[Interrelationship between polymorphic markers of methylenetetrahydrofolate reductase gene and development of acute disturbance of brain circulation in families of patients with atrial fibrillation].

In the present work we for the first time on the clinic-genetic material revealed genetic predictors of development of acute disturbance of brain circulation (ADBC) in families of patients with atrial fibrillation (AF) namely polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene. Genotype CC was significantly more often found among patients with AF and ADBC compared with controls (58.1 and 35.2%, respectively, p=0.02) as well as in relatives of probands compared with the control group (59.3 and 35.2%, respectively, p=0.008). With this in relatives with revealed paroxysmal AF and ADBC we also noted presence of CC genotype. Taking into consideration the relationship obtained between polymorphysms of MTHFR gene and AF it was possible to assume that polymorphic marker CC appeared to be a predictor of ADBC in these families.

[Combined use of left atrial transesophageal pacing and cordarone in atrial flutter]. / Sochetannoe primenenie chrezpishchevodnoi stimuliatsii levogo predserdiia i kordarona pri lechenii trepetaniia preserdii.

AIM: To investigate the effectiveness of superfrequent transesophageal left atrial stimulation (TLAS) and its combination with cordarone in management of atrial flutter (AF). MATERIALS AND METHODS: 650 patients with paroxysmal AF underwent TLAS. The paroxysm duration varied from 1 hour to 1 month. In 312 patients TLAS was performed prior to treatment with antiarrhythmic drugs (group 1), in 338 patients--after intravenous administration of cordarone (group 2). RESULTS: Superfrequent TLAS has restored sinus rhythm (SR) in 85(27.2%) and 169(50%) patients of groups 1 and 2, respectively (p < 0.001). TLAS promoted conversion of AF in atrial fibrillation (AFi) in 185(59.3%) and 159(47.1%) patients of groups 1 and 2, respectively (p < 0.01). Moreover, SR recovered 24-48 hours after TLAS in 87(27.9%) and 64(18.9%) patients of groups 1 and 2 respectively (p < 0.01). Sinus rhythm recovered in a total of 172(55.1%) and 233(69.0%) patients, AF was converted to AFi in a total of 88(31.4%) and 95(28.1%) patients (p > 0.05) of groups 1 and 2, respectively. TLAS was uneffective in 42(13.5%) and 10(2.9%) patients of groups 1 and 2, respectively. CONCLUSION: Superfrequent TLAS is a highly effective and non-invasive modality in the treatment of paroxysmal AF. It promotes recovery of SR. In some patients TLAS induces AFi which is more controllable by medication as regards the heart rate. Cordarone contributes to the response to TLAS in patients with paroxysmal AF.

[Use of transesophageal left atrial cardiac pacing for assessment of cordarone effectiveness in patients with atrioventricular tachycardia]. / Primenenie chrezpishchevodnoi stimuliatsii levogo predserdiia dlia otsenki éffektivnosti lecheniia kordaronom patsientov s atrioventrikuliarnymi takhikardiiami.

AIM: To assess by means of transesophageal left atrial pacing the effectiveness of cordarone treatment for arrhythmias caused by re-entry mechanism. MATERIALS AND METHODS: Effectiveness of cordarone treatment was estimated in 25 patients with atrioventricular nodal tachycardia (AVNT) and in 33 patients with WPW syndrome and reciprocal atrioventricular tachycardia (RAVT) with frequent paroxysms of tachycardia 1-5 times per week. Transesophageal left atrial pacing (TELAP) was performed before antiarrhythmic treatment and on cordarone treatment day 14-18. Cordarone was given for two months in common regimen (the first 10 days--600 mg/day, the next 10 days--400 mg/day and then 200 mg/day). RESULTS: The first TELAP induced paroxysmal AVNT or RAVT in all the patients. According to the results of the second TELAP, all the patients were divided into three groups. Group 1 included 28 patients in whom the second TELAP was unable to induce tachycardia. All these patients had increased effective refractory period (ERP) of AV node and/or of accessory pathway (AP) values and a decreased Wenkebach point (WP) < 150/min during the second TELAP in comparison with the first TELAP. All these patients had no spontaneous paroxysms of T during the 3-month follow-up. Group 2 included 18 patients in whom the second TELAP induced AVT lasting < 30 seconds. 16 of these patients had tachycardia with less heart rate during the second TELAP in comparison with the first TELAP, 153 + (-) 8 bpm vs 188 + (-) 10 bpm, p < 0.001, respectively. Also, in these 16 patients we found an increase of values of ERP of AV node and/or AP > 360 ms and a decrease of WP < 150 bmp. 14 of these 16 patients had no spontaneous paroxysms of AVT and 2 patients had short episodes of AVT during the 3-month follow-up with effects of vagal manoeuvers. From 2 other patients of group 2 one had short episodes of spontaneous T and one had long episodes of tachycardia with effect of verapamil i.v. Group 3 included 12 patients in whom the second TELAP induced the same AVT as the first TELAP. Values of ERP of AV node and/or AP and WP during the first and second TELAP were not different. All of these patients had long spontaneous paroxysms of AVT during cordarone treatment day 14-18. The treatment was discontinued in all patients of group 3. CONCLUSION: Cordarone is effective in prevention of AVT. Negative results in provocation of AVT during TELAP after 14-18 days of cordarone treatment is a very specific predictor of cordarone treatment effectiveness. Provocation by TELAP of short episodes of AVT with reduced heart rate and higher values of ERP of AV node and AP and lowering of WP < 150 bpm may not predict ineffectiveness of cordarone in patients with AVT. Moreover, the majority of these patients had no spontaneous episodes of AVT. Provocation by TELAP during cordarone treatment of the same AVT episodes as before cordarone treatment is a very specific predictor of cordarone effectiveness.

Combined transesophageal left atrial pacing and antiarrhythmic therapy in the treatment of atrial flutter.

In order to terminate atrial flutter (AF) overdrive transesophageal left atrial pacing (TELAP) was performed in 760 patients with paroxysmal AF. There were 315 women and 415 men (mean age 59 years). In 260 patients, TELAP was used in an outpatient setting. Approximately half of the patients (51%) had coronary artery disease and/or arterial hypertension, and 23% of the patients had no structural heart disease. The duration of AF ranged between 1 hour and 1 month. TELAP was performed in 312 patients without any antiarrhythmic drug (AAD) administration (group I) and in 448 patients after administration of AAD (procainamide and/or amiodarone) in conventional doses (group II). TELAP resulted in immediate return of sinus rhythm in 85 patients (27%) of group I and in 222 patients (50%) of group II (P < 0.001). TELAP converted AF to atrial fibrillation (AFIB) in 185 of group I and in 214 (48%) of the group II patients (P < 0.01). In addition, within 1-2 days after TELAP AFIB converted to sinus rhythm spontaneously or after AAD in 87 patients of group I (28%) and in 84 (19%) of the group II patients (P < 0.01). In general sinus rhythm was restored in 172 (55%) of the group I and in 306 (68%) of the group II patients (P < 0.005). AF was converted to AFIB in 98 (31%) of the group I and in 130 (29%) of the patients in group II patients (NS). TELAP was ineffective in 42 (13.5%) of the group I and in 12 (3%) of the group II patients (P < 0.001). TELAP was an effective noninvasive method for the treatment of recent onset AF. Our experience showed that after TELAP, sinus rhythm was restored in most of the patients with paroxysmal AF within 1-2 days. In some patients TELAP converted AF to AFIB, making it easier to control the heart rate with AAD. Treatment with AAD before TELAP increased its effectiveness.

[Significance of autonomic block by drugs for the diagnosis and evaluation of the pathogenesis of the sick sinus syndrome]. / Znachenie medikamentoznoi vegetativnoi blokady dlia diagnostiki i otsenki patogeneza sindroma slabosti sinusovogo uzla.

Altogether 65 patients with the sinoatrial node weakness syndrome (SANWS) and 48 patients with the heart pain syndrome (control group) were examined for a study of the corrected time of sinoatrial node function recovery (CTSNFR) and the time of sinoatrial conduction (TSAC) before and after medicamentous vegetative blockade (MVB). A considerable increase in CTSNFR and TSAC sensitivity after MVB was noted. In most of the SANWS patients CTSNFR after MVB was increased, TSAC was decreased. Elevated CTSNFR in the SANWS patients was determined by the effect of propranolol and atropine and was noted mainly during atrial stimulation with a high frequency (over 160 imp/min).