtained. RESULTS: There were no significant differences between patients and controls in HRV parameters. In the control group, HRV parameters correlated with age. In patients, a significant negative correlation between lead concentration and some short-term HRV parameters calculated during the night was found: SDNN (r=-0.48, p<0.05), TP (r=-0.48, p<0.01) and LF (r=-0.48, p<0.01). In patients, a negative correlation between lead concentration and HFnight/HFday index was found (r=-0.47 p<0.01), whereas in controls this correlation was positive (r=0.66 p<0.05). CONCLUSIONS: Overall HRV indices are similar in subjects exposed to lead and in healthy controls. A decrease in the physiological elevation of HF values during the night, together with an increase in lead blood concentration and lack of relationship between age and HRV parameters in workers chronically exposed to lead may suggest disturbances of the autonomic system. In subjects not exposed to lead a decrease in heart rate with an increase in FEP concentration was observed.

Adult↗

[Thyroid and cardiovascular disorders].

In this study three problems concerning interactions between thyroid and cardiovascular system are discussed. Cardiac arrhythmias, congestive heart failure, pleural effusion, hyperlipidaemia, arterial hypertension may be consequences of thyroid disorders leading to inappropriate hormone secretion. During such illnesses as heart failure, myocardial infarction and in patients undergoing coronary artery bypass surgery profound changes may occur in thyroid hormone metabolism known as sick euthyroid syndrome. Treatment with amiodarone may lead to changes in thyroid tests results and to development of hypothyroidism or thyrotoxicosis.

Amiodarone↗

Activation of generalised inflammatory reaction following electrical cardioversion.

BACKGROUND: Restoration of sinus rhythm in patients with atrial fibrillation (AF) is associated with an increased risk of thrombo-embolic complications due to delayed return of the left atrial and left atrial appendage systolic function. Direct current cardioversion (DC), used for AF termination, may cause myocardial injury and subsequent activation of inflammatory response. A C-reactive protein (CRP) is a non-specific marker of inflammation. AIM: To examine the effects of external DC of AF or atrial flutter (AFlut) on inflammatory processes. METHODS: The study group consisted of 35 patients (20 females and 15 males, mean age 67.9+/-9.7 years, range 46-83 years) with paroxysmal or persistent AF/AFlut who underwent elective DC. CRP plasma concentration was measured before and 24 hours after DC. RESULTS: The mean total DC energy was 431.2 J. CRP plasma concentration increased significantly following DC - from 3.9+/-3.4 ng/ml before DC to 7.2+/-6.7 ng/ml after DC (p<0.0001). CRP level correlated with body mass index (r=0.34, p<0.05), however, this correlation became non-significant after inclusion of the presence of diabetes into the statistical model. There was also a positive correlation between CRP values before and after DC (r=0.72, p<0.0001). No correlation between CRP and gender, total power of DC nor the number of DC shocks was detected. CONCLUSIONS: External DC of AF/Aflut causes activation of inflammatory processes measured as a significant increase in the CRP plasma concentration.

Aged↗

[Adrenomedullin--the link between the sympathetic nervous system activation and peripheral vasodilatation in some patients with vasovagal syncope].

UNLABELLED: Adrenomedullin (ADM) is a potent vasodilator playing role in regulation of central hemodynamic. The concentration of plasma ADM in healthy people increases under the influence of orthostatic stress. In patients with vasovagal syncope (VS) the changes in ADM concentration could be responsible either for syncope provocation or prevention. The aim of the study was to assess the influence of phase of the head-up tilt test (HUTT) in which the syncope occurred on the plasma concentration of ADM. MATERIAL AND METHODS: The study was performed in 25 patients (pts) (18 women and 7 men), mean age 45.0+/-16.1 years with cardiodepressive reactions during HUTT according to the Italian protocol with nitroglycerine (NTG) provocation if necessary: Syncope was caused in 23 pts due to vasovagal reaction: in 17 pts syncope occurred after NTG provocation (group 1), and in 6 pts occurred in the passive phase of tilt (group 2a), in 2 pts due to dysautonomic reactions (group 2b). The head-up tilt test was performed according to ESC guidelines. The blood for ADM concentration was drawn after 30 min supine rest (ADM 1) and immediately after syncope (ADM 2). ADM level was measured using radioimmunological method. The results. In group 1 plasma level of ADM significantly decreased after the HUTT (3.2+/-3.4 vs 1.7+/-1,4 pg/0.1 ml; p<0.05) and in group 2a increased significantly (1.3+/-0.8 vs 2.7+/-1.3 pg/0.1 ml; p<0.05) comparing to baseline values. The ADM concentration did not differ between the groups in baseline conditions and was significantly higher after the syncope in group 2a (p<0.05). Conclusions. The excessive increase of ADM concentration during the passive phase of HUTT could play the causative role in pathogenesis of VS occurring early during the HUTT. In patients with VS after NTG provocation the decrease of ADM concentration can be the result of hemodynamic changes in the presence of vasodilating drug and may be the mechanism that could prevent the syncope.

Adrenomedullin↗

[Therapeutic approach to patients with neurocardiogenic syncope].

Vasovagal syncopes are the most common cause of loss of consciousness and if they occur frequently they contribute to the marked decrease of the quality of life and need treatment. One of important problems is the possibility of injury during the syncope. In older patients it can lead to the fractures of extremities, complications of which could be life-threatening. Another problem is the reaction of the surrounding people trying to help the unconscious by keeping him in the vertical position. It promotes hypotonia and could cause damage of organs such as brain or heart. The authors review the current literature on the management of patients with vasovagal syncope. It seems that the conservative approaches preferring patient reassurance and training methods are successful in syncope prevention and help avoid the side effects and complications of pharmacological therapy or pacemaker implantation. These last two methods should be reserved for patients with the most severe symptoms of the disease.

Humans↗

[Effect of lead on the cardiovascular system].

Lead is a metal widely spread in the natural environment. It is strongly toxic, particularly to the peripheral and central nervous systems. The toxic influence on the cardiovascular system is most pronounced in case of higher exposures, where myocardium and the renal circulation are affected, in consequence of which secondary arterial hypertension can develop. It seems that lead affects the cardiovascular system mainly by changing the peripheral autonomic nervous system and leading to chronic neuropathy. Chronic exposure, even to low doses of lead, can impair conduction in myocardium. In order to assess those changes thoroughly prospective studies involving newly employed workers with occupational exposure to toxic activity of lead will be necessary.

Autonomic Nervous System↗

[Neurohumoral mechanisms for vasovagal syncopes. Part I].

Vasovagal syncope is defined as a reflex loss of consciousness related to reaction to various stimuli as orthostatic stress, pain or emotions connected with loss of muscle postural tone. The aetiology of this disorder is still unknown. The imbalance between the parts of autonomic nervous system and other homeostasis-related systems as renin-angiotensin-aldosterone system, peptides as endothelin, neuropeptide Y, vasopressin, adrenomedullin and cAMP, adenosine and AMP can play an important role in the development of vasovagal syncope. In the first part of the paper the authors describe the mechanisms involved in the development of vasovagal reaction, pathophysiology of the head-up tilt test and the role of autonomic nervous system.

Adrenomedullin↗

[Neurohumoral mechanisms for vasovagal syncopes. Part II].

Vasovagal syncope is defined as a reflex loss of consciousness related to reaction to various stimuli as orthostatic stress, pain or emotions connected with loss of muscle postural tone. In the second part of the paper the authors describe the possible role of the particular neurohumoral factors and autonomic nervous system in the development of vasovagal syncope. The studies on the involvement of neurohumoral factors in vasovagal syncope can play a key role in a more precise evaluation of affected patients, long term prophylaxis against syncopal events and may contribute to development of more reliable diagnostic tests.

Adrenomedullin↗

[The influence of physical exercise on heart rate variability].

Heart rate variability is controlled by the influence of autonomic nervous system, whereas one part of the system modulates the activity of the other. There is evidence of increased sympathetic activity in patients (pts) with essential hypertension. The aim of the study was to assess the persisting influence of increased sympathetic activity 30 min after moderate physical exercise on heart rate variability in patients with arterial hypertension. The study was performed in 19 patients (10 women, mean age 52.7 +/- 9.5 years and 9 men, mean age 37.7 +/- 8.8 years) with stage I (6 pts) and stage II (13 pts) arterial hypertension. All studied pts had sinus rhythm, were free of diabetes, coronary heart disease and congestive heart failure. 24-hour Holter monitoring was performed and for 30 min before the exercise test the pts stayed in supine rest. The exercise tests were performed between 10 and 11 a.m. Immediately after the exercise all pts stayed in supine position for 30 min. The heart rate variability parameters were studied using Holter monitoring system Medilog Optima Jet and were then analysed statistically. The mean energy expenditure during the exercise was 5.8 +/- 1.1 METs and the maximal heart rate was 148.1 +/- 20.3 bpm. All studied HRV parameters were significantly different in the assessed time period compared to the baseline values (p < 0.001). Significant correlation was found between the age of the studied patients and the mean RR interval, what can be considered as a hyperkinetic (hyperadrenergic) circulatory status and shorter RR interval in younger pts. Significant negative correlation between the age and SDNN parameter (r = -0.65, p < 0.001), 30 min after the exercise mirrors the prolonged adrenergic influence in older pts. The present study shows that the influence of moderate physical exercise on heart rate variability in pts with essential hypertension is extended over 30 min period after exercise and is more pronounced in older pts. The studies on HRV should be performed at longer time intervals after exercise.

Adult↗

[Controversies in the conduction and evaluation of clinical trials results for the treatment in vasovagal syncope].

The vasovagal syncope is a reflex reaction to various stimuli leading to the marked hypotension with or without bradycardia with loss of consciousness and fall of postural muscle tone. The vast majority of the patients recover spontaneously but if the syncope occurs frequently and causes injury of the patients body it worsens the quality of life and needs appropriate treatment. The injuries requiring hospitalization occur approximately in 10% of the patients with vasovagal syncope. The aim of the therapy of affected patients is to diminish the syncope prevalence, to brake the neurocardiogenic reaction on an early stage or to prolong the duration of the presyncope phase to enable the patient prevention of the injury. The lack of clear diagnostic criteria and difficulties with estimation the efficacy of any particular therapeutic intervention in many clinical studies of different authors, inclusion to the studies patients with different clinical presentation stages of the disease contribute to different conclusions, which automatic use in the clinical practice is inappropriate. There is an urgent need to clear the methodological discrepancies and to conduct good planed, large, randomized, multicentre studies to assess the efficacy of different therapeutic methods in the treatment of vasovagal syncope.

Evaluation Studies as Topic↗

[Vasovagal syncope as a cause of serious body injury - two case reports].

Vasovagal syncope is a reflex reaction, leading to marked hypotension and/or bradycardia with transient loss of consciousness and the postural muscle tone. The recovery is spontaneous and usually rapid. Serious body injuries caused by fainting are rare. We present two patients with vasovagal syncope which caused serious injury. Different therapeutic options, including pacemaker implantation, are discussed.

Adult↗

[The influence of Chlamydia pneumoniae infection on acute coronary syndromes].

UNLABELLED: Chlamydia pneumoniae is one of the infectious factors the role of which is considered in the process of atherosclerosis and its complications. THE AIM: Of the study was to assess the incidence of Ch. pneumoniae infection in the patients with acute coronary events. The study was carried out in 36 patients, mean age 61.2 +/- 13.4 years, 27 men and 9 women hospitalised in our Department with the diagnosis of previous or recent acute myocardial infarction. The control group consisted of 19 subjects, aged 61.1 +/- 14.3 years, 10 men and 9 women hospitalised due to other reasons. In all studied patients during the first 24 hours venous blood was taken for the assessment of fibrinogen and C-reactive protein (CRP) concentrations and titres of IgA and IgG anti-Ch. pneumoniae antibodies, and pharyngeal swabs were done for Ch. pneumoniae assessment. RESULTS: Positive swab tests were found in 19% of the patients, positive IgG titres in 80% and IgA in 64% of the patients. In the control group the corresponding values were 11, 79, 42%, respectively. In the patients with positive IgG titres, negative IgA titre result was observed in 21% and in the control group in 53% (p < 0.05). The CRP level was significantly higher in the studied patients than in the control group (24.2 vs 4.2 mg/l; p < 0.05). CONCLUSIONS: 1. The high percentage of positive serologic tests and rare positive results of pharyngeal swabs indicate a frequent contact with Ch. pneumoniae in human population. 2. Ch. pneumoniae infection exerts no significant influence on the unspecific markers of inflammation. 3. The higher frequency of seroconversion-positive IgG and negative IgA titres--in the control group indicates the role of prolonged or acute Ch. pneumoniae infection in the development or progression of coronary atherosclerosis and its complications.

Acute Disease↗

[The influence of single moderate exercise on the sympathetic nervous system activity in patients with essential hypertension].

Sympathetic nervous system may play an important role in development and maintenance of hypertension. Its activity can be assessed by plasma levels of catecholamines, neuropeptide Y (NPY) and adrenergic receptor density. Hypertensive subjects may be more prone to reveal overactivity of sympathetic nervous system, for instance as a result of physical stress. The aim of the study was to determine the activity of sympathetic nervous system in young patients with newly recognized, untreated mild hypertension. INVESTIGATED GROUPS AND METHODS: The study was carried out in 22 patients (age 38.5 +/- 10.3 years) and 20 normotensive volunteers (age 38.5 +/- 8.6 years) as a control group, matched for sex. Density of alpha 2- and beta-adrenergic receptors using 3H-yohimbine and 125I-cyanopindolol respectively, total catecholamines and plasma renin activity using radioenzymatic assay, neuropeptide Y and aldosterone using radioimmunoassay were assessed in the blood taken in the supine position and after moderate bicycle ergometer exercise. RESULTS: Plasma concentration of NPY at rest did not differ between the groups, but increased significantly after exercise and was greater in hypertensive patients (p < 0.05). The density of alpha 2- and beta-adrenergic receptors at rest and after exercise in hypertensive subjects was unchanged when comparing to healthy individuals. The plasma concentrations of endogenous catecholamines, plasma renin activity and aldosterone level increase during exercise in both studied groups (p < 0.05). Aldosterone level was higher in hypertensive patients at rest (p < 0.05). There was a negative correlation between baseline aldosterone and NPY levels in hypertensive patients (r = -0.44, p < 0.05). CONCLUSION: Moderate exercise in hypertensive subjects causes the hyperactivity of sympathetic nervous system expressed as increase of NPY plasma level.

Adult↗