Digitalis therapy is associated with higher comorbidities and poorer prognosis in patients undergoing ablation of atrial arrhythmias: data from the German Ablation Registry.

BACKGROUND: Digitalis glycosides are employed for rate control of atrial fibrillation. Recent studies suggested potential harmful effects of digitalis monotherapy and combination with antiarrhythmic drugs. The aim of the present study was to assess the prevalence and potential impact of digitalis therapy on outcome in patients undergoing catheter ablation of supraventricular arrhythmias. METHODS AND RESULTS: The German Ablation Registry is a nationwide, prospective registry with a 1-year follow-up investigating 12,566 patients receiving catheter ablations of supraventricular arrhythmias in 52 German centres. The present analysis focussed on pharmacotherapy in 8608 patients undergoing catheter ablation of atrial tachycardia, atrial fibrillation, or atrial flutter. Patients receiving digitalis therapy (n = 417) were older and presented a significantly increased prevalence of comorbidities including coronary artery disease, heart failure, diabetes, and pulmonary disease. One-year mortality was significantly higher in digitalis-treated patients (4.7% vs. 1.3%, p < 0.001), most strikingly in patients undergoing ablation of atrial flutter. This effect was maintained after adjustment for important risk factors. Similar results were obtained for as the combined endpoint of death, myocardial infarction, stroke and major bleeding (6.6% vs. 2.7%, p < 0.001), and non-fatal rehospitalisations (54.1% vs. 45.1%, p = 0.001). CONCLUSION: In the present study of patients undergoing catheter ablation of supraventricular arrhythmias, an association of digitalis therapy with increased mortality and an increased rate of other severe adverse events were observed. The results from this 'real-life' registry are consistent with previously published studies. However, whether digitalis therapy promotes a poorer prognosis or may just serve as a marker for this aspect cannot be thoroughly interpreted.

Ablation of atrioventricular nodal reentrant tachycardia in the elderly: results from the German Ablation Registry.

BACKGROUND: Catheter ablation (CA) is considered the treatment of choice for patients with atrioventricular nodal reentrant tachycardia (AVNRT). However, there is a tendency to avoid CA in the elderly because of a presumed increased risk of periprocedural atrioventricular (AV) nodal block. OBJECTIVE: The purpose of this prospective registry was to assess age-related differences in the efficacy and safety of CA within a large population with AVNRT. METHODS: A total of 3,234 consecutive patients from 48 German trial centers who underwent CA of AVNRT between March 2007 and May 2010 were enrolled in this study. The cohort was divided into three age groups: <50 years (group 1, n = 1,268 [39.2%]; median age = 40 [30.0-45.0] years, 74.1% women), 50-75 years old (group 2, n = 1,707 [52.8%]; 63.0 [58.0-69.0] years, 63.0% women), and > 75 years old (group 3, n = 259 [8.0%]; 79.0 [77.0-82.0] years, 50.6% women). RESULTS: CA was performed with radiofrequency current (RFC) in 97.7% and cryoablation technology in 2.3% of all cases. No differences were observed among the three groups with regard to primary CA success rate (98.7% vs. 98.8 % vs. 98.5%; P = .92) and overall procedure duration (75.0 minutes [50.0-105.0]; P = .93). Hemodynamically stable pericardial effusion occurred in five group 2 (0.3%) and two group 3 (0.8%) patients but in none of the group 1 (P <.05) patients. Complete AV block requiring permanent pacemaker implantation occurred in two patients in group 1 (0.2%) and six patients in group 2 (0.4%) but none in group 3 (P = 0.41). During a median follow-up period of 511.5 days (396.0-771.0), AVNRT recurrence occurred in 5.7% of all patients. Patients >75 years (group 3) had a significantly longer hospital stay (3.0 days [2.0-5.0]) compared with group 1 (2.0 days [1.0-2.0]) or group 2 (2.0 days [1.0-3.0]) patients (P <.0001). CONCLUSION: CA of AVNRT is highly effective and safe and does not pose an increased risk for complete AV block in patients over 75 years of age, despite a higher prevalence of structural heart disease. Antiarrhythmic drug therapy is often ineffective in this age group; thus, CA for AVNRT should be considered the preferred treatment even in elderly patients.

Trigger activity more than three years after left atrial linear ablation without pulmonary vein isolation in patients with atrial fibrillation.

OBJECTIVES: The aim of this study was to analyze trigger activity in the long-term follow-up after left atrial (LA) linear ablation. BACKGROUND: Interventional strategies for curative treatment of atrial fibrillation (AF) are targeted at the triggers and/or the maintaining substrate. After substrate modification using nonisolating linear lesions, the activity of triggers is unknown. METHODS: With the LA linear lesion concept, 129 patients were treated using intraoperative ablation with minimal invasive surgical techniques. Contiguous radiofrequency energy-induced lesion lines involving the mitral annulus and the orifices of the pulmonary veins without isolation were placed under direct vision. RESULTS: After a mean follow-up of 3.6 +/- 0.4 years, atrial ectopy, atrial runs, and reoccurrence of AF episodes were analyzed by digital 7-day electrocardiograms in 30 patients. Atrial ectopy was present in all patients. Atrial runs were present in 25 of 30 patients (83%), with a median number of 9 runs per patient/week (range 1 to 321) and a median duration of 1.2 s/run (range 0.7 to 25), without a significant difference in atrial ectopy and atrial runs between patients with former paroxysmal (n = 17) or persistent AF (n = 13). Overall, 87% of all patients were completely free from AF without antiarrhythmic drugs. CONCLUSIONS: A detailed rhythm analysis late after specific LA linear lesion ablation shows that trigger activity remains relatively frequent but short and does not induce AF episodes in most patients. The long-term success rate of this concept is high in patients with paroxysmal or persistent AF.

Differentiating atrioventricular nodal reentrant tachycardia from tachycardia via concealed accessory pathway.

Studies analyzing the diagnostic value of 12-lead electrocardiographic criteria differentiating slow-fast atrioventricular nodal reentrant tachycardia (AVNRT) from atrioventricular reentrant tachycardia (AVRT) due to concealed accessory pathway have shown inconsistent results. In 97 patients (50 with AVNRT, 47 with AVRT) 12-lead electrocardiograms (ECGs) were recorded during sinus rhythm and tachycardia (QRS <120 ms). The ECGs were blinded for diagnosis and patient and analyzed independently by 2 electrophysiologists. The studied criteria differentiating AVNRT from AVRT included pseudo-r'/S, the presence of a retrograde P wave, RP interval, ST-segment depression >/=2 mm with the number and location of the affected leads, QRS amplitude, and cycle length alternans.

Outflow tract tachycardia with R/S transition in lead V3: six different anatomic approaches for successful ablation.

OBJECTIVES: The aim of this study was to analyze different anatomic mapping approaches for successful ablation of outflow tract tachycardia with R/S transition in lead V(3). BACKGROUND: Idiopathic ventricular tachycardia can originate from different areas in the outflow tract, including the right and left ventricular endocardium, the epicardium, the pulmonary artery, and the aortic sinus of Valsalva. Although electrocardiographic criteria may be helpful in predicting the area of origin, sometimes the focus is complex to determine, especially when QRS transition in precordial leads is in V(3). METHODS: We analyzed surface electrocardiograms of 33 successfully ablated patients with outflow tract tachycardia: 20 from the right ventricular outflow tract (RVOT) and 13 from different sites. The R/S transition was determined, and the different anatomic approaches needed for successful catheter ablation were studied. RESULTS: Overall, R/S transition in lead V(3) was present in 19 (58%) of all patients. In these patients, mapping was started and successfully completed in the RVOT in 11 of 19 (58%) patients. The remaining eight patients with R/S transition in lead V(3) needed five additional anatomic accesses for successful ablation: from the left ventricular outflow tract (n = 3), aortic sinus of Valsalva (n = 2), coronary sinus (n = 1), the epicardium via pericardial puncture (n = 1), and the trunk of the pulmonary artery (n = 1), respectively. CONCLUSIONS: A R/S transition in lead V(3) is common. In patients with outflow tract tachycardia with R/S transition in lead V(3), a stepwise endocardial and epicardial mapping through up to six anatomic approaches can lead to successful radiofrequency catheter ablation.

Paraseptal accessory pathway in Wolff-Parkinson- White-Syndrom: ablation from the right, from the left or within the coronary sinus/middle cardiac vein?

AIMS: In 1999 the consensus statement "living anatomy of the atrioventricular junctions" was published. With that new nomenclature the former posteroseptal accessory pathway (APs) are termed paraseptal APs. The aim of this study was to identify ECG features of manifest APs located in this complex paraseptal space. METHODS AND RESULTS: ECG characteristics of all patients who underwent radiofrequency ablation of an AP during a 3 year period were analyzed. Of the 239 patients with one or more APs, 30 patients had a paraseptal AP with preexcitation. Compared to APs within the coronary sinus (CS) or the middle cardiac vein (MCV) the right sided paraseptal APs significantly more often showed an isoelectric delta wave in lead II and/or a negative delta wave in aVR. The left sided paraseptal APs presented a negative delta wave in II significantly more often compared to the right sided APs. CONCLUSIONS: According to the site of radiofrequency ablation, paraseptal APs are classified into 4 subgroups: paraseptal right, paraseptal left, inside the CS or inside the MCV. Subtle differences in preexcitation patterns of the delta wave as well as of the QRS complex exist. However, the definitive localization of APs remains reserved to the periinterventional intracardiac electrogram analysis.

Topographic variability of the esophageal left atrial relation influencing ablation lines in patients with atrial fibrillation.

UNLABELLED: Topography of the esophagus in atrial fibrillation ablation. INTRODUCTION: The close anatomic relationship of the posterior wall of the left atrium (LA) and the thermosensitive esophagus creates a potential hazard in catheter ablation procedures. METHODS AND RESULTS: In 30 patients (pts) with atrial fibrillation (AF) undergoing catheter ablation, we prospectively studied the course and contact of the esophagus in relation to LA and the topographic proximity to ablation lines encircling the right-sided and left-sided pulmonary veins (PV) as well as to the posterior line connecting the encircling lines using the electromagnetic mapping system for reconstruction of LA and for tagging of the esophagus. This new technique of anatomic tagging of the esophagus was validated against the CT scan as a standard imaging procedure. The esophageal course was highly variable, extending from courses in direct vicinity to the left- or right-sided PV as well as in the midportion of the posterior LA. In order to avoid energy application in direct proximity to the esophagus, adjustments of the left and right PV encircling lines were necessary in 14/30 pts (47%) and 3/30 (10%). In 30 pts (100%), the mid- to inferior areas of the posterior LA revealed contact with the esophagus. Therefore, posterior and inferior linear ablation lines were abandoned and shifted to superior in 29 pts (97%). CONCLUSIONS: Anatomic tagging of esophagus revealed a highly variable proximity to different areas of the posterior LA suggesting individual adjustment of encircling and linear ablation lines in AF ablation procedures to avoid the life threatening complication of esophagus perforation.

Stable secondary arrhythmias late after intraoperative radiofrequency ablation of atrial fibrillation: incidence, mechanism, and treatment.

INTRODUCTION: Intraoperative radiofrequency (RF) ablation is an effective treatment of atrial fibrillation (AF). However, secondary arrhythmias late after ablation may complicate the patient's course. We report on the incidence, mechanisms, and treatment of gap-related atrial flutter and other secondary arrhythmias during long-term follow-up. METHODS AND RESULTS: In 129 patients who underwent intraoperative RF ablation with placement of left atrial linear lesions using minimally invasive surgical techniques, secondary arrhythmias were analyzed during long-term follow-up (20 +/- 6 months). Transient atrial arrhythmias during the first 3 postoperative months were excluded. In 8 (6.2%) of 129 patients, sustained stable secondary arrhythmias were documented. Left atrial, gap-related atrial flutter was observed in 4 patients (3.1%). The flutter was treated by percutaneous RF ablation in 3 patients (2.3%) and with drugs in 1 patient (0.8%). In 2 patients (1.6%), right atrial isthmus-dependent atrial flutter occurred and was treated successfully by percutaneous RF ablation. In 2 patients (1.6%), ectopic right atrial tachycardias occurred and were treated with percutaneous RF ablation. CONCLUSION: Late after intraoperative RF ablation of atrial fibrillation, three types of stable secondary arrhythmias were observed in 6% of patients: left atrial gap-related atrial flutter, right atrial isthmus-dependent atrial flutter, and ectopic atrial tachycardia. Gaps after intraoperative RF ablation due to noncontinuous or nontransmural linear lesions may lead to stable left atrial macroreentrant tachycardias, requiring new interventional therapy.

Time courses and quantitative analysis of atrial fibrillation episode number and duration after circular plus linear left atrial lesions: trigger elimination or substrate modification: early or delayed cure?

OBJECTIVES: We sought to analyze the time course of atrial fibrillation (AF) episodes before and after circular plus linear left atrial ablation and the percentage of patients with complete freedom from AF after ablation by using serial seven-day electrocardiograms (ECGs). BACKGROUND: The curative treatment of AF targets the pathophysiological corner stones of AF (i.e., the initiating triggers and/or the perpetuation of AF). The pathophysiological complexity of both may not result in an "all-or-nothing" response but may modify number and duration of AF episodes. METHODS: In patients with highly symptomatic AF, circular plus linear ablation lesions were placed around the left and right pulmonary veins, between the two circles, and from the left circle to the mitral annulus using the electroanatomic mapping system. Repetitive continuous 7-day ECGs administered before and after catheter ablation were used for rhythm follow-up. RESULTS: In 100 patients with paroxysmal (n = 80) and persistent (n = 20) AF, relative duration of time spent in AF significantly decreased over time (35 +/- 37% before ablation, 26 +/- 41% directly after ablation, and 10 +/- 22% after 12 months). Freedom from AF stepwise increased in patients with paroxysmal AF and after 12 months measured at 88% or 74% depending on whether 24-h ECG or 7-day ECG was used. Complete pulmonary vein isolation was demonstrated in <20% of the circular lesions. CONCLUSIONS: The results obtained in patients with AF treated with circular plus linear left atrial lesions strongly indicate that substrate modification is the main underlying pathophysiologic mechanism and that it results in a delayed cure instead of an immediate cure.

Late recurrent arrhythmias after ablation of atrial fibrillation: incidence, mechanisms, and treatment.

OBJECTIVES: The aim of the study was to determine the incidence of atrial flutter and other arrhythmia recurrences (other than atrial fibrillation [AF]) during long-term follow-up after left atrial substrate modification by percutaneous radiofrequency (RF) ablation of AF. BACKGROUND: RF ablation is an effective treatment for patients with AF. However, late recurrent arrhythmias may complicate the patient's course. METHODS: One hundred fifty consecutive patients with paroxysmal or persistent AF were included in this prospective study. The incidence of arrhythmia recurrences after AF ablation was analyzed during long-term follow-up using repetitive 7-day ECG recording. RESULTS: In 28 of 150 patients (18.7%), stable regular arrhythmias other than AF were detected during follow-up. Left atrial flutter observed in 10 patients (6.7%) was treated by recompletion of the ablation lines in all 10 patients. Left atrial flutter was associated with recurrence of AF in all 10 patients. Nine of 10 patients (90%) were free from atrial flutter and 6 of 10 patients were free from AF after the second intervention. Typical right atrial flutter occurred in 10 patients (6.7%) and was treated successfully by percutaneous RF ablation without recurrence in all patients. Additionally, atrial flutter was documented during follow-up in 7 patients (4.7%); however, invasive electrophysiologic evaluation was not performed due to various reasons. CONCLUSIONS: Left atrial flutter is a relevant complication after RF catheter ablation of AF and was always associated with AF recurrence in our study population. Prevention of left atrial flutter can be achieved by induction of ablation lines as continuous and transmural as possible. However, left atrial flutter that does occur late after ablation is amenable to interventional treatment with good prospects of success.

Electroanatomic mapping of the endocardium. Implication for catheter ablation of ventricular tachycardia.

The electroanatomic mapping system Carto((R)) with its combination of anatomic and electrophysiologic information has substantially improved our understanding of arrhythmia mechanisms and substrates in patients with ventricular tachycardia (VT) and structural heart disease. Identification of the individual arrhythmogenic substrate and successful ablation guided by the combination of sinus rhythm voltage mapping and conventional electrophysiologic techniques like pace and activation/entrainment mapping are best described for patients with recurrent VT in remote myocardial infarction. In about 75-90% of the patients, the target VT can be ablated with acute success and the patients remain free of any VT recurrence in up to 75%. First results of electroanatomically guided ablation in patients with arrhythmogenic right ventricular dysplasia are promising. Data on ablation of VT in other structural heart diseases are very limited, since the arrhythmogenic substrate is very diffuse, e. g., in dilated cardiomyopathy, or there are only small patient numbers, e. g., for cardiac sarcoidosis or monomorphic VT after repair of congenital heart disease. In this article, the current status of electroanatomically guided endocardial mapping and ablation of VT in patients with structural heart disease is described.

Catheter ablation of ventricular tachycardia in remote myocardial infarction: substrate description guiding placement of individual linear lesions targeting noninducibility.

INTRODUCTION: The aim of this study was to describe the arrhythmogenic substrate in postinfarction patients with ventricular tachycardia (VT) guiding the placement of individual strategic linear lesions transecting all potential isthmuses using target area maps with limited mapping points to allow short procedure times. METHODS AND RESULTS: In 28 patients with pleomorphic, unstable, and/or incessant VT, electroanatomic voltage mapping was performed in conjunction with limited sinus rhythm mapping, pace mapping, and activation mapping. Radiofrequency (RF) energy was applied directly within the low-voltage areas of the chronically infarcted areas or in the border zone. Ablation lines typically were perpendicular to the course of the presumed central common pathways. The maps consisted of 63 +/- 30 mapping points. An average lesion line length of 46 +/- 21 mm was placed with 17 +/- 7 RF pulses. Twenty-two (79%) of the 28 patients were rendered completely noninducible at the end of the procedure. Procedure time measured 134 +/- 41 minutes. No major complications were observed. Six (27%) of 22 patients who were rendered completely noninducible experienced VT recurrence during follow-up versus 4 (67%) of 6 patients who were still inducible after ablation (P = 0.06). CONCLUSION: Individually tailored substrate description guiding the placement of linear lesion lines transecting potential isthmuses rendered 80% of the patients completely noninducible. The construction of regional target area maps allowed short procedure times, with a resulting low incidence of complications in these critically ill patients.

Specific linear left atrial lesions in atrial fibrillation: intraoperative radiofrequency ablation using minimally invasive surgical techniques.

OBJECTIVES: A specific left atrial (LA) linear lesion concept for treatment of paroxysmal and permanent atrial fibrillation (AF) was tested using intraoperative ablation with minimally invasive surgical techniques. BACKGROUND: Curative treatment for patients with chronic AF is among the main challenges of interventional electrophysiology. METHODS: Seventy patients (mean age 53 +/- 10 years) with drug-refractory persistent (n = 28) or paroxysmal (n = 42) AF underwent intraoperative radiofrequency (RF) ablation using video-assisted minimally invasive techniques via a right anterolateral minithoracotomy. Contiguous lesion lines involving the mitral annulus and the orifices of the pulmonary veins were placed with RF energy application under direct vision to prevent anatomically defined LA re-entrant circuits. RESULTS: Mean follow-up was 18 +/- 7 months in patients with permanent AF and 18 +/- 5 months in patients with paroxysmal AF. Antiarrhythmic drug treatment was instituted in patients with postoperative atrial arrhythmias to allow "reverse electrical remodeling" and was discontinued after three months. Six months following ablation, 93% of the patients were in sinus rhythm in both groups, and after 12 months, 95% and 97%, respectively. As major complications, one esophagus perforation and one circumflex coronary artery stenosis were observed. CONCLUSIONS: A pure linear lesion line concept confined to the left atrium targeting specifically at elimination of anatomically defined LA "anchor" re-entrant circuits eliminated AF in >90% of the patients treated with intraoperative ablation using minimally invasive surgical techniques over a mean follow-up of 1.5 years.