[Association of Polymorphic Genome Variants in the 2q32.1 Locus with the Development of Vasovagal Syncope].

The vasovagal syncope (VVS) is the most common form of syncope. The mechanisms of VVS development are not entirely clear. It is known that there is a genetic predisposition to this disease, but the data on the roles of individual genes are quite contradictory. Recently, a genome-wide association study identified a locus at chromosome 2q32.1 associated with a united group of diseases, that is, syncope and collapse; among the single nucleotide polymorphisms (SNPs) of this locus, the most significant association was observed for rs12465214. In a homogeneous sample of patients diagnosed with VVS, we analyzed the association of rs12465214, rs12621296, rs17582219 and rs1344706 located on chromosome 2q32.1 with this form of syncope. In the enrolled set, only rs12621296 was associated with VVS by itself, whereas associations of other SNPs were observed only in biallelic combinations. An epistatic interaction between the components of the combination rs12621296*A + rs17582219*A was revealed. The possible involvement of individual genes on the 2q32.1 locus in the genetic architecture of the VVS is discussed.

[Adherence and efficacy of long-term PAP therapy in patients with sleep-related breathing disorders associated with cardiac conduction disorders].

AIM: To study the effectiveness of prolonged use of PAP therapy (positive airway pressure therapy) in eliminating sleep respiratory disorders and associated cardiac conduction disturbances. MATERIALS AND METHODS: We included 21 patients who were examined at the Myasnikov Institute of Clinical Cardiology, National Medical Research Center of Cardiology, regarding cardiac rhythm and conduction disturbances, as well as obstructive sleep apnea and who have been on PAP therapy for more than 12 months. The average age was 66.5 [63.5; 73.2] years, body mass index 33.0 [30.2; 38.5] kg/m2, apnea-hypopnea index 65.0 [59.0; 86.3]/h. At the time of analysis, 15 patients continued to use PAP therapy (mean time of use: 6.0 years [4.7; 9.2]) and 6 patients refused long-term use of PAP therapy, mean time to use PAP therapy until failure amounted to 2.82.1 years. RESULTS: PAP therapy lead to a persistent decrease in apnea-hypopnea index of 63.6/h to 3.7/h was (p=0.0002). 86% of patients met the criteria for adherence to PAP therapy (use 4 hours/night, more than 70% of nights). Initially, before the use of PAP therapy, all cardiac conduction disorders were during sleep and exceeded 3 seconds, with fluctuations from 3.1 to 10.6 seconds. PAP therapy appeared to be effective in all patients: no asystoles, duration of more than 3 seconds, were detected. CONCLUSION: In obstructive sleep apnea patients with concomitant nighttime cardiac conduction disturbances, the long-term use of PAP therapy is effective and with good adherence.

[Lifestyle Modification as a Method of Treatment of Vasovagal Syncope].

Vasovagal syncope is the most common cause for loss of consciousness. The need for treatment of this condition is warranted by impaired quality of life and a risk of trauma due to the fall. At present, there are no medications with proven preventive effectiveness for vasovagal syncope as demonstrated by large randomized, placebo-controlled studies.  At the same time, information about the pathogenesis of vasovagal reaction and provoking factors allows effective use of non-drug methods (such as patient education, physical exercise, maneuvers) in the management of patients with vasovagal syncope.

[Recent advances in diagnosis and management of atrial fibrillation].

Alterations of heart rhythm are a common clinical event. They can be caused by almost any kind of heart disorder. Atrial fibrillation (AF) is the most common type of abnormal heart rhythm. Prevalence of AF in the general population is 1-2%, and given that AF incidence rate continues to increase it can be predicted that the number of patients will be doubled within the next 50 years. This review provides the most recent diagnostic and treatment methods, including both unique domestic antiarrhythmic drugs and non - drug methods for AF treatment which were developed and implemented in clinical practice at NMRC of Cardiology of the Ministry of Health of the Russian Federation.

[Differential Diagnostics of Vasovagal Fainting, Orthostatic Hypotension and Baroreflex Failure in a Patient With Syncope].

We present here a case report of recurring fainting due to orthostatic hypotension in a 45­year-old woman with Hodgkin's' disease, treated by radiation therapy and resection of cervical lymph node. We discuss difficulties of identification of etiology and mechanisms of orthostatic hypotension as well as possible role of baroreflex failure at the background of the Hodgkin's' disease treatment, and vasovagal syncope of which the patient suffered in her youth.

[Atrial fibrillation and prolonged nocturnal cardiac arrests in a patient with obstructive sleep apnea syndrome. Successful correction of disorders by CPAP therapy]. / Fibrillyatsiya predserdii i dlitel'nye nochnye «ostanovki¼ serdtsa u bol'nogo s sindromom obstruktivnogo apnoe vo sne. Uspeshnaya korrektsiya narushenii pri primenenii SIPAP-terapii.

The case history of a 46-year-old patient with obstructive sleep apnea syndrome was analyzed. The examination revealed fourth-degree obesity, prior myocardial infarction, persistent atrial fibrillation with nocturnal asystoles lasting as long as 14.3 sec. During selected drug therapy and regular application of secondary ventilation (continuous positive airway pressure (CPAP) therapy) used to correct breathing problems, there was a reduction in the signs of circulatory deficiency, cessation of cardiac pauses, and recovery of sinus rhythm. The therapeutic effect persisted during a 24-month follow-up.

[Results of using the dosing Valsalva-Weber test to determine autonomic disorders in patients with vasovagal syncope].

AIM: To estimate the value of the dosing Valsalva-Weber test (VWT) in the diagnosis of autonomic disorders in patients with vasovagal syncope (VVS). SUBJECTS AND METHODS: The dosing VWT using a specialized Task Force Monitor unit ("CNSystem", Austria) with synchronous noninvasive ECG and blood pressure (BP) monitoring was carried out in 30 patients (mean age 32 ± 14 years) with VVS and 12 healthy individuals (31 ± 7 years). The analysis of the test results encompassed the visual assessment of BP change curves and heart rate in different test phases and the calculation of pressure indices, Valsalva coefficient, arterial baroreflex sensitivity, and other parameters (a total of 26). RESULTS: The abnormally changed form of the mean BP curve, which was characterized by that BP by the end of Phase II test failed to achieve the baseline level, was recorded in 10 (33%) patients with VVS and in none of the healthy individuals (p = 0.04). An individual analysis of the gender- and age-adjusted Valsalva coefficient revealed its reduction in 9 (30%) patients while this indicator was within the normal range in all the healthy individuals (p = 0.04). CONCLUSION: During the dosing VWT, the signs of sympathetic insufficiency (impaired adrenergic regulation of BP) are found in 33% of the patients with VVS and those of parasympathetic insufficiency (impaired vagus regulation of cardiochronotropic function) are in 30%.

[Treatment of patients with long nocturnal asystoles and obstructive sleep apnea syndrome by creating continuous positive air pressure in the upper respiratory tract].

AIM: To study prevalence of obstructive sleep apnea syndrome (OSAS) in patients with nocturnal asystoles, and assess therapeutic efficiency of constant positive air pressure (CPAP) applied to upper respiratory tract in this category of patients. METHODS: The study incorporated 37 patients (33 men and 4 women, average age 50+/-11 years) with nocturnal heart beat interruptions of over 3 seconds. Baseline examination revealed grade II-III arterial hypertension in 67.5%, coronary heart disease - in 19%, diabetes mellitus in 8% and no cardiovascular disease - in 5.5% of patients. Sinus rhythm was registered in 30 (81%) of patients, 7 (19%) patients had permanent atrial fibrillation. Causes of deteriorated cardiac conduction were as follows: sinoatrial blocks and sinoatrial arrests (n=18), grade II-III atrio ventricular block (n=10), combination of these forms of bradyarrhythmias (n=2) and block of conduction to ventricles in permanent atrial fibrillation (n=7). According to intra esophageal cardiac pacing, the function of sinus node and atrio ventricular conduction appeared to be undisturbed in all patients with sinus rhythm. All patients have undergone polysomnographic (PSG) examination. For patients with OSAS, an individual selection of therapeutic pressure was carried out using the CPAP apparatuses. CPAP therapy was considered effective against OSAS if normalization of apnea/hypopnea index (AHI) was observed. RESULTS: OSAS was registered in 25 cases (68%) (mean AHI 54.9+/-28.7), 20 patients (80%) had severe grade of the syndrome. CPAP therapy appeared to be effective in all patients. At the background of treatment AHI decreased from 60.7 to 5.5 episodes per hour of sleep, mean oxygen saturation of arterial blood rose from 74 to 90%. Effect of CPAP therapy relative to cardiac conduction abnormalities was attained in all 19 patients with sinus rhythm and only in one patient with permanent atrial fibrillation. CONCLUSION: OSAS was revealed in 68% of patients with nocturnal bradyarrhythmias. Individually selected therapy with constant positive pressure in patients with nocturnal asystoles and OSAS efficiently eliminated in sleep asystoles and made it possible to avoid pacemaker implantation in some patients.

[Spectral indices of heart rate variability in patients with vasovagal syncopes according to evidence of 5-min ECG].

AIM: To compare autonomic nervous system activity estimated by power spectral analysis of heart rate variability in patients with vasovagal syncopes and healthy volunteers. MATERIAL AND METHODS: Seventeen health volunteers and 25 patients with vasovagal syncope were included in the study. In 16 cases faints were induced by head-up tilt table test (HTT), in 9 cases--by bicycle exercise test (BET). Power spectral analysis of heart rate variability in 5-th min ECG records was performed in supine and upright position while breath was fixed. RESULTS: In supine position the data of low frequency (LF) and high frequency (HF) of spectral power in both groups of patients were significantly higher than in volunteers. During upright the HF of spectral power significantly decreased in patients and volunteers. In upright position LF of spectral power significantly decreased in patients with syncope induced by HTT, did not change in patients with syncope induced by BET, but significantly increased in volunteers. CONCLUSION: Patients with vasovagal syncope had abnormal autonomic nervous system activity: a high level of parasympathetic influence in supine position and poor reaction of sympathetic nervous system during upright.

[Observation and provocation in diagnostics of syncope].

Despite a large number of modern examination techniques, possibilities for differential diagnostics of syncope remain limited even at the beginning of the 21st century. Up to 35% of patients get discharged from hospitals without knowing the exact nature of loss of consciousness. The main reason for this is that a syncopal attack is a symptom of a range of diseases and conditions, and a large number of examination methods may be necessary to establish its cause. One group of methods helps find the supposed morphological substrate of attacks, while other methods serve as evidence of its pathogenetic mechanism. What is their real diagnostic value? And which strategy--waiting for a spontaneous attack and observing it or provocation of syncope--is the best one when a patient with syncope is being examined? The article discusses advantages and disadvantages of diagnostic methods that are commonly used in diagnostics of reasons for loss of consciousness.

[Efficasy of compression therapy of the lower limbs in the treatment of patients with vasovagal syncopes].

AIM: To study efficacy and tolerance of compressive textile in the treatment of vasovagal syncopes. MATERIAL AND METHODS: The trial included 9 patients with recurrent vasovagal syncopes confirmed at bicycle exercise tests. The patients wore long medical stockings (Sigvaris, Ganzoni & Cie AG, compression of class II). The textile was tailored individually in all the patients. The effect of wearing stockings was tested at bicycle exercise (two tests before wearing to the syncope, one test 1-3 days after the second test upon 1 hour of wearing the stockings). RESULTS: None of the bicycle exercise tests done in the stockings was accompanied with syncopes. None of the patients experienced discomfort while putting on, wearing the stockings or performing the exercise. CONCLUSION: Good therapeutic effects and tolerance were registered when wearing therapeutic textile.

[New approaches to treatment of bradyarrhythmia in patients with obstructive sleep apnea syndrome].

AIM: To confirm or reject effects of CPAP on sleep asystole and to elucidate possible dependence on correction of respiratory disorders. MATERIAL AND METHODS: Thirteen patients (11 males and 2 females aged 19 to 66 years) with bradyarrhythmia (BA) arising in sleep participated in the study. BA was caused by transient atrioventricular block of the degree II-III in 9 cases (69%), episodes of sinus node arrest and/or synoatrial block in 6 (46%) cases. Two (15%) patients had combination of BA forms. To diagnose sleep respiratory disorders, polysomnography (PSG) was made. Diagnostic criteria of sleep obstructive apnea syndrome (SOAS) were apnea/hypopnea index (AHI) more than 5 episodes for 1 hour sleep. The patients were divided into two groups. Individual selection of therapeutic pressure under PSG control was performed in SOAS patients (the study group). CPAP-therapy was effective in AHI < 5. In the control group (AHI < 5) such selection was made too. CPAP-therapy was effective in the controls if episodes of apnea/hypopnea were not registered through the night of monitoring. RESULTS: In the study group CPAP-therapy was effective. The AHI decreased from 73.2 to 4.4, oxygen saturation of arterial blood increased from 74 to 85%, mean duration of asystoles fell from 5.2 to 1.3 s, pauses with duration more than 2 s disappeared. In the control group sleep apnea/hypopnea episodes disappeared but in asystole CPAP was uneffective. CONCLUSION: CPAP-therapy is effective and pathogenetically sound method of treating patients with nocturnal bradyarrhythmia associated with sleep respiratory disorders.

[Comparative efficacy and tolerance of atenolol and midodrine in patients with vasovagal syncopes].

AIM: To compare efficacy and tolerance of atenolol and midodrine in patients with vasovagal syncopes (VVS). MATERIAL AND METHODS: The trial included 35 patients with recurrent VVS confirmed at long passive head-up tilt table test (HTTT) or maximal load bicycle exercise test (MET). These tests were also used for assessing efficacy of atenolol and midodrine in cases when syncopes occur in repeated tests. If recurrent induction of VVS was absent, efficacy of the drugs was assessed by long-term (up to 12 months) clinical observation. Long-term administration of atenolol and midodrine was continued in patients with effect by HTTT and/or MET. Eighteen patients were randomized to take atenolol in a daily dose up to 50 mg, seventeen--to take midodrine in a daily dose up to 15 mg. RESULTS: Efficacy of atenolol by HTTT and MET was 8%, midodrine--57% (p = 0.01). All the patients benefited from the drugs in their long-term regimen. Long-term administration of atenolol induced remission of VVS in 82% cases, midodrine--in 89% (insignificant). Overall efficacy of atenolol was 44%, of midodrine--70% (insignificant). In 5 of 6 patients resistant to atenolol and midodrine monotherapy, combined use of the drugs was effective. Treatment with atenolol, midodrine and their combination prevented VVS in 89% patients. Both short- and long-term courses of atenolol and midodrine were safe in terms of side effects. CONCLUSION: Atenolol and midodrine as well as their combination were highly effective and well tolerated in the treatment of VVS patients.

[Successful midodrin treatment for vasovagal syncopes accompanied by asystole]. / Uspechnoe lechenie midodrinom vazovagal'nykh obmorokov, protekaiushchikh s asistoliei.

Vasovagal syncopes (WS) are fainting fits whose manifestations are systemic vasodilation and bradycardia. The development of WS is frequently accompanied by short-term cardiac arrest. Recent data show that implantation of a cardiac pacemaker fails to prevent the development of fainting fits in these patients. On the basis of the pathogenesis of WS, the use of alpha-adrenomimetic midodrine is justifiable. The presented case demonstrates the successful use of the agent in the treatment of vasovagal syncope accompanied by asystole.

[Results of midodrin treatment of vasovagal syncope]. / Rezul'taty primeneniia midodrida dla lecheniia bolnykh vazovagal'nymi obmorokami.

AIM: To elicit efficacy of midodrin in patients with vasovagal syncope. MATERIAL AND METHODS: 50 patients with recurrent vasovagal syncope documented by head-up tilt tests or bicycle exercise stress tests participated in the study. These tests controlled the effects of midodrin if syncopes occurred again in repetition of the tests. In the other patients the effect of the drug was assessed clinically. All the patients received midodrin in daily dose up to 15 mg. RESULTS: Mirodrin effectively prevented syncope in 13 (72%) patients as shown by the tilt test, in 10 (59%) patients as shown by the exercise stress tests and in 14 (93%) patients as controlled clinically. Total efficacy of midodrin was 74% (37 of 50 patients). CONCLUSION: Midodrin demonstrated high efficacy in prevention of vasovagal syncope. Side effects were not serious therefore the drug is well tolerated.

[Long-term orthostatic and bicycle ergometry exercise tests in differential diagnosis of syncopal conditions of unclear origin]. / Vozmozgnosti dlitel'noi ortostaticheskoi i veloérgometricheskoi prob pri differentsial'noi diagnostike sinkopal'nykh sostoianii neiasnogo geneza.

AIM: To study efficiency of bicycle exercise test and long-term orthostatic test in differential diagnosis of syncopes. MATERIAL AND METHODS: The study included 113 patients suffering from recurrent syncopes of unclear origin. Twelve healthy volunteers were selected for assessment of the tests specificity. All the patients and controls were examined by means of long-term orthostatic test (LTOT) and bicycle exercise test (BET). RESULTS: Specificity of both tests was 100%. In LTOT syncopes were observed in 52 (46%) cases, including vasovagal syncopes (51 patients), epileptic seizure (1 patient). BET induced vasovagal syncopes in 54 (48%) patients. The results of both tests by inducing syncopes coincided in 30 (26%) cases. In 24 (21%) patients syncopes occurred only in BET while LTOT appeared uninformative. In 21 (18.6%) cases syncopes occurred only in LTOT while BET produced a negative result. 38 (34%) patients had syncopes neither in LTOT nor BET. Both tests induced syncopes in 75 (66%) patients. No complications were observed. CONCLUSION: LTOT and BET are safe and complementary methods in differential diagnosis of syncopes.