Issues - Journal of arrhythmology №74, 15/11/2013

Comparative analysis of catheter and surgical ablation of atrial fibrillation after failed endocardial pulmonary vein isolation

D.A. Elesin, A.B. Romanov, A.V. Bogachev-Prokofyev, D.V. Losik, S.A. Bayramova, A.A. Yakubov, A.G. Strelnikov, E.A. Pokushalov

To compare effectiveness and safety of catheter and surgical radiofrequency ablation (RFA) for treatment of patients with paroxysmal and persistent atrial fibrillation (AF) after failed primary endocardial pulmonary vein isolation (PVI), 64 patients were examined and treated. In the course of surgical RFA, radiofrequency application was initially made in the area of pulmonary vein ganglionic plexuses followed by passing around pulmonary veins using a dissector, with their subsequent isolation with the aid of bipolar clamp. The final step consisted in creation of two ablation lines from the right upper and lower pulmonary veins on the left atrial dome and inferior wall reaching the left pulmonary veins. In the radiofrequency catheter ablation subjects, access to the left atrium and pulmonary veins was achieved through the inter-atrial septum. Absence of electrical activity inside isolated pulmonary veins was the endpoint of circular PVI. In all patients with persistent AF, PVI was accompanied by creation of inter-collector line on the left atrium roof, as well as the mitral isthmus ablation.

The Reveal XT device was implanted subcutaneously in the left parasternal area. After 12 months of follow-up, 26 of 32 (81%) patients in the surgical RFA group were free of paroxysms AF/atrial flutter/atrial tachycardia, as opposed to 15 of 32 patients (47%) in the catheter RFA. The subjects of both groups did not take antiarrhythmics. Thus, the "video assistant" surgical RFA is more effective than catheter RFA. The incidence of serious adverse events was higher in the surgical RFA group as compared with the catheter RFA group during treatment of patients with paroxysmal and persistent AF after the failed primary endocardial PVI.

To compare effectiveness and safety of catheter and surgical radiofrequency ablation for treatment of patients with paroxysmal and persistent atrial fibrillation after failed primary endocardial pulmonary vein isolation, 64 patients aged 56.5±7 years were examined and treated.

Key words: atrial fibrillation, left atrium, pulmonary veins, radiofrequency catheter ablation, surgical ablation, thoracoscopy, atrial flutter, loop recorder.

Influence of extent of radiofrequency ablation on contractile function of left atrium and pulmonary veins

E.A. Khomenko, S.E. Mamchur, I.N. Mamchur, N.S. Bokhan, D.A. Shcherbinina

To assess the dynamics of the left atrium (LA) contractility in relation to the extent of radiofrequency ablation (RFA) for treatment of atrial fibrillation (AF), 66 patients aged 56.2±7.3 years were examined. The ratio of the myocardial area subjected to radiofrequency exposure to the total LA area was assessed in all patients upon termination of antral pulmonary vein isolation (APVI); it made up 27.8±4.1%. In Group I (n=36) APVI was accompanied by RFA in LA, as opposed to Group II (n=30). Transesophageal and transthoracic echocardiography was performed in all subjects before and immediately after RFA.

Worsening of contractility of the LA or pulmonary vein was revealed after RFA which included an altered transmitral flow velocity, the pulmonary vein flow, and an increased LA size and volume. The "pseudo-restriction" of the left ventricle filling and a decreased LA ejection fraction predominantly due to the passive phase were found. No statistically significant difference was found between the study groups for any index assessed during the study. "Expansion" of PVI area to a certain extent did not deteriorate intra-atrial hemodynamics, but further expansion led to alteration of the LA passive distensibility. This cut-off level was determined and made up 25% of the total LA area.

Thus, depression of the LA contractility occurs in the early post-operation period after antral PVI due to its passive ejection. Expansion of areas of isolation on the inter-atrial septum and the LA lateral crest improves effectiveness of the procedure but worsens the LA contractility if the injury area exceeds 25% of the total LA area.

To assess the dynamics of the left atrium contractility in relation to the extent of radiofrequency ablation, 76 patients (42 men, 34 women) aged 56.2±7.3 years with paroxysmal atrial fibrillation (n=22, 19%) and persistent atrial fibrillation (n=54, 71%) were examined and treated.

Key words: atrial fibrillation, radiofrequency ablation, antral isolation, pulmonary veins, left atrium, inter-atrial septum, contractility, echocardiography.

Ablation of ventricular tachyarrhythmia originating from the right ventricular outflow tract in patients without underlying heart disease

E.A. Ivanitsky, V.A. Sakovich, E.B. Kropotkin, S.N. Artemenko, V.V.Shabanov, R.T. Kamiev, A.G. Strelnikov, I.G. Stenin, D.V. Elesin, A.B. Romanov, E.A. Pokushalov

To assess effectiveness and safety of ablation of ventricular tachyarrhythmia (VTA) originating from the right ventricular outflow tract, 186 patients aged 37.2±19.4 years were examined and treated. The number of ventricular premature contractions (VPC) detected was 19,454±12,819. Sustained ventricular tachycardia (VT) was documented in 41 patients (22%); implantable cardioverters-defibrillators (ICD) were implanted in 21 patients (11.2%). Freedom of VPC/VT throughout the follow-up period after single or repetitive ablations was the study primary endpoint. The secondary study endpoints were as follows: complications of the procedure, the number of VPC, comparison of the data of patients with the normal and depressed ejection fraction of the left ventricle.

The following areas of the VPC/VT location in the right ventricular outflow tract were identified: anterior wall (n=28; 15%), posterior wall (n=26; 14%), septal wall (n=19, 10.2%), free, or lateral, wall (n=22, 11.8%), antero-septal (n=37, 19.9%), postero-septal wall (n=47, 25.3%), antero-lateral (n=2, 1.1%), and postero-lateral (n=5, 2.7%) walls. The effective ablation was performed in 181 subjects (97.3%). The ablative procedure was ineffective in 3 patients (1.6%) with the PVC location in the antero-septal wall and 2 patients (1.1%) with their postero-septal location. In the above patients (n=5, 2.7%), the left ventricular outflow tract mapping was carried out. The PVC/VT location in them was as follows: the left and right Valsalva sinus in 3 patients (1.6%) and 2 patients (1.1%), respectively. Ablation from the side of the left aortic sinus was effective in 1 patient. In other 4 patients, ablative applications were made from the side of both the right ventricular and left ventricular outflow tracts, but without effect. The late effectiveness of the procedure after the single ablation was 88.2%, after repetitive procedures, 95.7%, provided no antiarrhythmic therapy was taken.

To assess effectiveness and safety of ablation of ventricular tachyarrhythmia originating from the right ventricular outflow tract, the data of 186 consecutive patients aged 37.2±19.4 years were analyzed.

Key words: ventricular premature contractions, ventricular tachycardia, right ventricular outflow tract, radiofrequency catheter ablation, long-term follow-up, ECG Holter monitoring.

Assessment of effectiveness of ablation of ventricular tachyarrhythmia originating from the right ventricular inflow tract in patients without underlying heart disease

E.A. Ivanitsky, V.A. Sakovich, E.B. Kropotkin, D.B. Drobot, S.N. Artemenko, V.V.Shabanov, R.T. Kamiev, A.G. Strelnikov, I.G. Stenin, D.V. Elesin, A.B. Romanov, E.A. Pokushalov

To assess effectiveness and safety of radiofrequency ablation (RFA) of ventricular tachyarrhythmia (VTA) located in the right ventricular inflow tract, 32 patients aged 39.7±19.1 years were examined and treated. The number of ventricular premature contractions (PVC) detected was 17,642±13,475; sustained ventricular tachycardia (VT) was documented in 7 patients (21.9%); implantable cardioverters-defibrillators (ICD) were implanted in 4 patients (12.5%). Antiarrhythmic therapy was ineffective in all patients. RFA was performed using the NaviStar ThermoCool irrigated electrode, with the irrigation velocity of 17 ml/min, maximal power or 40 W, maximal temperature of 43°C, and the duration of each application of 40‑60 s. Freedom of VPC/VT throughout the follow-up period after single or repetitive ablations was the study primary endpoint. The secondary study endpoints were as follows: complications of the procedure and the number of VPC.

In 20 patients (62.5%), VTA originated from the tricuspid valve area and, in 12 patients (37.5%), from the basal part of the right ventricle. In 29 patients (90.6%), the only morphology of PVC/VT was revealed; 3 patients (9.4%) had polymorphous PVCs. The number of points for 3D reconstruction of the right ventricular inflow tract endocardial surface was 37±11. The normal endocardial voltage in the right ventricular inflow tract was revealed in all patients. The number of radiofrequency applications was 10.6±3.2, with the fluoroscopy exposure of 6.6±2.8 min and the procedure duration of 59.7±10.2 min. In 2 patients (6.2%), RFA was not performed because of parahisian location of PVs and a high risk of development of complete atrio-ventricular block. In one patient (3.1%) with the PVC/VT location in the free wall, the RFA in the right ventricle was ineffective. Thus, the overall effectiveness of RFA was 93.8% (30 patients). The late effectiveness of the procedure after the single ablation was 87.5%, after repetitive procedures, 93.8%.

Thus, RFA of VTA originating from the right ventricular inflow tract is a highly effective and safe technique of treatment which permits one to maintain the sinus rhythm during the entire follow-up period.

To assess effectiveness and safety of radiofrequency ablation of the substrate of ventricular tachyarrhythmia originating in the right ventricular inflow tract, 32 patients aged 39.7±19.1 years were examined and treated.

Key words: ventricular premature contractions, ventricular tachycardia, electro-anatomic mapping, radiofrequency catheter ablation, antiarrhythmic therapy, electrocardiogram, Holter monitoring.

Meta-analysis of the data on application of stress-tests in diagnosis of congenital long qt syndrome

L.A. Kalinin, M.A. Shkolnikova

To study the role of stress-tests in differential diagnosis of genetic types of congenital long QT syndrome, meta-analysis of the most valuable literature data was performed.

Key words: congenital long QT syndrome, bicycle test, treadmill-test, isoproterenol, mental stress, atrial pacing, meta-analysis.

Acute hemodynamic effect of cardiac resynchronization therapy in patients with chronic heart failure

V.A. Kuznetsov, N.N. Melnikov, D.V. Krinochkin, G.V. Kolunin, E.A. Gorbatenko

To assess acute hemodynamic effect of cardiac resynchronization therapy (CRT) in patients with chronic heart failure (CHF), 38 patients (including 35 men) aged 52.3±9.8 years were examined and treated. 20 patients had ischemic cardiomyopathy (ICMP) and 18 ones, non-ischemic cardiomyopathy (NCMP) with CHF of functional class III‑IV (NYHA), depressed left ventricular ejection fraction (LV EF) below 35%, signs of intra-ventricular and/or inter-ventricular dyssynchrony revealed using echocardiography, taken the QRS complex width into the account. Coronary angiography was performed to all patients before the procedure. All patients received medical treatment in accordance with the current guidelines. 27 patients had the sinus rhythm and 11 subjects, chronic atrial fibrillation. In 23 patients, the combined systems were implanted (CRT devices with the cardioverter-defibrillator function). The device implantation was effective in all patients and occurred without complications. Before and after CRT, 6‑minute walk test was carried out. To assess hemodynamic parameters, the IE‑33 system was used (Philips, USA). Echocardiography was performed before and on the 3^rd day after the pacemaker implantation.

At the background of CRT the distance walked during 6‑minute walk test improved from 328±93 m to 397±75 m, p<0.001; a statistically significant improvement of CHF was revealed (NYHA classification), a significant increase in LV EF from the baseline occurred, the dP/dt index increased, and both end diastolic and end systolic volumes deceased. The CHF functional class (NYHA) improved in 29 patients (76%), an increase in the 6‑minute walk test distance of ≥10% took place in 16 subjects (52%), ejection fraction increased by more than 5% in 27 patients (71%), and a decrease in end systolic volume occurred in 26 patients (68%). The correlation analysis showed an evident significant correlation between changes in end systolic volume and LV EF (r=0.659; p<0.001) and between changes in CHF functional class and LV EF (r=0.324; p=0.047). When analyzing the patient groups with the different QRS complex width, no significant difference was revealed in the CHF functional class (p=0.88), 6‑minute walk test distance (p=0.51), changes in LV EF (p=0.74), and the end systolic volume of the left ventricle (p=0.11). Thus, positive changes in the cardiac hemodynamics and physical working capacity are detected after the CRT device implantation even during hospitalization.

To assess acute hemodynamic effect of cardiac resynchronization therapy in patients with chronic heart failure, 38 patients (including 35 men) aged 52.3±9.8 years were examined and treated.

Key words: cardiac resynchronization therapy, chronic heart failure, dyssynchrony, mitral regurgitation, 6‑minute walk test, echocardiography.

Review

Electrophysiological methods of treatment of hypertrophic cardiomyopathy

V.A. Kuznetsov, Yu.A. Yurkina

Potentialities of application of dual-chamber cardiac pacing, cardiac resynchronization therapy, and implantable carioverters-defibrillators in treatment of patients with hypertrophic cardiomyopathy are considered.

Key words: hypertrophic cardiomyopathy, left ventricle outflow tract, inter-ventricular septum, cardiac pacing, cardiac resynchronization therapy, implantable carioverter-defibrillator.

Electrophysiological mechanisms and results of interventional treatment of patients with atrial tachycardia and atrial fibrillation originating from pulmonary veins

A.L. Labazanova, E.A. Artyukhina

To study electrophysiological mechanisms and assess early and late outcomes of interventional treatment in patients with atrial tachycardia (AT) originating from the pulmonary vein (PV) ostia and paroxysmal atrial fibrillation (AF), 100 patients were examined. The study group consisted of 60 patients aged 43.5±12.19 years (16‑65 years), 33 men (55%) and 27 women (45%), including 2 pediatric patients under 18 years (3.3%), with ectopic AT from PV. The arrhythmic history was 5.7±4.3 years (0.5‑20 years). In the study group, 64 procedures were performed (1.06±0.06 patients per 1 patient). The control group consisted of 40 patients with paroxysmal AF due to the chaotic activity of PV aged 48.1±11.9 years (16‑72 years), 32 men (80%) and 8 women (20%), including 1 pediatric patient under 18 years (2.5%). The arrhythmic history was 6.2±6.5 years. In the control group, 50 procedures were made (1.25±0.07 procedures per 1 patient). The transseptal puncture was performed in all patients for access to the left atrium (LA). Electrophysiological properties of the PV muscular muffs as well as the LV arrhythmogenicity were studied. For this purpose, 20‑polar Lasso catheter was positioned in the PV ostium, and the PV spikes were recorded. The duration of radiofrequency ablation (RFA) was 15.1±10.5 min (9­‑30 min) for one PV. After RFA of ostia of all PVs, their electrophysiological properties were compared (effective and functional refractory periods, probability of AF induction in an isolated PV, fragmented activity, duration of impulse conduction in PV) and repetitive PV angiography was performed to reveal their stenosis.

The outcomes of RFA were assessed in the early, intermediate, and late post-intervention periods. In the early post-intervention period, the effectiveness in both groups was 100%; at discharge, all patients had the sinus rhythm and received antiarrhythmic and anticoagulant therapy discontinued 3 months later. Six months after the intervention, the AT recurrence was documented in 4 patients (6.6%) which required an additional interventional procedure. In the control group, recurrence of arrhythmia was revealed in 10 patients (25%). In the late post-intervention period (39.1±9.5 months), the overall effectiveness in patients with AT, taking repetitive procedures into the account, was 100%, as compared with 87% in the AF group.

Thus, computed tomography of LA and PV, 12‑canal Holter monitoring, and non-invasive electrophysiological mapping in the pre-intervention period permit one to reveal peculiar features of the LA and PV structure with a high accuracy. The tachycardia recurrence in the control group (25%), with two or more PVs being source of automaticity, are revealed significantly more frequently than in the study group (6.6%), where a single ectopic focus was predominantly a source of automaticity. The radiofrequency PV ostia isolation is a highly effective method of treatment of patients with ectopic AT originating from PV ostia and paroxysmal AF.

A new technique of activation mapping based on digital reconstruction of bipolar electrograms, assessment of direction of myocardial activation, and activation mapping is studied to be used in systems of non-invasive electrocardiographic visualization.

Key words: reverse problem of electrocardiography, non-invasive electrocardiographic visualization, activation mapping, bipolar electrograms, direction of myocardial activation, catheter ablation.

Ultrasound mapping for ablation of post-infarction ventricular re-entry tachycardia: first experience in russia

S.E. Mamchur, E.A. Khomenko, N.S. Bokhan, I.N. Mamchur

To assess the results of mapping and radiofrequency ablation (RFA) of post-infarction ventricular re-entry tachycardia (VT) using the CartoSound program module, 20 patients aged 51.1±6.3 years were examined. In 8 patients of Group I, 9 procedures using the CartoSound system were performed. In 12 patients of Group II, 18 procedures using the commonly accepted mapping techniques were carried out. The SoundStar catheter was installed into the right ventricle to permit visualization of all parts of the left ventricle (LV). Ultrasound images were synchronized with the R-wave of surface ECG. Three-dimensional maps of LV and, separately, scar maps were constructed.

The time required for the LV map construction considerably diminished from the first to the eighth patient: from 24.8 min (17.4‑27.2 min) in the first four cases to 19.1 min (14.1‑21.2 min; p=0.04) in the last cases. The number of recurrences in Group II was several times higher than in Group I; however, the difference was statistically insignificant, probably due to the small sample. In 2 of 6 recurrences in Group II and the only case of recurrence in Group I, repetitive procedures were performed using the CartoSound system and in other cases, using the amplitude mapping only. There were no adverse events in Group I. In Group II, one adverse event was observed, transitory ischemic attack during the primary ablation. As an alternative approach to the LV and scar assessment, magnetic resonance tomography can be considered; however, despite appropriate visualization properties, the latter has a number of significant limitations. The weakest point is a delay between tomography and RFA procedure which can be 24 hours or more. Thus, ultrasound mapping is a more effective, safe, and accurate technique of anatomical mapping of post-infarction tachycardia as compared with amplitude mapping.

To assess the results of mapping and radiofrequency ablation of post-infarction ventricular re-entry tachycardia using the CartoSound program module, 20 patients aged 51.1±6.3 years were examined and treated.

Key words: intracardiac ultrasound mapping, three-dimensional mapping, ventricular tachycardia, post-infarction cardiosclerosis, radiofrequency catheter ablation.

Does early activation of patients after pacemaker implantation affect the rate of post-intervention complications?

N.V. Makarova, S.S. Durmanov, A.V. Kozlov, R.V. Morozov

To study two approaches to the patient activation after primary implantation of single- and dual-chamber pacemakers, 259 patients aged 17‑90 years including 80 patients with the early activation and 179 ones with the "standard" activation were examined and treated. The study group did not significantly differ. In the group with the "standard" activation, the patients were requested to stay in bed for 18‑20 hours; the patients were strongly recommended to stand up, stay in edgewise position; the patients ate supine, with an elevated head of the bed. The patients with an early activation were allowed to leave the bed 3 hours following the implantation and to eat in the sitting position. The patients of both groups were recommended to restrict hand movements at the side of implantation. No additional devices for shoulder immobilization at the side of implantation were used. X-ray assessment was performed intra-operatively immediately after the pacemaker implantation and one day later. Pacing parameters were assessed one day after implantation and before discharge from hospital.

Adverse events related to the pacemaker implantation were observed in 18 patients (6.9%). The electrode dislocation the pacemaker area hematomas were revealed. The early activation did not affect the development of the pacemaker area hematomas (p=0.75). The electrode dislocation was noted in 1.9% of cases. The pacemaker area complications such as a clinically significant hematoma were found in 5% of cases. The incidence of adverse events did not differ in the groups with the early and "standard" activation. No repetitive procedures were required. Thus, no significant difference in the incidence and nature of early post-intervention were revealed; the early activation is deemed to be a safe and well-grounded procedure.

To study the effect of the time of subject activation after the primary implantation of single- and dual-chamber pacemakers on the risk of adverse events, 259 patients aged 17‑90 years were examined.

Key words: pacemaker implantation, bed regime, electrode dyslocation, hematoma, anticoagulants, disaggregants.

Clinical study report

Potentialities of non-invasive surface electrocardiographic mapping in treatment of a patient with atrial fibrillation

E.S. Kotanova, O.V. Sopov, E.Z. Labartkava, E.I. Neznamova

A clinical case report is given of a 36‑year‑old patient, in whom during treatment of atrial fibrillation, the technique of surface electrocardiographic mapping was used, which permitted one to reveal an area with high-frequency chaotic organized activity.

Key words: atrial fibrillation, non-invasive surface electrocardiographic mapping, high-frequency chaotic activity, electrophysiological study.

Guidance to practinioners

Remote monitoring of patients: results of clinical trials

N.N. Lomidze, A.Sh. Revishvili, V.V. Kuptsov, A.A. Spiridonov

The perspectives are considered to use remote access in monitoring patients with implanted devices; the results of randomized clinical trials are analyzed; the authors' data are given.

Key words: remote monitoring, cardiac pacemaker, implantable cardioverter-defibrillator, cardiac resynchronization therapy, device programming, intra-cardiac electrodes.

Letters to editorial board

A case of induction of torsade de pointes during elimination of atrial fibrillation

M.V. Berman, N.S. Sokurenko, T.V. Kryatova, M.M. Medvedev

Paroxysmal ventricular tachycardia during transesophageal electrophysiological study

A.Yu.Rychkov, N.Yu. Khorkova

Российский Научно-Практический
рецензируемый журнал
ISSN 1561-8641

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