Yan Huo

Comparison of CHADS2, R2CHADS2 and CHA2DS2-VASc Scores for the Prediction of Rhythm Outcomes after Catheter Ablation of Atrial Fibrillation: The Leipzig Heart Center AF Ablation Registry

Background—Recurrences of atrial fibrillation (AF) occur in up to 30% within 1 year after catheter ablation. This study evaluated the value of CHADS2, R2CHADS2, and CHA2DS2-VASc scores for the prediction of rhythm outcomes after AF catheter ablation. Methods and Results—Using the Leipzig Heart Center AF Ablation Registry, we documented rhythm outcomes within the first 12 months in 2069 patients (67% men; 60±10 years; 35% persistent AF) undergoing AF catheter ablation. AF recurrences were defined as any atrial arrhythmia occurring within the first week (early recurrences, ERAF) and between 3 and 12 months (late recurrences, LRAF) after ablation. ERAF and LRAF occurred in 36% and 33%, respectively. On multivariable analysis, R2CHADS2 (odds ratio [OR], 1.11; 95% confidence interval [CI], 1.02–1.21; P=0.016) and CHA2DS2-VASc (OR, 1.09; 95% CI, 1.017–1.17; P=0.015) scores as well as persistent AF and left atrial diameter were significant predictors for ERAF. Similarly, the same clinical variables remained significant predictors for LRAF even after adjustment for ERAF, which was the strongest predictor for LRAF (HR, 3.12; 95% CI, 2.62–3.71; P<0.001). However, using receiver operating characteristic curve analyses, both scores demonstrated relatively low predictive value for ERAF (area under the curve [AUC], 0.536 [0.510–0.563]; P=0.007; and AUC, 0.547 [0.521–0.573]; P<0.001 for R2CHADS2 and CHA2DS2-VASc, respectively) and LRAF (AUC, 0.548 [0.518–0.578]; P=0.002; and AUC, 0.550 [0.520–0.580]; P=0.001). Conclusions—R2CHADS2 and CHA2DS2-VASc were associated with rhythm outcomes after catheter ablation. However, AF type, left atrial diameter, and especially ERAF are also significant predictors for LRAF that should be included into new clinical scores for the prediction of rhythm outcomes after catheter ablation.

Catheter ablation of atrial fibrillation supported by novel nonfluoroscopic 4D navigation technology

BACKGROUND The MediGuide technology (MGT) represents a novel sensor-based electromagnetic 4-dimensional (4D) navigation system allowing real-time catheter tracking in the environment of prerecorded X-ray loops. OBJECTIVE To report on our clinical experience in atrial fibrillation (AF) ablation with recently available MGT-enabled ablation catheters. METHODS The MGT was used in addition to a conventional 3D mapping system in 80 patients with AF (age 61 ± 10 years; 47 men; 40 with persistent AF), who underwent circumferential pulmonary vein isolation and voltage mapping with and without substrate modification. Short native right anterior oblique/left anterior oblique loops were used as background movies for the nonfluoroscopic placement of sensor-equipped diagnostic catheters into the coronary sinus and the right ventricle. After single transseptal puncture, selective angiograms of the pulmonary veins were used as background movies for near nonfluoroscopic left atrial reconstruction. Computed tomography registration as well as mapping/ablation was performed by using the new open-irrigated MGT-enabled ablation catheter. RESULTS MGT application was not associated with a change in established workflow. Large parts of the procedure (mean entire duration 167 ± 47 minutes) could be done without additional fluoroscopy, whereas median residual fluoroscopy duration of 4.6 (interquartile range: 2.9, 7.1) minutes was mainly used for the acquisition of background loops, transseptal puncture, occasional verification of transseptal sheath position, and manipulation of the circular mapping catheter. Three (4%) minor complications occurred. CONCLUSIONS The MGT integrates easily into the workflow of standard AF ablation and allows for high-quality nonfluoroscopic 4D catheter tracking. This results in low radiation exposure for patients and staff without complicating the workflow of the procedure.

Nonfluoroscopic Catheter Visualization in Atrial Fibrillation Ablation Experience From 375 Consecutive Procedures

Background—A technological platform (MediGuide) has been recently introduced for nonfluoroscopic catheter tracking. No data on the safety of this technology are yet available in a large cohort of patients. Methods and Results—Data from a prospective ablation registry were analyzed. All patients undergoing atrial fibrillation ablation procedures supported by nonfluoroscopic catheter visualization technology were included. Patient characteristics and procedural data and complications within the first 3 months were recorded. Between May 2012 and February 2014, a total of 375 patients underwent atrial fibrillation ablation using nonfluoroscopic catheter visualization technology. The patients were predominantly men (68%); the majority were ablated for the first time (71%); left atrium was 43±6 mm; and left ventricular function was normal (59±9%). The median ablation procedure time was 135 (113–170) minutes, median fluoroscopy time 2.8 (1.5–4.4) minutes, and median radiation dose 789 (470–1466) cGy*cm2. Regression analysis demonstrated a significant decrease of fluoroscopy time, dose, and procedure time. To confirm the result and show overall changes, the initial 50 cases (group 1) to the last 50 cases (group 2) of the series were compared: fluoroscopy time decreased from 6.0 (4.1–10.3) minutes in group 1 to 1.1 (0.7–1.5) minutes in group 2 and radiation dose from 2363 (1413–3475) to 490 (230–654) cGy*cm2, respectively. Ten patients (2.7%) experienced complications: 5 cardiac tamponades (1.4%), 4 pseudoaneurysms (1.1%), and 1 stroke (0.3%). Conclusions—Atrial fibrillation ablation using the nonfluoroscopic catheter visualization technology is safe with a rate of complications of 2.7%. Procedure time (135 minutes) is not prolonged. A dramatic reduction in fluoroscopy time and dose was achieved.Background— A technological platform (MediGuide) has been recently introduced for nonfluoroscopic catheter tracking. No data on the safety of this technology are yet available in a large cohort of patients. Methods and Results— Data from a prospective ablation registry were analyzed. All patients undergoing atrial fibrillation ablation procedures supported by nonfluoroscopic catheter visualization technology were included. Patient characteristics and procedural data and complications within the first 3 months were recorded. Between May 2012 and February 2014, a total of 375 patients underwent atrial fibrillation ablation using nonfluoroscopic catheter visualization technology. The patients were predominantly men (68%); the majority were ablated for the first time (71%); left atrium was 43±6 mm; and left ventricular function was normal (59±9%). The median ablation procedure time was 135 (113–170) minutes, median fluoroscopy time 2.8 (1.5–4.4) minutes, and median radiation dose 789 (470–1466) cGy*cm2. Regression analysis demonstrated a significant decrease of fluoroscopy time, dose, and procedure time. To confirm the result and show overall changes, the initial 50 cases (group 1) to the last 50 cases (group 2) of the series were compared: fluoroscopy time decreased from 6.0 (4.1–10.3) minutes in group 1 to 1.1 (0.7–1.5) minutes in group 2 and radiation dose from 2363 (1413–3475) to 490 (230–654) cGy*cm2, respectively. Ten patients (2.7%) experienced complications: 5 cardiac tamponades (1.4%), 4 pseudoaneurysms (1.1%), and 1 stroke (0.3%). Conclusions— Atrial fibrillation ablation using the nonfluoroscopic catheter visualization technology is safe with a rate of complications of 2.7%. Procedure time (135 minutes) is not prolonged. A dramatic reduction in fluoroscopy time and dose was achieved.

Cavotricuspid Isthmus Ablation Guided by Real-Time Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) has evolved as a standard cardiac imaging technique. Interventional procedures guided by real-time MRI may derive potential benefit from a fluoroscopy-free working environment, more detailed insights into the target anatomy, and additional information on organ tissue properties relevant for pathomorphology as well as therapy delivery. Electrophysiological (EP) procedures in a magnetic resonance (MR) scanner require new workflows with different, MR safe, interventional materials and hardware setup, different approaches to intracardiac orientation and catheter tracking, and an adapted patient management. Recently, invasive diagnostic EP procedures have been described in animal studies and in a clinical setting.1,2 Actual catheter ablation has so far only been reported in a limited number of animal series.3 Hereby, we report on a MRI-guided cavotricuspid isthmus ablation. A 74-year-old man without structural heart disease was admitted with documented episodes of paroxysmal symptomatic typical right atrial flutter. At the ablation procedure the patient presented in sinus rhythm. The patient was enrolled into a clinical study approved by the local ethics committee and by the German Federal Institute for Drugs and Medical Devices (BfArM). He provided written and verbal informed consent. In this study, we used MR conditional catheters (Vision, Imricor Medical Systems, Burnsville, MN) and an MR conditional EP recording system (Bridge MR EP Recording System, Imricor Medical Systems, Burnsville, MN). The material is designed for use in 1.5 T closed bore scanners and imposes no limitations on the catheter trajectory, scanner landmark, or patient position. The catheter allows for all clinical scan protocols and is safe for use in normal and first level controlled operating modes. ### MR Conditional Catheters Although the appearance and functionality are similar to conventional ablation catheters, the design of the MR conditional catheter differs substantially. All ferromagnetic materials are removed to eliminate the potential for force and torque …

Effect of Limb Lead Electrodes Location on ECG and Localization of Idiopathic Outflow Tract Tachycardia: A Prospective Study

Role of ECG in Localization of OT‐VT. Background: Different kinds of the surface ECG limb electrode positions may affect the limb lead vector and therefore the accuracy of the 12‐lead ECG in localization of outflow tract ventricular tachycardia (OTVT). This study was intended to evaluate and compare the accuracy of the standard and the modified 12‐lead ECG for localization of OTVT using the current published criteria.

Non-Fluoroscopic Catheter Visualization in AF Ablation: Experience from 375 Consecutive Procedures

Background—A technological platform (MediGuide) has been recently introduced for nonfluoroscopic catheter tracking. No data on the safety of this technology are yet available in a large cohort of patients. Methods and Results—Data from a prospective ablation registry were analyzed. All patients undergoing atrial fibrillation ablation procedures supported by nonfluoroscopic catheter visualization technology were included. Patient characteristics and procedural data and complications within the first 3 months were recorded. Between May 2012 and February 2014, a total of 375 patients underwent atrial fibrillation ablation using nonfluoroscopic catheter visualization technology. The patients were predominantly men (68%); the majority were ablated for the first time (71%); left atrium was 43±6 mm; and left ventricular function was normal (59±9%). The median ablation procedure time was 135 (113–170) minutes, median fluoroscopy time 2.8 (1.5–4.4) minutes, and median radiation dose 789 (470–1466) cGy*cm2. Regression analysis demonstrated a significant decrease of fluoroscopy time, dose, and procedure time. To confirm the result and show overall changes, the initial 50 cases (group 1) to the last 50 cases (group 2) of the series were compared: fluoroscopy time decreased from 6.0 (4.1–10.3) minutes in group 1 to 1.1 (0.7–1.5) minutes in group 2 and radiation dose from 2363 (1413–3475) to 490 (230–654) cGy*cm2, respectively. Ten patients (2.7%) experienced complications: 5 cardiac tamponades (1.4%), 4 pseudoaneurysms (1.1%), and 1 stroke (0.3%). Conclusions—Atrial fibrillation ablation using the nonfluoroscopic catheter visualization technology is safe with a rate of complications of 2.7%. Procedure time (135 minutes) is not prolonged. A dramatic reduction in fluoroscopy time and dose was achieved.Background— A technological platform (MediGuide) has been recently introduced for nonfluoroscopic catheter tracking. No data on the safety of this technology are yet available in a large cohort of patients. Methods and Results— Data from a prospective ablation registry were analyzed. All patients undergoing atrial fibrillation ablation procedures supported by nonfluoroscopic catheter visualization technology were included. Patient characteristics and procedural data and complications within the first 3 months were recorded. Between May 2012 and February 2014, a total of 375 patients underwent atrial fibrillation ablation using nonfluoroscopic catheter visualization technology. The patients were predominantly men (68%); the majority were ablated for the first time (71%); left atrium was 43±6 mm; and left ventricular function was normal (59±9%). The median ablation procedure time was 135 (113–170) minutes, median fluoroscopy time 2.8 (1.5–4.4) minutes, and median radiation dose 789 (470–1466) cGy*cm2. Regression analysis demonstrated a significant decrease of fluoroscopy time, dose, and procedure time. To confirm the result and show overall changes, the initial 50 cases (group 1) to the last 50 cases (group 2) of the series were compared: fluoroscopy time decreased from 6.0 (4.1–10.3) minutes in group 1 to 1.1 (0.7–1.5) minutes in group 2 and radiation dose from 2363 (1413–3475) to 490 (230–654) cGy*cm2, respectively. Ten patients (2.7%) experienced complications: 5 cardiac tamponades (1.4%), 4 pseudoaneurysms (1.1%), and 1 stroke (0.3%). Conclusions— Atrial fibrillation ablation using the nonfluoroscopic catheter visualization technology is safe with a rate of complications of 2.7%. Procedure time (135 minutes) is not prolonged. A dramatic reduction in fluoroscopy time and dose was achieved.

Epicardial Ventricular Tachycardia Ablation in a Patient With Brugada ECG Pattern and Mutation of PKP2 and DSP Genes

The Brugada syndrome (BS) and arrhythmogenic right ventricular cardiomyopathy (ARVC) are currently seen as 2 distinct clinical entities. However, several genetic mutations linked to reduced sodium transmembrane flow and disrupted integrity of the desmosome with resulting fatty infiltration have been identified, corresponding to BS and ARVC, respectively.1 A 22-year-old male patient was admitted to our hospital with repeated discharges of the implantable cardioverter defibrillator caused by pleomorphic ventricular tachycardia. He had a previous history of survived sudden cardiac death and an implanted single-chamber implantable cardioverter defibrillator in 2010. No data on work-up of genetic arrhythmias had been available to date. On current clinical presentation in echocardiography, normal ejection fraction and heart diameter could be determined. Because of abnormal ECG pattern in a sense of an incomplete right bundle branch block with slightly elevated ST-segments and T-wave inversions in the right precordial leads, an ajmaline test was conducted (Figure A). This resulted in prominent coved-type Brugada ECG (Figure B). Figure. A , Baseline …

Relevant ventricular septal defect caused by steam pop during ablation of premature ventricular contraction.

A 62-year-old female patient with highly symptomatic, idiopathic, monomorphic, premature ventricular contraction presented at our institution for further treatment (Figure 1A). Previous medical antiarrhythmic treatment has failed. She had a history of mitral valve repair attributable to rheumatic heart disease 2 years before and paroxysmal atrial fibrillation. Aside from that, transthoracic echocardiogram revealed no structural heart disease. Indication was set for catheter ablation. After transseptal puncture (BRK-0 transseptal needle, St. Jude Medical, St. Paul, MN) a left ventricular electroanatomic activation map of the premature ventricular contraction was done using the CARTO-3 RMT system (Biosense-Webster, Diamond Bar, CA). The site of earliest activation was found in an inferoseptal apical position (Figure 1B and 1C). During radiofrequency ablation at this site with a 3.5-F external irrigated tip …

Diagnosis of atrial tachycardias originating from the lower right atrium: importance of P-wave morphology in the precordial leads V3-V6.

AIMS This study aimed to characterize P-wave morphology (PWM) in leads V3-V6 during focal atrial tachycardia (AT) originating from the lower right atrium (RA), and to investigate the role of interatrial conduction (IAC) pathways in the formation of PWM. METHODS AND RESULTS Twenty-eight consecutive patients with tachycardia foci in the lower RA underwent detailed atrial endocardial activation mapping and radiofrequency catheter ablation. P-wave configuration was analysed using standard 12-lead electrocardiogram. Atrial tachycardia originated from lower non-septal tricuspid annulus (LTA) (n = 11), coronary sinus ostium (CSo) (n = 11), lower crista terminalis (LCT) (n = 4), or lower free wall (n = 2). In leads V3-V6, PWM showed a negative pattern in at least two consecutive leads during AT originating from CSo (11/11) and LTA (9/11), with an associated sensitivity of 91%, specificity of 100%, positive predictive value (PPV) of 100%, and negative predictive value (NPV) of 75%. A positive PWM was observed in three of four ATs originating from LCT, with an associated sensitivity of 75%, specificity of 100%, PPV of 60%, and NPV of 96%. A negative PWM in V3-V6 was consistent with a preferential IAC through musculature in the vicinity of the CS and an activation of both atria in an antero-posterior direction. In contrast, a positive PWM was associated with the engagement of a posterior (non-CS-related) interatrial connection. CONCLUSION Characteristic PWMs in V3-V6 may accurately differentiate the anatomic sites of AT from the low RA with high PPVs and NPVs. P-wave morphology in V3-V6 is likely to be influenced by the engagement of the preferential IAC.

Continuous monitoring after atrial fibrillation ablation: the LINQ AF study

Abstract Aims To study device performance, arrhythmia recurrence characteristics, and methods of outcome assessment using a novel implantable cardiac monitor (ICM) in patients undergoing ablation for atrial fibrillation (AF). Methods and results In 419 consecutive patients undergoing first-time catheter ablation for symptomatic paroxysmal (n = 224) or persistent (n = 195) AF an ICM was injected at the end of the procedure. Telemedicine staff ensured full episode transmission coverage and manually evaluated all automatic arrhythmia episodes. Device detection metrics were calculated for ≥2, ≥6, and ≥10 min AF detection durations. Four methods of outcome assessment were studied: continuous recurrence analysis, discontinuous recurrence analysis, AF-burden analysis, and analysis of individual rhythm profiles. A total of 43 673 automatic AF episodes were transmitted over a follow-up of 15 ± 6 months. Episode-based positive predictive values changed significantly with longer AF detection durations (70.5% for ≥2 min, 81.8% for ≥6 min, and 85.9% for ≥10 min). Patients with exclusive short episode recurrences (≥2 to <6 min) were rare and their arrhythmia detection was clinically irrelevant. Different methods of outcome assessment showed a large variation (46–79%) in ablation success. Individual rhythm characteristics and subclinical AF added to this inconsistency. Analysis of AF-burden and individual rhythm profiles were least influenced and showed successful treatment in 60–70% of the patients. Conclusion We suggest AF detection duration >6 min and AF burden >0.1% as a standardized outcome definition for AF studies to come in the future.