Transvenous phrenic nerve stimulation for the treatment of central sleep apnoea in heart failure.

AIMS: Periodic breathing with central sleep apnoea (CSA) is common in heart failure patients and is associated with poor quality of life and increased risk of morbidity and mortality. We conducted a prospective, non-randomized, acute study to determine the feasibility of using unilateral transvenous phrenic nerve stimulation for the treatment of CSA in heart failure patients. METHODS AND RESULTS: Thirty-one patients from six centres underwent attempted transvenous lead placement. Of these, 16 qualified to undergo two successive nights of polysomnography-one night with and one night without phrenic nerve stimulation. Comparisons were made between the two nights using the following indices: apnoea-hypopnoea index (AHI), central apnoea index (CAI), obstructive apnoea index (OAI), hypopnoea index, arousal index, and 4% oxygen desaturation index (ODI4%). Patients underwent phrenic nerve stimulation from either the right brachiocephalic vein (n = 8) or the left brachiocephalic or pericardiophrenic vein (n = 8). Therapy period was (mean ± SD) 251 ± 71 min. Stimulation resulted in significant improvement in the AHI [median (inter-quartile range); 45 (39-59) vs. 23 (12-27) events/h, P = 0.002], CAI [27 (11-38) vs. 1 (0-5) events/h, P≤ 0.001], arousal index [32 (20-42) vs. 12 (9-27) events/h, P = 0.001], and ODI4% [31 (22-36) vs. 14 (7-20) events/h, P = 0.002]. No significant changes occurred in the OAI or hypopnoea index. Two adverse events occurred (lead thrombus and episode of ventricular tachycardia), though neither was directly related to phrenic nerve stimulation therapy. CONCLUSION: Unilateral transvenous phrenic nerve stimulation significantly reduces episodes of CSA and restores a more natural breathing pattern in patients with heart failure. This approach may represent a novel therapy for CSA and warrants further study.

Cardiomyopathy Associated with Right Ventricular Apical Pacing-Systematic Review and Meta-Analysis.

AIMS: Bradyarrhythmias are potentially life-threatening medical conditions. The most widespread treatment for slow rhythms is artificial ventricular pacing. From the inception of the idea of artificial pacing, ventricular leads were located in the apex of the right ventricle. Right ventricular apical pacing (RVAP) was thought to have a deteriorating effect on left ventricular systolic function. The aim of this study was to systematically assess results of randomized controlled trials to determine the effects of right ventricular apical pacing on left ventricular ejection fraction (LVEF). METHODS: we systematically searched the Cochrane Central Register of Controlled Trials, PubMed, and EMBASE databases for studies evaluating the influence of RVAP on LVEF. Pooled mean difference (MD) with a 95% confidence interval (CI) was estimated using a random effect model. RESULTS: 14 randomized controlled trials (RCTs) comprising 885 patients were included. In our meta-analysis, RVAP was associated with statistically significant left ventricular systolic function impairment as measured by LVEF. The mean difference between LVEF at baseline and after intervention amounted to 3.35% (95% CI: 1.80-4.91). CONCLUSION: our meta-analysis confirms that right ventricular apical pacing is associated with progressive deterioration of left ventricular systolic function.

Prospective echocardiographic evaluation of patients with endogenous subclinical hyperthyroidism and after restoring euthyroidism.

OBJECTIVES: Clinical significance of, and the need for, treatment in subclinical hyperthyroidism (sHT) is still a matter of debate. The aim of the study was to assess the impact of sHT on echocardiographic parameters. DESIGN: Patients with endogenous sHT of nonautoimmune origin underwent full echocardiographic assessment at diagnosis and after restoring euthyroidism with radioiodine treatment. PATIENTS: Studied group consisted of 44 patients (37 women, 7 men), aged 22-65 years (mean 45·9±11·0). MEASUREMENTS: Full echocardiographic assessment included estimation of cardiac chamber diameters and volume as well as cardiac contractility, according to the guidelines of the American Society of Echocardiography. Left ventricular mass was calculated according to Penn's convention. For estimation of left ventricle diastolic function, the following echocardiographic parameters were obtained: maximal early filling wave velocity (E), maximal late filling wave velocity (A), E/A ratio, isovolumetric relaxation time and early filling wave deceleration time. RESULTS: In the studied group, phase of sHT was associated with increased volume of heart chambers, increased diameter of ascending aorta, increased left ventricle mass and disturbed left ventricle relaxation (P<0·05). The systolic function of the left ventricle was unaffected; however, the ejection time was shortened. The changes were reversible with restoring biochemical euthyroidism (P<0·05). Moreover, a significant correlation between some of the parameters and thyroid hormones concentration was demonstrated. CONCLUSIONS: sHT was associated with significant changes in echocardiographic parameters, which may contribute to increased cardiovascular risk in these patients. The alterations were reversible with restoring biochemical euthyroidism, what supports the necessity of treatment introduction in sHT.

[Inappropriate therapy of an implantable cardioverter-defibrillator--is it always an undesired event? A case report]. / Nieuzasadnione wyladowanie wszczepialnego kardiowertera-defibrylatora--dzialanie niepozadane czy pozadane?

Inappropriate implantable cardioverter defibrillator (ICD) therapy is the commonest adverse event in patients with ICD. We present a case of sinus rhythm restoration after an inappropriate shock in a man with permanent atrial fibrillation and dilated cardiomyopathy. During follow-up, clinical improvement has been observed.

[Beating myocardial cross sections and polar maps techniques in assessment of myocardial perfusion disturbances with gated single photon emission tomography]. / Analiza ruchomych przekrojów i map biegunowych w ocenie zaburzen perfuzji serca za pomoca bramkowanej tomografii emisyjnej pojedynczego fotonu.

UNLABELLED: In modern world the risk of circulatory system diseases is increasing. Effective techniques are sought of prevention and detection of coronary artery disease. The development of diagnostic modalites is directed to reduction of invasiveness and risk for patients with providing as much information from a single examination, as possible. Gated scintigraphy examinations by single photon emission method (GSPET) seem to meet these requirements. They combine information that could be obtained as yet only with two separated examinations. They provide data on left ventricular perfusion and function. AIM OF THE STUDY: The aim of the study was application of gated single photon emission tomography (GSPET) technique by means of polar maps and beating cross-sections in the assessment of parameters describing left ventricular function in various degrees of myocardial perfusion disturbances. A comparison was also done of GSPET processing by polar map and beating cross-section methods in the diagnosis of perfusion disturbances. MATERIAL AND METHODS: The study group included 142 patients (mean age 55.8 +/- 10.9 years), in whom myocardial scintigraphic examination was carried out by GSPET method using Tc99m-MIBI complex according to two-day protocol. The examinations were performed using a two-head Varicam gamma camera. For study data processing Xpert Pro software for workstation was used. The examinations were analysed using both polar maps and beating cross-sections. Additional values were considered offered by gated GSPET examinations. In all, 284 examinations were analysed. The patients were divided into groups according to gender and changes in perfusion both in the maps and cross-sections. RESULTS: The total number of 112 consistent results of perfusion changes were obtained both in the polar maps and cross-sections (71%). Most differences were observed in the group with effort perfusion disturbances. During processing of GSPET examination by the method of polar maps were obtained more reversible perfusion disturbances then in the beating cross-sections, differences were found which required further studies and comparison with clinical data. CONCLUSIONS: On the basis of the obtained results the conclusions were drawn that processing of gated single photon emission tomography (GSPET) by methods of both polar maps and mobile cross-sections makes possible to assess the parameters describing left ventricular function at rest and during exercise in various degrees of myocardial perfusion disturbances.

Implantable cardioverter-defibrillators in patients with long QT syndrome: a multicentre study.

BACKGROUND: Implantable cardioverter-defibrillator (ICD) therapy has been proven effective in the prevention of sudden cardiac death, but data on outcomes of ICD therapy in the young and otherwise healthy patients with long QT syndrome (LQTS) are limited. AIM: We sought to collect data on appropriate and inappropriate ICD discharges, risk factors, and ICD-related complications. METHODS: All LQTS patients implanted with an ICD in 14 centres were investigated. Demographic, clinical, and ICD therapy data were collected. RESULTS: The study included 67 patients (88% female). Median age at ICD implantation was 31 years (12-77 years). ICD indication was based on resuscitated cardiac arrest in 46 patients, syncope in 18 patients, and malignant family history in three patients. During a median follow-up of 48 months, 39 (58%) patients received one or more ICD therapies. Time to first appropriate discharge was up to 55 months. Inappropriate therapies were triggered by fast sinus rhythm, atrial fibrillation, and T-wave oversensing. No predictors of inappropriate shocks were identified. Risk factors for appropriate ICD therapy were: (1) recurrent syncope despite b-blocker treatment before ICD implantation, (2) pacemaker therapy before ICD implantation, (3) single-chamber ICD, and (4) noncompliance to b-blockers. In 38 (57%) patients, at least one complication occurred. CONCLUSIONS: ICD therapy is effective in nearly half the patient population; however, the rates of early and late complica-tions are high. Although the number of unnecessary ICD shocks and reimplantation procedures may be lowered by modern programming and increased longevity of newer ICD generators, other adverse events are less likely to be reduced.

[Cardiac arrest with subsequent permanent anoxaemic brain damage in a patient with the Brugada syndrome]. / Nagle zatrzymanie krazenia z nastepczym anoksemicznym uszkodzeniem mózgu u pacjenta z zespolem Brugadów.

The paper presents a case of a 20-year-old student with a history of cardiac arrest due to ventricular fibrillation. The episode of cardiac arrest occurred when the patient did not complain of any health problems, and there was no visible structural heart disease. Consequently, permanent anoxaemic brain damage was observed. Based on ECG examination, the Brugada syndrome was diagnosed as the cause of cardiac arrest. The ajmaline challenge test was performed in the members of the patient's family.

[Drugs affecting thyroid--part II]. / Leki wplywajace na czynnosc tarczycy - cz. II.

The use of several groups of medications may result in thyroid dysfunction. So far the best known medication is amiodarone. The role of other medications and diagnostic agents in causing thyroid dysfunction is quite often forgotten. We presented medications and diagnostic agents commonly used in medical day-to-day practice. We described other than amiodarone iodinated agents and quoted recently published European guidelines in using iodinate contrast agents. We focused on lithium and psychiatric drugs and mechanism of their toxic impact on thyroid gland. These agents are important as they are applied for years (including children). At the end the impact of cytokines on thyroid gland was discussed, medications ever more widely applied in anti-viral and anti-neoplastic therapy.

[The effects of amiodaron on the thyroid function]. / Wplyw amiodaronu na czynnosc tarczycy.

The use of several groups of medications may result in thyroid dysfunction including thyrotoxicosis or hypothyroidism of various degree (from subclinical to full-clinical syndrome). The mentioned disturbances may develop either on the basis of normal euthyroid gland or may overlap the previously-existing oceult changes (first of all different forms of autoimmune thyroiditis). Amiodarone is a widely used anti-arrythmic drug with considerable potential to cause thyroid dysfunction because of its 35% iodine content. Besides amiodarone particles are known to inhibit T4 to T3 conversion, they work as inhibitors of nuclear receptors for thyroid hormones, exert cytotoxic effect and induce immune/inflammatory process in thyroid gland. Both thyrotoxicosis (AIT - amiodarone induced thyrotoxicosis) and hypothyroidism (AIH - amiodarone induce hypothyroidism) may develop during amiodarone therapy. AIT appears to occur more frequently in geographical areas with low iodine intake, whereas AIH is more frequent in iodine-sufficient areas. Two forms of AIT are known. Their differentiation is very important for further therapeutical procedures. Because thyrotoxicosis and hypothyroidism symptoms during amiodarone therapy are scanty, there is need for periodic determination of thyroid function. Normal ranges for amiodarone patients differ from those for the rest of population. They are presented in this review. Treatment of AIT is very complicated. Sometimes there is need to use few methods together, especially when amiodarone treatment can not be stopped.

[Positive microvolt T-wave alternans as a marker of ventricular arrhythmia trigering during cardioverter-defibrillator implantation]. / Dodatni wynik badania mikrowoltowej naprzemiennosci zalamka T identyfikujacy chorych podatnych na wywolanie arytmii komorowej podczas wszczepiania kardiowertera-defibrylatora.

Microvolt T-wave alternans (MTWA) is promising method for noninvasive assessment of arrhythmic risk, but its role hasn't established yet. The aim of this study was to establish the MTWA potency to predict the ventricular arrhythmia triggering during implantable cordioverter-defibrillator (ICD) implantation. Material and metods. The study group consisted of 21 patients, aged 63.0+/-8.0 years; EF was 38.0+/-12.8%. Seventeen of them had a history of myocardial infarction and 4 had non-ischemic cardiomyopathy. The reason for ICD implantation were secondary prevention due to nonfatal cardiac arrest caused by VF/VT in nineteen patients and in two patients ICD was implanted because of unexplained syncope and low EF (< or =35%). All patients underwent VT/VF triggering during device implantation caused by electrophysiological study (EPS). If this proved ineffective aggressive protocol of 50 Hz BURST and T SHOCK was applied. After ICD implantation the following tests were performed: ECG with HR, QRS and QTc evaluation, 24-hour ECG Holter monitoring with HRV assessment and MTWA evaluation during treadmill exercise test. Results. In the group with VT/VF induced by less aggressive protocol (EPS), group I (n = 10) MTWA was present in nine patients, in one the result of MTWA was indeterminate. In the group with VT/VF induced by more aggressive protocol, group II (n = 11) MTWA was present in four patients, indeterminate in four and absent in three. There was a significant (p = 0.017) difference between group I and II in the frequency of positive result of MTWA. There were no differences between the two groups according to time domain parameters of HRV such as SDNN, RMSSD and PNN50 and QTc. There was a significant difference between the two groups in time duration of QRS complexes, 118.9+/-14.7 vs. 105.6+/-11.5 accordingly (p < 0.04). Conclusions. MTWA may help identify patients in whom VTNVF is more easily inducible by electrophysiologic study during ICD implantation. It is easier to induce ventricular arrhythmia when QRS complexes are wider, irrelevant to left ventricular dysfunction and autonomic function of the heart.

[Right ventricle pacing site optimization guided by intracardiac echocardiography]. / Optymalizacja lokalizacji elektrody komorowej ukladu stymulujacego pod kontrola echokardiografii wewnatrzsercowej.

UNLABELLED: Right ventricle outflow tract (RVOT) is an alternative pacing site to right ventricle apex (RVA). Intracardiac echocardiography (ICE) is a new method for intracardiac structures visualization. THE AIM: is comparison of functional effects of DDD permanent ventricular pacing in patients with lead implanted in RVA or in RVOT with the use of traditional fluoroscopy or in RVOT guided by ICE. MATERIAL AND METHODS: 33 patients with AV block grade I/III no older than 75 y (mean age 65,9+/-0,3 years). Group 1: 10 patients with RVA lead implantation. Group II: 12 patients with leads implanted in RVOT with the use of ICE. Group IlI: 11 patients with lead positioned in RVOT with the use of fluoroscopy. High septum was established as an target pacing site for RVOT implantation. On 3 day and 3 months after implantation the following parameters were collected: VO2 max, 6-minute walking test distance, level of NT-proBNP. The comparison of relative changes was done, 3 month vs. 3 day for each parameter. RESULTS: Statistically significant greater decrease in NT-proBNP was found in Group II in comparison with both Group I and Ill (respectively p = 0.021 and p _ 0.034). Significantly greater increase in VO2 max was detected in patients Group II comparing to Group I (p = 0.047). Moreover it was found that ICE guided implantation is most effective in precise lead positioning. CONCLUSION: ICE guided lead localization on high interventricular septum seems to have better functional characteristics than other right ventricle pacing sites.

[Glycosylated hemoglobin and left ventricular diastolic dysfunction in patients with type 2 diabetes mellitus]. / Zaleznosc miedzy stezeniem hemoglobiny glikowanej a stopniem niewydolnosci rozkurczowej serca u chorych na cukrzyce typu 2.

UNLABELLED: Glycosylated hemoglobin (HbA1c) is a confirmed prognostic factor of cardiovascular complications in diabetic patients. The relative odds of cardiovascular disease (CD) increase by 20% for 1% increase of HbA1c above HbA1c 5%. The aim of the study was to assess relationship between diastolic dysfunction and HbA1c in patients with diabetes mellitus 2 (DM 2) without critical coronary stenosis in coronarography. MATERIAL AND METHODS: The study comprised 57 subjects (35 men and 22 women) with DM 2, without coronary stenosis in coronarography, with normal and elevated HbA1c levels. The subjects were divided into two groups depending on HbA1c level: with HbA1c < or = 6.1% and HbA1c >6.1%. Parameters of left ventricular diastolic function were assessed in echocardiography according to criterions of European Society of Cardiology. Subjects with decreased systolic function (EF<50%) were excluded from the study. RESULTS: Diastolic dysfunction of the left ventricle was observed in 43% of patients with HbA1c >6.1% comparing to 4.5% of patients in the group with HbA1 < or = 6.1%. In the group with HbA1c >6.1% in 38% of the patients abnormal relaxation in early filling phase and in 5% abnormal isovolumetric relaxation were observed. In the group with HbA1 < or = 6.1% in only 1 patient (4.5%) abnormal relaxation in early filling phase was observed. CONCLUSION: Diastolic function of the left ventricle in patients with diabetes is dependent on HbA1c levels.

[Detection of patients at risk for paroxysmal atrial fibrillation (PAF) by signal averaged P wave, standard ECG and echocardiography]. / Rozpoznawanie zagrozenia napadowym migotaniem przedsionków z wykorzystaniem analizy standardowego i usrednionego elektrokardiogramu oraz badania echokardiograficznego.

UNLABELLED: The aim of this study was to evaluate whether analysis of signal averaged P wave, together with left atrial diameter (LA) and P wave duration in surface ECG lead II (PII) allow to predict the risk of PAF. MATERIAL AND METHODS: Patients with coronary heart disease and/or hypertension were examined (n=145). They were divided into two groups 110 patients with PAF were compared with 35 patients without PAF Age (60,5 vs. 57,4 years) and LA size (39,8 vs. 3,7 mm) were similar in two groups. RESULTS: The root mean square voltage (RMS) for the last 10,20, 30 ms were calculated and for all of the filtered P wave (RMSW) were measured RMS ratio (RMSR) were calculated according to RMSW/ RMS20. Filtered P wave duration (PWD) and difference befteen PWD and P II (PWD-PII) were established. Most of the analyzed parameters were statistically significant (p<0,05). The statistical analyses made it possible to outline the score index evaluating how PAF reacts parameters. CONCLUSIONS: Score index evaluating of the PAF occurrence and its influence is statistically significant with sensitivity 86%, specificity 83,5% and index positive predictor 82,7% and index negative predictor 83,7%. The most significant parameters which detect the patients with the occurrence of PAF are PWD > or =130ms, RMS20<3, microV, RMS10<2,2 microV and PWD-PII > or =40 ms.

[The influence of weather conditions on the occurrence of paroxysmal atrial fibrillation]. / Wpllyw warunków atmosferycznych na wystepowanie napadowego migotania przedsionków.

UNLABELLED: The effect of the changing weather conditions on the incidence of the paroxysmal atrial fibrillation (PAF) has not been documented before. MATERIAL AND METHODS: This analysis retrospectively assessed the influence of the weather conditions on 1153 PAF cases over the period of 10 years. The average age of the studied population was 64.9 +/- 9.2 years. There was 60% males in the group. The majority (84%) had an existing heart disease, the remaining part was diagnosed as the lone PAF. RESULTS: The following factors favoured the FAP occurrence: high air temperature (> 25 Centigrade) for more than 3 days, low temperature (< 8 Centigrade), water vapor pressure > 16.5 kPa, accelerated increase of the air pressure > 8hPa over 2 days. CONCLUSIONS: The following weather conditions such as: temperature, air humidity and pressure have a definite impact on the occurrence of the paroxysmal atrial fibrillation episodes in 87% of patients especially those with co-existing coronary heart disease, hypertension or older age.

[The influence of myocardial infarction on depression in patients with coronary artery disease]. / Ocena wplywu przebytego zawalu miesnia sercowego na nasilenie depresji u chorych na chorobe niedokrwienna serca.

UNLABELLED: The recent studies revealed the relation between depression and the prevalence of cardio-vascular diseases, as well as their complications. However the correlation between the risk factors of coronary artery disease and depression in patients suffering from cardio-vascular disorders hasn't been sufficiently examined. The history of myocardial infarction (MI) is a well known factor, which increases mortality. The aim of the study was to determine if there was any relation between the history of myocardial infarction and depression rate in patients with cardio-vascular diseases. MATERIAL AND METHODS: The study involved 163 patients, 75 women and 88 men, aged 29 to 86 years (mean age 60.75 +/- 11.01), hospitalised for the purpose of undergoing coronary angiography or percutaneous transluminal coronary angioplasty (PTCA). Before the procedure, the symptoms of depression were evaluated in all the patients. Each of them filled the Beck's scale inquiry-sheet. Two groups of patients were detached: group A consisted of patients with the history of MI (n = 96), group B-of patients with negative history of MI, diabetes who had never undergone PCI, or coronary artery bypass graft (CABG) before (n = 42). The control group (group C) consisted of 75 individuals, aged 20 to 80 (mean age 45 +/- 11.14 y), who felt healthy according to WHO criteria, weren't on any medication, hadn't been hospitalised in previous 5 years (at any reason) and in whom cardio-vascular diseases and their modificable risk factors were excluded. RESULTS: The median of the Beck's score of depression for group A (9 points) was significantly higher (Wilcoxon test), than for group B (6.5 points), p < 0.02 and for the group C (3 points), p < 0.05. (tab. 1). CONCLUSIONS: In patients with cardio-vascular disorders depression is more frequent, than in health individuals. History of MI increases the prevalence of depression.

[Degenerative valvular and left ventricle structural changes in echocardiography in patients with rheumatoid arthritis]. / Cechy zwyrodnienia zastawek a zmiany struktury lewej komory serca w badaniu echokardiograficznym u chorych na reumatoidalne zapalenie stawów.

UNLABELLED: The disproportion between absence of clinical manifestations of circulatory system involvement and serious lesions in the heart found on post mortem examinations, more frequently diagnosed congestive circulatory failure and also higher mortality rate of patients with rheumatoid arthritis (RA), encouraged the authors to study the subject. THE AIM OF THE STUDY: Echocardiographic assessment of the effect of rheumatoid process on the heart in patients with RA without clinically overt features of heart disease. MATERIAL AND METHODS: The study was conducted in 50 patients with RA diagnosed on the basis of the American College of Rheumatology (ACR) criteria and in 50 persons matched with the patients with respect to age, gender, body area and body mass index, heart rate and arterial pressure. Persons with manifestations and/or history of cardiovascular diseases were excluded from the study. RESULTS AND CONCLUSION: The authors found that: in rheumatoid arthritis, the involvement of the heart by the pathological process is manifested as degenerative changes of valve leaflets, and these lesions correlate with interventricular septum thickness and the mass and mass index of the left ventricle.

Minimizing right ventricular pacing in patients with sinus node disease and prolonged PQ interval: The impact on exercise capacity.

BACKGROUND: Several clinical and experimental studies have shown that unnecessary right ventricular pacing in sinus node disease can be detrimental. Inter- and intra-ventricular asynchrony imposed by right ventricular pacing may cause reduction in contractility and relaxation of left ventricle, worsening mitral regurgitation, regional redistribution of myocardial perfusion and oxygen consumption, and asymmetrical hypertrophy of left ventricular wall. In some patients, sinus node disease coexists with impaired atrioventricular conduction. The optimal pacing mode in this population is not determined. Minimizing right ventricular pacing can preserve inter- and intra-ventricular synchrony. On the other hand, longer atrioventricular delay may cause atrioventricular asynchrony. The aim of this study was to prospectively assess the impact of minimizing right ventricular pacing in patients with DDD pacemaker implanted for sinus node disease and prolonged PQ interval on exercise capacity, cardiac function and quality of life. METHODS: The study enrolled 50 consecutive patients with prolonged PQ interval who were implanted with DDD pacemaker because of sinus node disease. Each patient was treated alternately with 2 pacing modes in random order for 4-month periods: conventional dualchamber pacing and dual-chamber minimal ventricular pacing (prolonged atrioventricular delay). At the end of each phase the following tests were performed: cardiopulmonary exercise testing, echocardiographic evaluation and quality of life assessment (SF36). RESULTS: There was no significant relationship between pacing mode and cardiopulmonary parameters, echocardiographic parameters and quality of life. CONCLUSIONS: Sequential atrioventricular pacing may be a reasonable choice for treating patients with sinus node disease and prolonged PQ interval.

Autonomic nervous system and left ventricular hypertrophy in essential hypertension.

BACKGROUND: Patients with essential hypertension (EH) and left ventricular hypertrophy (LVH) have an increased risk of cardio-vascular complications. Alterations in the autonomic nervous system (ANS) activity may play a role in the development of serious cardiac arrhythmias and mortality in these patients. AIM: To examine the activity of ANS in patients with established EH in relation to the presence of LVH. METHODS: The study group consisted of 70 subjects: 50 patients with untreated EH (mean age 44.4+/-12.7 years, 28 patients without LVH and 22 with LVH), and 20 age-matched healthy volunteers. ANS reactivity was assessed using heart rate variability (HRV) analysed during tilt table testing at 60 degrees. The following 5-min time-periods were analysed: (A) before tilting (supine position), (B) initial period of tilting, (C) last 5 min of tilting, and (D) immediately after completion of tilt test (after return to supine position). RESULTS: Patients with EH without LVH had a higher increase of LF/HF values (period B versus period C) compared with controls (p<0.05). The change from tilt to supine position caused significantly lower change in lnHF values in patients with EH and LVH than in controls (p<0.01) or patients with EH without LVH (p<0.005). In patients with EH and LVH a significant correlation between HF and LVmass/height (r=-0.5, p<0.01) was noted. Compared with healthy controls, patients with EH and LVH had significantly lower HRV parameters [lnLF values were significantly lower in all analysed periods, (p<0.05), and lnHF - during period D, (p<0.01)] whereas LF/HF ratio assessed during period D was significantly higher (p<0.05). CONCLUSIONS: In patients with EH without LVH a relative dominance of sympathetic activity is present. LVH in EH leads to a decrease in vagal drive and progressive inhibition of parasympathetic activity, both of which decrease HRV. These changes may play an important role in the electrical instability of hypertrophied myocardium.

Usefulness of patient's history and non-invasive electrocardiographic parameters in prediction of ajmaline test results in patients with suspected Brugada syndrome.

INTRODUCTION: The aim of the work was to assess the usefulness of patient's history and non-invasive electrocardiographic parameters in the prediction of ajmaline test results in patients with suspected Brugada syndrome. MATERIAL AND METHODS: The study involved a group of 59 patients (37 men) at average age of 31.6 ±12.2 years with suspected concealed form of Brugada syndrome. Pharmacological provocation with intravenous ajmaline administration was performed. The patients were divided into two groups depending on ajmaline test results. Individual and total predictive value for ajmaline test was based on the analysis of medical anamnesis and non-invasive electrocardiographic examination. RESULTS: The analysis carried out within the work indicated a special predictive value of 2 parameters which constituted the study inclusion criteria - family history of Brugada syndrome (28.6% vs. 3.8%; p = 0.0477) and occurrence of saddleback electrocardiographic changes in ECG curve (42.9% vs. 0.0%; p = 0.0002). Non-invasive electrocardiographic parameters which showed significant predictive value for ajmaline test were as follows: dispersion of QTc interval (prior to the provocation test 54.43 ±24.77 ms vs. 32.70 ±12.98 ms; p = 0.0005 and during daytime activity 46.81 ±27.16 ms vs. 32.07 ±13.19 ms; p = 0.0198), corrected QT intervals, Tpeak-Tend intervals in particular leads, QTpeak intervals, dispersion of Tpeak-Tend interval assessed from precordial leads (V1-V6) (42.86 ±13.80 ms vs. 26.54 ±11.70 ms; p = 0.001) and J-point elevation in V2 and V3 leads. CONCLUSIONS: Both interview and non-invasive electrocardiographic parameters which reflect cardiomyocyte repolarization disorders are of high predictive value in anticipating ajmaline pharmacological provocation results in patients with suspected Brugada syndrome.

Cognitive impairment after appropriate implantable cardioverter-defibrillator therapy for ventricular fibrillation.

BACKGROUND: Short periods of cerebral ischaemia during ventricular defibrillation testing may be associated with neuropsychological impairment. However, the impact of out-of-hospital ventricular fibrillation (VF) converted by implantable cardioverter-defibrillator (ICD) shock on cognitive functioning is unknown. AIM: To assess the impact of out-of-hospital VF converted by ICD shock on cognitive functioning. METHODS: The study included 52 primary prevention ICD recipients. Patients with a history of stroke or other neurological impairment, previous head injury and individuals unable to see or speak to complete neuropsychological tests were not included.Initially, a Mini-Mental State Examination was performed in all patients and one patient with a result below 24 points was excluded from the study. The cognitive battery consisted of four tests (six measurements): 1) the Digit Span subtest of Wechsler Adult Intelligence Scale-Revised; 2) the Digit Symbol subtest of Wechsler Adult Intelligence Scale-Revised; 3) the Halstead-Reitan Trail-Making Test A and B; and 4) the Ruff Figural Fluency Test. RESULTS: The mean time from ICD implantation to cognitive assessment was 26 months. During this period, 15 appropriate shocks for VF were observed in seven (14%) patients. The patients with appropriate ICD therapy were significantly worse in two out of the six neuropsychological measurements and had a significantly lower aggregate result. In multivariate linear regression analysis, defibrillation therapy was an independent factor of poor cognitive functioning, along with age and education. CONCLUSIONS: Short periods of out-of-hospital VF converted by ICD are associated with cognitive impairment in the recipients of primary prevention ICD.