Radiofrequency Ablation Of Atrial Tachycardia Research Articles

Electrophysiologic characteristics and outcomes of atrial tachycardia ablation after mitral valve surgery

Abstract Background Atrial tachycardia (AT) is a commonly encountered rhythm disorder in patients with mitral valvular (MV) surgery. Radiofrequency (RF) ablation is the preferred therapeutic option in symptomatic patients. Purpose We aimed to evaluate the characteristics and ablation outcomes of AT in patients with previous mitral valve (MV) surgery. Methods A total of 100 symptomatic patients [mean age: 56 ±12, gender: 56 (56%) female] with documented AT were enrolled. Activation mapping was performed during tachycardia in all patients as well as entrainment mapping when needed. Voltage mapping was performed in sinus rhythm in the related atrium. Low voltage areas and signals with continuous-fragmented morphology were also tagged. Results In 127 procedures, a total of 158 ATs were documented [59 (37.3%) ATs were right-sided, 95 (60.1%) ATs were left-sided and 4(2.5%) AT was biatrial]. Mean number of ATs per procedure was 1.2±0.6. Macroreentry was the primary mechanism in right and left atrium (83.1% and 63.1%, respectively). Cavo-tricuspid isthmus (CTI) dependent macroreentry was the most frequent mechanism in right ATs whereas perimitral reentry was the most common mechanism in left ATs. Atrial low voltage zones comprised 45.5±25.1 % of total left atrium. The acute procedural success was 95.2%. Freedom from ATa after index procedure was 80% at 12 months and 65.6 % at 24 months. After multiple procedures, freedom from ATa was 77% during the mean follow-up duration of 39.7 ± 27.2 months. Conclusion Left ATs are more common compared to the right ATs and macroreentry is the major mechanism in both right & left ATs. RF ablation of ATs has favourable long-term outcomes in patients with MV surgery.

Catheter ablation of atrial fibrillation using 2nd-generation cryoballoon in congenital heart disease patients — significance of RF ablation of additional atrial macro-reentrant tachycardia

BackgroundPrevalence of atrial fibrillation (AF) is increasing in adult patients with congenital heart disease (CHD). Experience using the cryoballoon to achieve pulmonary vein isolation (PVI) in adult CHD patients is limited. The aim of the present study was to assess the value of PVI by cryoballoon in adult CHD patients and to evaluate the significance of additional radiofrequency (RF) ablation of atrial tachycardia (AT).Patients and methodsProspective data analysis; all patients with CHD and AF and PVI using the cryoballoon from January 2017 through November 2021 were included.ResultsNineteen patients with various types of CHD were included. Median age was 58 (IQR 47–63) years. A total of 12/19 (63%) patients had had RF ablation of right atrial AT before. Median procedure duration was 225 (IQR 196–261) min. Median fluoroscopy time was 12.3 (IQR 5.2–19.5) min and median freeze time was 32 (IQR 28–36.3) min. Procedural success was achieved in all patients. Additional RF catheter ablation of intraatrial reentrant tachycardia within the left atrium was performed in 3/19 (16%) subjects and within the right atrium in 6/19 (32%) patients. Median follow-up was 26 (IQR 9–49) months. Excluding a 90-day blanking period, recurrence of AF was observed in 6/19 subjects (32%). After one redo procedure deploying RF energy only, 84% of all patients remained free from recurrence. Phrenic nerve palsy was observed in 1 subject.ConclusionResults after PVI using the cryoballoon plus additional RF ablation of AT were promising (84% success including one redo procedure). Success of AF ablation was unsatisfactory in all patients who had no additional AT ablation. Ablation of any AT in these patients should therefore be considered in addition to PVI.

P5361Pregnancy in patients with cardiac arrhythmias

Abstract Introduction Negative trends in the state of somatic and reproductive health of the female population are observed in the last decades all over the world. On the background of declining birth rates, the problems of managing pregnancy in women with extragenital pathology become relevant. Aim To study the effects of cardiac arrhythmias and antiarrhythmic treatment on the course and outcomes of pregnancy. Material and methods A total of 55 case histories of pregnant women hospitalized in the Department of Interventional Arrhythmology. All patients signed informed consent to be enrolled in the study. The age of patients ranged from 17 to 41 years (mean age of 30.2±4.0 years). Patients were hospitalized on average at 28.0±6.4 weeks of gestation (from 12 to 37 weeks) and had some form of cardiac arrhythmia. Results Cardiac arrhythmias were idiopathic in 65% of cases; the rest of patients had verified cardiovascular diseases. Cardiac arrhythmias were registered in 41 (74%) of women prior to pregnancy and their arrhythmological history lasted for 7.9±1.1 years. Extrasystolic arrhythmia was the most common type of cardiac arrhythmias: ventricular premature beats occurred in 23 pregnant women (42%) including supraventricular premature beats in 8 patients (14%), supraventricular tachycardia in 12 patients (22%), and ventricular tachycardia (VT) in 5 women (9%). In three cases, VTs were hemodynamically significant. Radiofrequency ablation (RFA) of VT was performed in pregnant women at 26, 27, and 32 weeks of gestation. Five patients with gestational ages of 27–34 weeks received RFA for atrial tachycardia and atrioventricular (AV) reciprocal tachycardia to treat symptomatic intracardiac tachycardia (n=4) and continuous recurrent AV nodal tachycardia (n=1), paroxysms of which were accompanied by destabilization of hemodynamics. AV block was registered in 4 pregnant women (9%); sick sinus syndrome was diagnosed in 1 patient (2%). Implantation of pacemaker was required in 1 case for a second-degree AV block type II (Mobitz type II) at 24 weeks of pregnancy. RFA and pacemaker implantation were carried out with minimal or zero fluoroscopy and only after the 22nd week of pregnancy, that is, without or with reduced radiation risk to the fetus. 16 patients (29%) had cesarean section; the rest of patients had spontaneous vaginal delivery. The average Apgar scores were 8.64 immediately after birth and 9.35 five minutes after birth. Preterm births (n=2) were due to obstetric pathology and were not associated with cardiac arrhythmias. Cardiac arrhythmias were not observed in any patient in childbirth. Conclusions Cardiac arrhythmias, observed in patients, did not require termination of pregnancy. Catheter ablation for symptomatic, hemodynamically significant, and life-threatening cardiac arrhythmias made it possible to effectively guide pregnant women to delivery with a close follow-up.

Радиочастотная аблация предсердной тахикардии у пациента с левой верхней полой веной

Радиочастотная аблация предсердной тахикардии у пациента с левой верхней полой веной

P317The usefulness of radiofrequency ablation of atrial tachycardias in young patients with significant paroxysmal atrial fibrillation

P317The usefulness of radiofrequency ablation of atrial tachycardias in young patients with significant paroxysmal atrial fibrillation

Focal atrial tachycardia originating from the septal mitral annulus: electrocardiographic and electrophysiological characteristics and radiofrequency ablation.

This study sought to investigate electrocardiographic characteristics, electrophysiological features, and radiofrequency ablation in patients with focal atrial tachycardia (AT) originating from the septal mitral annulus. In 13 patients with AT originating from the septal mitral annulus, activation mapping was performed to identify the earliest activation site. Successful ablation was performed through either a transseptal (n = 12) or a retrograde aortic approach (n = 1). As confirmed by electrogram recordings, fluoroscopy, and three-dimensional (3D) mapping, successful ablation sites were located in the anterior paraseptal, mid- to anteroseptal, and posterior septal mitral annulus in eight, three, and two patients, respectively. Foci for all locations demonstrated a negative/positive appearance in lead V1. Mapping in the right atrium demonstrated that the earliest right atrial activation was near the septum (His-bundle region or proximal coronary sinus). The electrograms at the successful ablation sites were fractionated in 9 patients, and presented with an atrial:ventricular ratio of <1 in all 13 patients. There were no complications in any patients and long-term success was achieved in 12 of 13 patients during the 23 ± 6 months following ablation. The area surrounding the septal mitral annulus, most commonly the anterior paraseptal, is an unusual, but important site of origin for focal AT, which is associated with a distinctive P-wave morphology and atrial endocardial activation sequence. Radiofrequency ablation of AT originating from the septal mitral annulus, through either a transseptal or a retrograde aortic approach appears to be safe and effective.

Radiofrequency ablation of atrial tachycardia from ''no-man's land"

Tachycardias originating from the peri-atrioventricular nodal region are rare, and can be challenging to ablate owing to the potential risk of atrioventricular block.

Radiofrequency Ablation for Atrial Tachycardia and Atrial Flutter

Atrial tachycardia is a generic term for a range of tachyarrhythmias with their origin in the atria. These can be broadly divided by mechanism into macro-reentrant, focal and small circuit re-entry. "Atrial flutter" is a term which, today, should be restricted to those classical circuits around the tricuspid annulus dependent on the cavo-tricuspid isthmus. The advent of sophisticated mapping solutions has rendered the vast majority of these atrial circuits curable with catheter ablation, with high success rates and very low incidence of complications.

Electrophysiologic characteristics and radiofrequency ablation of focal atrial tachycardia arising from non-coronary sinuses of Valsalva in the aorta

Focal atrial tachycardia (AT) arising from non-coronary cusp (NCC) is very rare, and the experience in catheter ablation of this kind of tachycardia remains limited. This study describes the electrophysiologic characteristics and radiofrequency ablation of AT arising from NCC. The study population consisted of five consecutive patients (three females and two males; age 37-68 years) with AT arising from NCC. The morphology of P waves was described as positive, negative, isoelectric, or biphasic (positive-negative or negative-positive). The atrial mapping was performed during tachycardia to define the earliest atrial activation site. Mean tachycardia cycle length of AT in five patients was 363 +/- 44 ms. P-wave morphology was predominantly upright or biphasic in lead II, III, and aVF, inverted in aVR. Positive P-wave morphology was seen in lead aVL in all five patients. The precordial leads were negative-positive in V(1) and V(2), negative-positive or positive in lead V(3)-V(5), and positive in lead V(6). All the five patients underwent successful radiofrequency ablation within NCC. During a follow up of > 3 months, no patient presented with a recurrence. This study demonstrated that mapping and ablation of focal AT arising from NCC is safe and effective. When earliest activation was recorded in the proximal electrode of the His-bundle catheter, but radiofrequency ablation in this region cannot successfully eliminated the tachycardia, the AT should be considered to arise from NCC especially when P-wave morphology was initially negative with a late positive component in right precordial leads, upright or biphasic in inferior leads.

Successful radiofrequency ablation of atrial tachycardias in surgically repaired Ebsteinʼs anomaly using the Carto XP system and the QwikStar catheter

We describe the case of a child with three different atrial tachyarrhythmias originating from the right atrium, in whom a limited modified maze procedure was performed during surgical repair of an Ebstein's anomaly. Successful radiofrequency transcatheter ablation of all atrial tachyarrhythmias, one re-entrant and two focal, was obtained using the Carto XP EP three-dimensional navigation and ablation system, the new QwikMap software technology and the new mapping/ablation QwikStar multipolar catheter. No conventional mapping was used in addition to the three-dimensional system. Total procedural time was about 3 h and fluoroscopy time was 40 min. There were neither recurrences of the tachycardias nor complications during the follow-up (15 months).

Radiofrequency ablation of atrial tachycardia in patients with repaired atrial septal defect

Objective To evaluate the electrophysiological characteristics and radiofrequency catheter ablation of atrial tachycardia (AT) in patients with repaired atrial septal defects (ASD). Methods In 76 consecutive patients with AT who underwent the electrophysiological study and radiofrequency catheter ablation (RFCA). 4 patients (one male and three female aged 35.5 ± 11.5 years) had AT-related myocardial scar or incision. Earliest activation combined with entrainment mapping was adopted to determine a critical isthmus. Results Re-entry related to the lateral atriotomy scar was inducible in 3 of 4 patients. With entrainment mapping, the PPI-TCL difference was <30 ms when pacing at the inferior margins of the right lateral atriotomy scar. Among them, 2 patients had successful linear ablation between scar area to inferior vena cava, and 1 patient between scar areas to tricuspid annulus. Re-entry involving an ASD patch was demonstrated in 1 of 4 patients. PPI-TCL differences <30 ms were found when entraining tachycardia at sites near the septal patch. But linear ablation failed in terminating AT. There was no complication during procedure. No recurrence of incision-related AT was found during follow-up except for the failed patient. Conclusion Under conventional electrophysiological mapping, adopting linear ablation from scar area to anatomic barrier, successful ablation also can be obtained in patients with IRAT related to myocardial scar or incision.

Adenosine-sensitive atrial tachycardia originating from the proximal coronary sinus

Atrial tachycardia (AT) can originate from the proximal coronary sinus (CS). However, detailed electrophysiologic characteristics of the tachycardia are not available. We describe the electrophysiologic characteristics, response to adenosine 5'-triphosphate, and results of radiofrequency ablation of AT with the earliest activation in the proximal CS. In 7 of 54 patients (age 57 +/- 18 years) with nonmacroreentrant "focal" AT undergoing electrophysiologic study and radiofrequency ablation, the earliest atrial activation site was located in the proximal CS. The earliest activation site was inside the CS 13 +/- 3 mm from the ostium. The AT could be induced and terminated by atrial extrastimuli or burst pacing. In all patients, the AT was also terminated by a very small dose of adenosine 5'-triphosphate (4.2 +/- 1.1 mg). Rapid ventricular pacing during the tachycardia produced ventriculoatrial dissociation. Radiofrequency ablation directed at the earliest atrial activation site was effective in only three patients (group A). In the remaining four patients (group B), after the radiofrequency energy deliveries, the earliest activation site shifted to an adjacent site with a small increase in the cycle length. Three group B patients underwent successful ablation in the slow pathway region. No recurrence was observed over a follow-up period of 22 +/- 5 months. AT with earliest activation in the proximal CS is sensitive to a small dose of adenosine 5'-triphosphate. In some patients, radiofrequency applications in the slow pathway region are effective even if the local activation is not early.

Radiofrequency ablation of atrial tachycardia and atrial flutter

Atrial endocardial mapping defines the activation pattern during regular atrial arrhythmias. The response to pacing (entrainment mapping) yields additional information about the mechanism and location of the circuit. Regarding radiofrequency ablation, the regular atrial tachycardias may be classified in two broad patterns: 1) macroreentrant tachycardias, characterized by circular activation, including typical atrial flutter and reentry around scars, and 2) focal tachycardias, characterized by radial activation from a small myocardial area. Catheter ablation of right atrial macroreentrant circuits and focal tachycardias are now standard procedures. The target for ablation of focal tachycardia is the point of earliest activation, and single application is effective in most cases. Ablation of macroreentrant tachycardias requires identifying a narrow isthmus inside the circuit, and linear ablation is needed in most cases. The goal of radiofrequency ablation for typical atrial flutter is to interrupt conduction across the inferior vena cavatricuspid valve isthmus. The procedure is highly effective and safe, although recurrences of the arrhythmia are not rare. Incisional macroreentrant tachycardias after surgical correction of congenital heart diseases and primary cardiac tumors may also be ablated identifying critical isthmuses in the circuit by a combination of mapping and entrainment techniques. Left atrial macroreentry is much less known and at present more information is needed before catheter ablation becomes a standard procedure.

Radiofrequency catheter ablation of atrial tachycardias

Atrial tachycardias are frequently unresponsive to medical therapy. His bundle ablation has been proposed as a palliative treatment to treat symptoms and prevent development of tachycardia-mediated cardiomyopathy. Experience with catheter ablation directed at the atrial origin of the tachycardia remains limited. We reviewed the initial success rate and long-term follow-up of radiofrequency ablation of atrial tachycardias. Thirty-six patients underwent electrophysiologic study and radiofrequency ablation of atrial tachycardias, excluding atrial flutter. The suspected mechanism of the clinical arrhythmia was automatic in 16 patients, intraatrial reentrant in 15, sinoatrial reentrant in 3, and unknown in 2. One or two ablation catheters with a 4 mm distal electrode were used to find (1) the earliest local atrial activation time compared to P-wave onset in the bipolar recording mode and (2) a QS pattern in the unipolar mode. When two ablation catheters were used, an encircling approach was taken. Pace-mapping during sinus rhythm and entrainment techniques were occasionally used for mapping. Tachycardia rose from the right atrium in 33 of 36 patients and from the left atrium in the remaining three. Three patients showed multiple foci during the procedure. Successful ablation was obtained in 31 (86%) of 36 patients, with a median of two radiofrequency applications (range 1 to 32) at 10 to 50 W for 10 to 60 seconds. Failure occurred in 5 patients (including the 3 patients with multiple atrial foci). Late follow-up (18 ± 15 months) showed recurrence of atrial tachycardia in 2 patients, each of whom underwent a successful second ablation. Emergence of another atrial tachycardia was noted in 2 other patients, and an uncommon atrial flutter was noted in 1 patient with repaired atrial septal defect. No late sinus or atrioventricular nodal dysfunction were observed. In conclusion, radiofrequency catheter ablation is a safe and reasonable alternative for atrial tachycardias that do not respond to drugs. However, as previously suggested by the surgical experience, the success rate of ablation appears less satisfactory in patients with multiple sites of origin of ectopic atrial tachycardia.