VT Recurrence After Ablation: Incomplete Ablation or Disease Progression? A Multicentric European Study.

AIM: To determine whether ventricular tachycardia (VT) recurrences in arrhythmogenic RV cardiomyopathy (ARVC) and nonischemic cardiomyopathy (NICM) are related to incomplete ablation or disease progression. METHODS: ARVC and NICM patients with two substrate maps of the same diseased ventricle with an interprocedural delay of ≥12 months were included. Disease progression was defined as ≥1 factor: scar area progression (PROG, +5%), ventricular remodeling (dilatation [+25 mL] or decreased ejection fraction [-5%EF]). Incomplete ablation was defined as index VT recurrence or ablation in previously unablated regions inside index scar without PROG. RESULTS: Twenty patients from nine centers were included (80% male 55 ± 16 years, 7 ARVC and 13 NICM, LVEF 43 ± 14%). Mean delay was 28 ± 18 months. Disease progression occurred in 75% with ventricular remodeling in 70%: ventricular dilation in 45% (ARVC [71%]; NICM [38%]), decreased EF in 60% [RVEF in ARVC (71%); LVEF in NICM (54%)], and scar progression in 50% (in ARVC [57%] and NICM [46%]). Index VT recurrence was observed in 40%. Redo ablation sites were located in previously unablated regions inside the index scar in 70% of patients. VT recurrence following the second procedure was seen in 25%. Fifteen percent died during a follow-up of 17 ± 17 months. CONCLUSION: Disease progression is the rule in ARVC and NICM while scar progression occurs in half. However, even if disease progression is frequently observed, incomplete index ablation is the most common finding, strongly suggesting the need for more extensive ablation.

Efficacy of TachoSil® as a sutureless hemostatic patch to repair a perforation of the interventricular groove during endocardial radiofrequency ablation.

Catheter ablation is a well-established therapeutic option for management of recurrent ventricular tachycardia in patients with ischemic/non-ischemic heart disease and procedural complications include a mortality rate of up to 3% and a risk of major complications up to 10%. Cardiac perforation following a catheter ablation is rare but serious complication and occurs in 1% of ventricular ablation procedures. The appropriate surgical repair may be challenging and need cardiopulmonary bypass support according to the location of the lesion and the hemodynamic status of the patient. We report the case of a free wall right ventricular perforation of the interventricular groove with cardiac tamponade following catheter ablation for recurrent ventricular tachycardia. Due to the proximity of the left anterior descending artery and the extreme fragility of tissues, the patient was treated successfully by a sutureless patch technique using a fibrin tissue-adhesive collagen fleece (TachoSil®). This technique is a safe and effective surgical option to repair a ventricular perforation especially when the ventricular tissues are fragile. It is simple and enable to realize surgical repair also if the localization of tear is difficult to access and without the need for cardiopulmonary bypass support if hemodynamic conditions are stable.

Sex-related differences in peri- and post-ablation clinical data for patients with atrial flutter.

UNLABELLED: Sex-related differences were not reported for the atrial flutter (AF). The purpose of the study was to look for the influence of gender on indications, clinical data and long-term results of AFl ablation. METHODS: 985 patients, [227 females (23%)] were referred for radiofrequency AFl ablation. Clinical history, echocardiography were collected. Patients were followed from 3 months to 10 years. RESULTS: Age of women and men was similar (65.5 ± 12 vs 64 ± 11.5 years). Underlying heart disease (HD) was as frequent in women as men (77.5 vs 77%), but women had more congenital HD (10 vs 2%;p<0.001), valvular HD (18 vs 10%;p<0.002), hypertensive HD (24 vs 18%;p<0.05), and less chronic lung disease (5 vs 10%;p<0.01), and ischemic HD (5 vs 20%;p<0.001). Atrial fibrillation (AF) history was more frequent in women (36 vs 27%;p<0.001). AFl-related tachycardiomyopathy (4.5 vs 8%;p<0.03) was more frequent, but 1/1 AFl (10 vs 6%;p=NS) as frequent. Failure of ablation (16 vs 10%;p<0.01), ablation-related major complications (3.5 vs 0.9%;p<0.005) were more frequent in women. After 3 ± 3 years, AFl recurrences were as frequent in women and men (10 vs 14%), AF occurrence more frequent in women (34 vs 19.5%; p<0.001). After excluding patients with previous AF, AF risk remained higher in women (19 vs 12%; p<0.004). CONCLUSIONS: In patients admitted for ablation, AFL was less common in women than in men, despite similar age and similarly prevalent HD. More than men, women had frequent AF history, a higher risk of failure of ablation and AFl ablation-related major complications and a higher risk of AF after ablation.

Correlations between the surface ECG and the intracavitary electrocardiogram in typical atrial flutter.

UNLABELLED: Typical atrial flutter (cavo-tricuspid isthmus-dependent) has as an electrophysiological substrate a macro-reentry circuit localized in the right atrium. Depending on the right atrial depolarization sequence, the rotation of the macro-reentry circuit can be counterclockwise (with an inferior to superior activation of the right atrium free wall and superior to inferior activation of the interatrial septum), characterized by negative F waves in inferior leads (DII, DIII, aVF) and V6, and positive in V1 on the surface electrogram (ECG), or clockwise (with a superior to inferior activation of the right atrium free wall and inferior to superior activation of the interatrial septum) characterized by positive F waves in inferior leads (DII, DIII, aVF) and V6, and negative in V1. Nevertheless, it is considered that for the diagnosis of the typical or atypical nature of this arrhythmia, the surface ECG has limited value. The purpose of this study was to compare the relationship between the flutter rotation sequence determined by the intracavitary electrogram and the morphology of the F waves on the surface ECG. METHODS: The study included 387 patients admitted to the Cardiology - Rehabilitation Hospital from Cluj-Napoca between January 2007 and May 2010, diagnosed with typical atrial flutter during an electrophysiological study. Using the intracavitary electrograms the flutter rotation sequence was determined (clockwise or counterclockwise). The F waves' aspect on the surface ECG in leads DII, DIII, aVF, aVL, V1 and V6 was then analyzed. RESULTS: One hundred and fifty two patients (39.3%) were diagnosed with clockwise atrial flutter and 235 patients (60.7%) with counterclockwise atrial flutter. The positive predictive value (PPV) of negative F waves in inferior leads and positive in V1 was, in the case of counterclockwise atrial flutter 98%; the negative predictive value (NPV) was 79%; sensitivity (Se) was 83% and specificity (Sp) was 97%. For typical clockwise atrial flutter, the PPV of the positive F waves in the inferior leads and negative in V1 was 94% (p < 0.001); the NPV was 85%; Se was 73% and Sp was 97%. CONCLUSION: The surface ECG has a high value in determining the macroreentry circuit rotation sequence in the case of typical atrial flutter.

What is the origin of this arrhythmia?

PURPOSE: The existence of inter-atrial epicardial connections bridging the two atria at different levels has well been described and their implication in some forms of supraventricular arrhythmias is a known fact. However, up to date, little data exists in the literature showing their role in the mechanisms of focal atrial tachycardias, providing at the same time clear electroanatomical and activation maps using a three-dimensional, non-fluoroscopic mapping system. PATIENTS AND METHODS: We present the case of a 29-year-old woman with a focal atrial tachycardia with the origin in a pulmonary vein, manifested as a right atrial origin due to the conduction of the electrical impulse form the right inferior pulmonary vein (RIPV) to the postero-inferior right atrium (RA) via inter-atrial epicardial connections. Using a three-dimensional, non-fluoroscopic mapping system (CARTO, Biosense Webster), an RA activation map was created during tachycardia. RESULTS: Radiofrequency (RF) application at the earliest endocardial breakthrough site situated in the postero-inferior RA changed the right atrial depolarization sequence without terminating the arrhythmia. Subsequently, a left atrium activation map was created showing the earliest endocardial breakthrough site at the level of the RIPV ostium and RF application at this level abolished the atrial tachycardia. CONCLUSION: Inter-atrial epicardial connections can be part of the substrate of some forms of supraventricular arrhythmias. Awareness of their existence is important to the electrophysiologist, since a better understanding of transseptal activation can avoid, in some cases, unnecessary RF applications at the level of the postero-septal right atrium, with a subsequent increase in procedural risk.

Assessment of the correlation between two defining criteria for bidirectional isthmic block in the ablation of typical atrial flutter.

BACKGROUND: A complete, bidirectional conduction block in the cavotricuspid isthmus (CTI) represents the end-point of the typical atrial flutter ablation. We investigated the correlation between two criteria for successful ablation, one based on the atrial bipolar electrogram morphology before and after complete CTI conduction block, compared to the standard criteria of differential pacing and reversal in the right atrial depolarization sequence during coronary sinus (CS) pacing. METHOD: We conducted a retrospective study in 111 patients (81 males, average age 62±10 years) who underwent an atrial flutter ablation during September 2007 - July 2009 in the Cardiology - Rehabilitation Hospital, UMF Cluj-Napoca. We assessed the presence of a bidirectional block at the end of the procedure using the standard criteria. We then analyzed the morphology of the bipolar atrial electrograms adjacent to the ablation line, before and after CTI conduction block. RESULTS: A change from a qRs morphology to a rSr' morphology when pacing from the coronary sinus and from a rsr' morphology to a QRS morphology when pacing from the low-lateral right atrium was associated with a CTI conduction block. Sensitivity (Se), specificity(Sp), positive predictive value (PPV), negative predictive value (NPV) were 96%, 89%, 99% and 67% respectively. CONCLUSION: Our study suggests that the analysis of the atrial bipolar electrogram next to the ablation line before and after CTI ablation may be used as a reliable criterion to validate CTI conduction block due to its high sensitivity, specificity and positive predictive value.

The role of radiofrequency ablation as a first line therapy in the treatment of atrial flutter.

UNLABELLED: Cavo-tricuspid isthmus radiofrequency (RF) ablation is an efficient option in the treatment of atrial flutter. In the case of a well-tolerated, first episode of atrial flutter, it has a class II indication, level of evidence B, the current first-line therapeutic option being electrical cardioversion, pharmacological cardioversion or atrial overdrive pacing followed by long-term antiarrhythmic therapy. The purpose of this study was to evaluate, in a prospective manner, the recurrence rate of these two different therapeutic options after the treatment of a first episode of atrial flutter. MATERIAL AND METHODS: Between January 2007 and May 2009, for 99 patients admitted to the hospital for a first episode of atrial flutter, cardioversion was attempted either by RF ablation (group 1-42 patients), or by electrical cardioversion, pharmacological cardioversion or atrial overdrive pacing followed by long-term Amiodarone therapy (group 21-57 patients). We compared the recurrence rate of atrial flutter in the 2 groups after a follow-up period of one year. RESULTS: In group 1, sinus rhythm was achieved in all patients, with bidirectional isthmic block being obtained for 37 patients (88.1%). In group 2, conversion to sinus rhythm was obtained in all cases. The recurrence rate was 6 times higher in group 2 vs group 1 (57.9% = 33 patients vs 9.5% = 4 patients) (p = 0.01). CONCLUSION: RF ablation should be considered as a therapeutic option in the treatment of the first episode of atrial flutter, due to its significant efficiency in maintaining sinus rhythm and to its low recurrence rate.

[Ablation of atrial fibrillation: new technologies and challenges]. / Ablation de la fibrillation atriale: enjeux du futur, progrès technologiques.

In industrialized countries, the number of atrial fibrillation (AF) catheter ablation procedures regularly increases every year, but these interventions are still time consuming and complex, especially for chronic AF. The stakes in the future are twofold : to reduce the duration of each ablation procedure and to increase the success rate for the more difficult AF ablation cases (i.e. : chronic AF), but with the lowest possible complications rate. Some technological improvements may contribute to reach these goals. Intracardiac 3D mapping and navigation systems as well as robotic-assisted catheter manipulation are available and these technologies are regularly upgraded. These systems are helpful both in catheter manoeuvring and repositioning as well as in the understanding of arrhythmia circuits and the definition ablation targets. In addition, these systems are equipped with software specially designed for automatic electrogram analysis to identify myocardial areas which may play a role in the maintenance of chronic AF. Cardiac imaging, such as MRI, may also help identifying arrhythmogenic areas in patients with chronic AF, with subsequent MRI 3D images integrated into a 3D mapping / navigation system. Several companies have invested on the research and development of ablation catheters aiming both at the reduction of procedure time as well as the improvement of the quality of the created lesions, especially with 'smart'catheters which can appreciate wall contact quality. Whatever the type of catheter shape or type of energy used, technological improvement is needed before the expected efficacy is reached.

Supraventricular tachyarrhythmia as a cause of sudden cardiac arrest.

INTRODUCTION: Supraventricular tachyarrhythmias (SVTA) are an accepted cause of cardiac arrest in patients with Wolff-Parkinson-White syndrome (WPW) and hypertrophic cardiomyopathy but their participation in other conditions is less well understood. The purpose of the study was to examine the role of SVTA in sudden cardiac arrest (SCA) by comprehensive evaluation of patients successfully resuscitated from SCA. METHODS: A total of 169 survivors of SCA in the absence of acute myocardial infarction underwent systematic evaluation that included echocardiography, Holter monitoring, coronary angiography and electrophysiological study (EPS) with additional testing in selected cases using provocative drug testing with isoproterenol, ajmaline or ergonovine. RESULTS: SVTA was found as the only possible cause or as the cause facilitating SCA in 29 patients: (1) 3 had a WPW syndrome related to accessory pathway with short refractory period; (2) for 12 patients, SVTA was the cause of cardiovascular collapse; heart disease (HD) was present in 11 cases, but disappeared in two of four with dilated cardiomyopathy after the restoration of sinus rhythm; (3) in 14 patients, SVTA degenerated either in a VF or ventricular tachycardia (VT); HD was present in 12 cases, but disappeared in one; two had no HD and recurrent similar arrhythmia was documented by cardiac defibrillator in one of them. SVTA induced coronary ischemia was the main cause of SCA. CONCLUSION: Rapid SVTA was a cause of SCA, either by cardiovascular collapse or by the degeneration in VT or VF. The complication generally occurred in patients with advanced HD or with rapid SVTA-induced cardiomyopathy and rarely in patients without HD. The incidence of SVTA as the only cause or the facilitating cause of SCAs is probably underestimated, because it is difficult to prove.

[New systems of mapping and navigation in electrophysiology]. / Nouveaux systèmes de cartographie et de navigation en électrophysiologie.

The indications of radiofrequency ablation of arrhythmias have considerably increased since the introduction of the technique in the early 1990s. Interventional rhythmologists now treat arrhythmias which are more and more complex by their mechanism. This requires accurate representation of the ablation catheter position and the integration of spatial and temporal data to identify the arrhythmogenic substrate. The systems of mapping and navigation developed over the last ten years are important tools for interventional rhythmologists. They are very useful for the identification of complex arrhythmogenic substrates which require "individualised" ablations in specific cases. The aim of this article is to review different systems of mapping, and/or navigation currently on the market and their principal characteristics without entering into the details of their use in interventional electrophysiology.

[Does syncope change the results of programmed ventricular stimulation in patients with previous myocardial infarction?]. / La syncope change-t-elle les résultats de la stimulation ventriculaire programmée chez les patients ayant un antécédent d'infarctus du myocarde?

UNLABELLED: The induction of a ventricular tachycardia (VT) after myocardial infarction (MI) is associated with a high risk of VT and sudden death (SD) in asymptomatic patients; the purpose of the study was to know if syncope modifies the results of programmed ventricular stimulation (PVS) and the clinical consequences. METHODS: PVS using two and three extra stimuli delivered in two sites of right ventricle was performed in 1057 patients without spontaneous VT or resuscitated SD at least 1 month after an acute MI; 836 patients (group I) were asymptomatic and were studied for a low ejection fraction or nonsustained VT on Holter monitoring or late potentials; 228 patients (group II) were studied for unexplained syncope. The patients were followed up to 5 years of heart transplantation. RESULTS: Sustained monomorphic VT (< 280 b/min) was induced in 238 group I patients (28%) and 62 group II patients (29%); ventricular flutter (VT > 270 b/min) or ventricular fibrillation (VF) was induced in 245 group I patients (29%) and 42 group II patients (18%) (P < 0.05); PVS was negative in 353 group I patients (42%) and 124 (55%) group II patients (NS). The patients differ by their prognosis; cardiac mortality was 13% in group I patients and 34% in group II patients with inducible VT < 280 b/min (P < 0.01), 4% in group I patients and 13% in group II patients with inducible VF (P < 0.05), 5% in group I patients and 7% in group II patients with negative study (NS). In conclusion, syncope did not change the results of programmed ventricular stimulation after myocardial infarction. However, syncope increased significantly cardiac mortality of patients with inducible ventricular tachycardia, flutter or fibrillation.

[The electrocardiogram in ventricular tachycardias]. / Electrocardiogramme des tachycardies ventriculaires.

The electrocardiogram, as much as the clinical examination, is a basic tool for the cardiologist. Technological advances have led to a certain lack of interest in learning to read the electrocardiogram, for which close analysis can allow precise diagnosis, notably in the field of cardiac rhythm disorders. This article concerns the electrocardiogram in ventricular tachycardias with two themes: differential diagnosis of wide QRS complex tachycardias and recognition of the site of origin of a ventricular tachycardia. "Fine" analysis of the electrocardiogram is not an intellectual "game". Actually, careful analysis of the 12 lead ECG allows exact and rapid diagnosis in a large majority of cases, distinguishing a ventricular tachycardia from a supraventricular tachycardia with conduction defect; the appropriate management can be selected without delay. At the same time, close reading of the electrocardiogram also allows the site of origin of a ventricular tachycardia to be recognised. Combining this information with elements of the patient's record can allow the arrhythmia to be related to a known pathology or to prompt a targeted aetiological investigation.

[Risk factors for cardiac mortality in cases of syncope with previous history of myocardial infarction]. / Facteurs de risque de mortalité cardiaque en cas de syncope et d'antécédents d'infarctus du myocarde.

Syncope is considered to be a clinical sign predictive of sudden death in patients with a previous history of myocardial infarction. The aim of this study was to determine the prognostic factors in this population. The study population included 228 patients with myocardial infarction over one month old and who had no documented ventricular tachycardia. The patients were referred for investigation of syncope. The left ventricular ejection fraction (LVEF) was measured by echocardiography or radionucleide technique. Complete electrophysiological study including programmed atrial and ventricular stimulation was performed in all cases. The patients were followed up for 6 months to 5 years or until cardiac transplantation (average 3+/-1 years). One hundred and nineteen patients had a LVEF <40% (Group I) and 109 patients had a LVEF >40% (Group II). Sustained monomorphic ventricular tachycardia (VT) with a rate inferior to 280/min was induced in 44 patients in Group I (37%) and in 18 patients in Group II (16.5%), p<0.05. Ventricular flutter or fibrillation was induced in 24 patients in Group I (19%) and in 19 patients in Group II (17%) (NS). Different causes of syncope (conduction disturbances, supraventricular tachycardia, increased vagal tone, severe coronary ischaemia) were found in 23 patients in Group I (19%) and 32 patients in Group II (29%) (NS). Syncope was unexplained in 43 patients in Group I (36%) and 40 patients in Group II (37%) (NS). The prognosis was very different. In Group I, the cardiac mortality was 49% in patients with inducible monomorphic VT <280/min, 35% in those with inducible ventricular flutter or fibrillation but only 9% in patients without inducible ventricular arrhythmias. In Group II, the prognosis was independent of the results of programmed stimulation and much better: cardiac mortality was 5.5% in patients with inducible VT, 5% in those with inducible ventricular flutter or fibrillation and 4% in patients without inducible ventricular arrhyhtmias. The authors conclude that LVEF is the most powerful predictor of cardiac mortality and sudden death in cases of syncope with a past history of myocardial infarction. The prognosis also depends on the results of programmed ventricular stimulation when the LVEF is inferior to 40%. Sustained monomorphic VT is the most frequently induced arrhythmia in this case and the prognosis of these patients is particularly poor. On the other hand, syncope does not appear to be a poor prognostic factor in the group with normal LVEF, even when it is possible to induce VT.

Correlation between electrogram morphology and standard criteria to validate bidirectional cavotricuspid block in common atrial flutter ablation.

AIM: Assessment of a bidirectional conduction block within the cavotricuspid isthmus (CTI) is critical during radiofrequency (RF) atrial flutter (AF) ablation. We investigated the use of bipolar atrial electrogram (BAE) morphology as an additional criterion identifying CTI block and tested it against two recognized criteria: differential pacing and reversal of the right atrial depolarization sequence during coronary sinus (CS) pacing. METHODS AND RESULTS: An RF ablation procedure was performed during 600 ms CS pacing in 100 consecutive patients with a common AF. BAE recorded along the CTI were continuously monitored. CTI conduction block was achieved by RF ablation in all patients and a clear change in BAE polarity in the Electrogram recorded by the dipoles located on the CTI and immediately lateral to the intended line of block (RS to QR pattern) associated with a confirmed CTI conduction block was observed in all cases. BAE morphology changes predicted bidirectional CTI conduction blocks with a 100% positive and a 100% negative predictive value. At a mean follow-up of 33 +/- 11 months, there was a 5% AF recurrence rate. CONCLUSIONS: Our study suggests that morphological changes in BAE recorded at sites lateral and adjacent to the target line of block may be used as a unique and robust criterion to validate CTI conduction block during AF ablation procedure.

Acute resumption of conduction in the cavotricuspid isthmus after catheter ablation in patients with common atrial flutter. Real-time evaluation and long-term follow-up.

AIMS: Cavotricuspid isthmus conduction (CIC) is closely associated with the maintenance and recurrence of common atrial flutter (AFL). This study systematically sought to assess the prevalence and characteristics of acute CIC recovery during AFL ablation and to define its predictors and its relationship with the results of long-term follow-up. METHODS AND RESULTS: A total of 124 consecutive patients (105 men, 19 women, mean age 58 +/- 11 years) who underwent successful AFL ablation were included. The procedure endpoint was defined as complete bi-directional CIC block. During an observation period of 30 min, the incidence of CIC restoration was 34.% in patients and 39.8% in applications. It increased with increasing block time and decreased over time during the observation period. Block time in successful burns followed by persistent block was shorter than in those followed by CIC resumption (12 +/- 6 vs 33 +/- 12 s, P<0.0001). A negative correlation between block time and resumption time was found (r = - 0.57, P<0.001). Patients with permanent pacemakers had a higher incidence of acute CIC resumption than those without pacemakers (5/7 vs 29/117, P = 0.007). The AFL recurrence rate was 4.8% during a mean follow-up period of 21 +/- 8 months. Our results suggest that acute CIC resumption may be a potential risk for clinical AFL recurrence during long-term follow-up. CONCLUSIONS: Acute CIC resumption in common AFL ablation varies in terms of incidence and time course. Block time has a predictive value for acute CIC recovery. Observation time can be shortened if block time is short. With longer block time, it is essential to observe for a longer period in order to minimize CIC resumption.

[Immediate and long-term results of radiofrequency ablation of accessory atrioventricular pathways]. / Résultats immédiats et à long terme de l'ablation par radiofréquence des faisceaux accessoires atrioventriculaires. Rôle de la maturation de la technique.

The aim of this study was to report the authors' experience of radiofrequency ablation of accessory atrioventricular pathways over a 10 year period (01-91 to 10-00), and the effect of the "learning curve" on the results. The data of 400 patients admitted to primo-ablation of a bundle of Kent was analysed retrospectively. A total of 481 ablations were performed (1.20 per patient). The cumulative global success in the 414 accessory pathways treated was 90.6%. The primary success rate increased from the 1st to the 4th quartile from 68 to 97% (p = 0.0001). The mean duration of fluoroscopy and number of ablation sites decreased from the 1st to the 4th quartile respectively from 47 +/- 27 to 25 +/- 18 minutes (p = 0.0001) and from 8.5 +/- 7.8 to 4.5 +/- 3.8 minutes (p = 0.0001). The average recurrence rate over the four quartiles was 3.6. The overall complication rate was 1.44%. The improved primary success rate from 1991 to 2000 and, in parallel, the reduction of the number of inappropriate ablation sites and fluoroscopy duration are explained not only by the "learning curve" of our centre but also by the benefits of the application of scientific acquisitions (unipolar recordings, criteria for ablation site localisation...) and technical progress (ablation with temperature monitoring...) over this period.