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.

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

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.

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.

Left-septal ablation of the fast pathway in AV nodal reentrant tachycardia refractory to right septal ablation

In more than 95% of patients with atrioventricular nodal reentrant tachycardia (AVNRT), curative treatment can be achieved with selective ablation of the slow pathway in the right-sided septum. We report a patient with typical AVNRT who had failed attempts to perform conventional right septal ablation of the slow as well as of the fast pathway and finally underwent successful ablation of the fast pathway on the left side of the interatrial septum using a transseptal approach.

Radiofrequency ablation of accessory pathways

INTRODUCTION

17 years ago the first radiofrequency catheter ablation of an accessory pathway (AP) was performed. The aim of this study was to describe the contemporary success rates and procedure related complication rates of radiofrequency (RF) ablation of accessory pathways (APs). In addition, the present study describes the anatomical distribution of APs according to the new nomenclature introduced by NASPE and ESC in 1999.

METHODS

The analysis included all patients, who underwent RF ablation of an AP in the Heart Center Leipzig between January 2000 and December 2003.

RESULTS

Over a 4 year period 336 APs were ablated in 323 patients. 201 APs (60%) presented with antegrade and retrograde conduction and showed preexcitation on ECG. For the remaining 135 APs (40%), only retrograde conduction over the AP was documented. According to the new nomenclature APs were classified as left-sided, right sided, septal and paraseptal APs. 188 APs (56%) were located on the left, 41 (12%) on the right, 64 (19%) in the paraseptal space and 31 APs (9%) presented with a septal or parahisian localization, respectively. Because of atypical course and/or characteristics 12 APs (4%) could not be classified. Ablation of all pathways were successful in 315 patients (98%). In 289 patients (89%) success was achieved within a single ablation session. The left-sided pathways had a re-intervention rate of 5%, which was significantly lower compared to the remaining localizations. The highest re-intervention rate was observed in the septal APs (23%). Complications were observed in less than 2% of all treated patients.

CONCLUSIONS

17 years after the first RF catheter ablation of an AP this therapy is established as a highly effective procedure. The success rate has improved to 98% and the complication rate has been minimized to less than 2%. The most frequent localization of APs is left posterior. Left sided APs also presented with the lowest re-intervention rate. The introduction of the new nomenclature in 1999 by NASPE and ESC has simplified the description of the exact anatomical localization of an AP.

Outflow tract tachycardia with R/S transition in lead V3

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.

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.

[Electrophysiological study: procedure and indications]

The purpose of an electrophysiological study is to verify the mechanism of arrhythmias and to decide the means of therapy for the clinical arrhythmia (pharmacological, radiofrequency catheter ablation, pacemaker-, ICD-implantation). The electrode catheters are introduced percutaneously into the right atrium, to the His-bundle, into the coronary sinus and/or into the right ventricle. By this electrode catheters the intracardiac electrograms are registered and programmed stimulation of the heart is performed. The electrical conduction properties are analysed. With stimulation manoeuvres most of the clinical tachycardias can be induced. In the first part of this overview we describe the procedure of an electrophysiological study, in the second part the indications are discussed.

Idiopathic enlargement of the right atrium: 23 year follow up of a familial cluster and their unaffected relatives

OBJECTIVE

To evaluate the long term outcome of familial idiopathic enlargement of the right atrium (IERA) and the risk of developing this disorder among unaffected offspring.

DESIGN

23 year follow up study.

PATIENTS

14 members (eight men, mean age 54 years, range 40-78) of a pedigree with familial IERA.

METHODS

All patients were examined clinically and echocardiographically in 1979 and 2002. Normal cross sectional dimensions of the right atrium were derived from echocardiographic evaluation of 100 people (47% men) with no structural or haemodynamic signs of heart disease. The 90th centile was chosen as the upper normal limit. IERA was defined as an increased right atrial long axis indexed to body surface area (RALAX(i), men > 2.6 cm/m2, women > 2.8 cm/m2) in the absence of other cardiac abnormalities. Severe IERA was defined arbitrarily as RALAX(i) > or = 4 cm/m2.

RESULTS

The course of the two index patients with severe IERA diagnosed in 1979 was complicated by atrial fibrillation, systemic embolism, and symptoms of heart failure without systolic dysfunction, resulting in the death of one man (77 years old). One of two patients with initially mild forms progressed to severe IERA. All of the initially unaffected offspring (n = 9) remained asymptomatic, although four of them had developed mild IERA.

CONCLUSIONS

During 23 years' follow up, severe IERA induced atrial fibrillation, systemic embolism, and symptoms of heart failure without systolic dysfunction in all cases in this family. Mild IERA seems to become manifest during middle age and may be followed by gradual progression to clinically relevant disease.

Stable Secondary Arrhythmias Late After Intraoperative Radiofrequency Ablation of Atrial Fibrillation:

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

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.

Coronary artery bypass grafts: ECG-gated multi-detector row CT angiography--influence of image reconstruction interval on graft visibility

PURPOSE

To evaluate the influence of different reconstruction intervals of retrospectively electrocardiographically (ECG)-gated multi-detector row computed tomographic (CT) angiography on image quality of different segments of various types of coronary artery bypass grafts.

MATERIALS AND METHODS

Twenty consecutive patients with 62 grafts underwent retrospectively ECG-gated four-channel multi-detector row CT angiography and conventional coronary angiography. Raw helical CT data were reconstructed at 0%-90% of the cardiac cycle in increments of 10%. Each graft was separated into three segments (proximal segment, graft body, and distal anastomosis). Three graft types were identified according to site of distal anastomosis. Two readers assessed image quality of segments and graft types. Effective radiation dose was calculated.

RESULTS

Best image quality of all segments was obtained at a reconstruction interval of 50%-70% of the cardiac cycle. Image quality of the proximal segment did not vary significantly with different reconstruction intervals (analysis of variance, P =.8), whereas image quality of the graft body and distal anastomosis changed significantly with varying reconstruction intervals (P <.001). Distal anastomosis and body of types 1 and 2 grafts were best seen at 60%-70% of the cardiac cycle, whereas distal anastomosis and body of type 3 grafts were best visualized at 50%. Accuracy of CT angiography for detection of graft patency was 94% for reader 1 and 95% for reader 2. Effective dose for CT was 11.4 mSv for both men and women. Mean effective dose for angiography was 2.1 mSv for men and women.

CONCLUSION

Optimal selection of reconstruction interval improves image quality of the graft body and of distal anastomosis in particular.

Vorhofflimmern – Update 2004

Vorhofflimmern ist die häufigste anhaltende Herzrhythmusstörung, wobei die Prävalenz mit zunehmendem Alter ansteigt. Obwohl Vorhofflimmern häufig mit einer strukturellen Herzerkrankung vergesellschaftet ist, tritt es bei vielen Patienten auch ohne erkennbare zugrunde liegende Herzerkrankung auf. Hämodynamische Beeinträchtigung und thromboembolische Ereignisse führen zu einer bedeutenden Morbidität, Mortalität und auch zu relevanten Gesundheitskosten. In dieser Übersichtsarbeit wird das zeitgemäße Management von Vorhofflimmern besprochen.

Kathetertechnische Behandlung von Vorhofflattern und Vorhofflimmern

In den letzen 20 Jahren haben verfeinerte elektrophysiologische Mappingtechniken zu einem besseren Verständnis der pathophysiologischen Grundlagen von Vorhofflattern und Vorhofflimmern geführt, was wiederum zur Entwicklung von kathetertechnischen Behandlungsverfahren mittels Hochfrequenzstromablation geführt hat. Bei rezidivierendem symptomatischem oder hämodynamisch relevantem typischem Vorhofflattern hat sich diese Behandlungsform als kurative Therapie der ersten Wahl im klinischen Alltag durchgesetzt. Auch bei Vorhofflimmern stellt die primäre Katheterablation eine neue, potentiell kurative Behandlungsoption dar. Dieses in klinischer Erprobung befindliche Verfahren muss sich jedoch aufgrund der zur Zeit noch nicht bekannten Langzeitergebnisse im Rahmen von kontrollierten Studien zuerst etablieren, bevor es bei Patienten mit Vorhofflimmern zu einem generellen Einsatz empfohlen werden kann. Bei Patienten mit Vorhofflimmern, die medikamentös nicht ausreichend behandelbar sind und die für die neuen Behandlungsverfahren mittels direkter Katheterablation nicht in Betracht kommen, kann als ultima ratio nach einer Schrittmacherimplantation der AV-Knoten zur Erzeugung eines kompletten AV-Blocks abladiert werden.

Aberrant tendinous chords with tethering of the tricuspid leaflets: a congenital anomaly causing severe tricuspid regurgitation

OBJECTIVE

To define the entity of tricuspid regurgitation caused by tethering of the tricuspid valve leaflets by aberrant tendinous chords.

DESIGN

Retrospective study.

SETTING

Tertiary care centre (university teaching hospital).

PATIENTS

10 patients with unexplained severe tricuspid regurgitation.

METHODS

The last 13 500 echocardiographic studies from our facility were reviewed to identify patients with severe unexplained tricuspid regurgitation. Tethering was defined by the presence of aberrant tendinous chords to the tricuspid valve leaflets limiting the mobility of the tricuspid leaflet and resulting in incomplete coaptation and apical displacement of the regurgitant jet origin. Aberrant tendinous chords were defined as those inserting at the clear zone of the tricuspid leaflet and not originating from the papillary muscle. Patients fulfilling the diagnostic criteria for Ebstein's anomaly were excluded.

RESULTS

10 patients with aberrant tendinous chords tethering one or more tricuspid valve leaflets were identified. There were short non-aberrant tendinous chords in seven patients, five of whom also had right ventricular or tricuspid annulus dilatation.

CONCLUSIONS

Tethering of the tricuspid valve leaflets by aberrant tendinous chords can be the sole mechanism of congenital tricuspid regurgitation. It is often associated with short non-aberrant tendinous chords, which may develop secondary to right ventricular or tricuspid annulus dilatation. Awareness of tethering as a cause of tricuspid regurgitation may be important in planning reconstructive surgery.

Electroanatomic Mapping of the Endocardium

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.

Enlargement of the right atrium--diverticulum or aneurysm?

Diverticula and aneurysms are rare congenital anomalies of the right atrium. Here, we report a case of a giant congenital diverticulum of the right atrium in a 27-year-old female and discuss the morphological characteristics distinguishing diverticula and aneurysms.