Martin Martinek

Impact of Integration of Multislice Computed Tomography Imaging into Three-Dimensional Electroanatomic Mapping on Clinical Outcomes, Safety, and Efficacy Using Radiofrequency Ablation for Atrial Fibrillation

Background: Circumferential radiofrequency catheter ablation (RFCA) around the orifices of the pulmonary veins (PV) is a curative catheter‐based therapy of paroxysmal, persistent, and permanent atrial fibrillation (AF). Integration of multislice computed tomography into three‐dimensional electroanatomic mapping to guide catheter ablation has been shown to be accurate and feasible. This study investigated whether the use of such sophisticated imaging technology translates into better clinical outcomes, procedural efficacy, and safety in comparison with a control group treated with conventional three‐dimensional electroanatomic mapping.

Pulmonary vein stenosis by ostial irrigated-tip ablation: incidence, time course, and prediction.

Monitoring and Prediction of PV Stenosis. Introduction: The incidence of pulmonary vein (PV) stenosis and its time course for ostial trigger elimination in paroxysmal atrial fibrillation (PAF) is uncertain. In addition, the clinical value of serial computed tomographic (CT) scanning of the PV ostia and the predictive value of energy requirements for radiofrequency ablation have yet to be established.

Esophageal damage during radiofrequency ablation of atrial fibrillation: impact of energy settings, lesion sets, and esophageal visualization.

Introduction: Atrioesophageal fistula is an uncommon but often lethal complication of atrial fibrillation (AF) ablation. The purpose of our study was to prospectively investigate the incidence of esophageal ulcerations (ESUL) as well as the impact of energy settings, radiofrequency lesion sets, and direct visualization of the esophagus on esophageal wall injury.

Clinical impact of an open-irrigated radiofrequency catheter with direct force measurement on atrial fibrillation ablation.

Background: Electrode‐tissue contact is crucial for adequate lesion formation in radiofrequency catheter ablation (RFCA).

Identification of a high-risk population for esophageal injury during radiofrequency catheter ablation of atrial fibrillation: procedural and anatomical considerations.

BACKGROUND Atrioesophageal fistula is an uncommon but life-threatening complication of atrial fibrillation (AF) ablation. Esophageal ulcerations (ESUL) have been proposed to be potential precursor lesions. OBJECTIVE The purpose of our study was to prospectively investigate the incidence of ESUL in a large patient population undergoing radiofrequency catheter ablation (RFA). Additionally, we aimed to link demographic data and lesion sets with anatomical information given by multislice computed tomography imaging and to correlate these data with the development of ESUL. METHODS This study included 267 patients and consecutively screened all individuals for evidence of ESUL 24 h after RFA of AF by endoscopy of the esophagus. A standardized ablation approach using a 25-W energy maximum at the posterior left atrial (LA) wall without esophagus visualization, temperature monitoring, or intracardiac ultrasound was performed. RESULTS In total, we found 2.2% of patients (6 of 267) presenting with ESUL. Parameters exposing a specific patient to risk of developing ESUL in univariate analysis were persistent AF (5 of 95, P = .023), additional lines performed (roofline: 6 of 114, P = .006; LA isthmus: 4 of 49, P = .011; coronary sinus: 5 of 66, P = .004), and LA enlargement (P = .001) leading to sandwiching of the esophagus between the LA and thoracic spine. Multivariate analysis revealed LA-to-esophagus distance as the only significant risk factor. CONCLUSION This study is the first to link anatomical information and procedural considerations to the development of ESUL in radiofrequency ablation for AF. Furthermore, it reveals the correlation and individual impact of these factors. Not a single patient with pulmonary vein isolation alone developed ESUL.

New insights into long-term follow-up of atrial fibrillation ablation: full disclosure by an implantable pacemaker device.

Introduction: Long‐term outcome of radiofrequency ablation (RFA) for atrial fibrillation (AF) is difficult to assess. This study sought to evaluate various aspects of very long‐term follow‐up (FU) by the properties of an implantable device.

Asymptomatic cerebral lesions during pulmonary vein isolation under uninterrupted oral anticoagulation

AIMS Left atrial radiofrequency ablation has been shown to carry a risk of asymptomatic cerebral lesions. No data exist in patients under continued oral anticoagulation during the ablation procedure. The aim of this study was to quantify the amount of silent cerebral lesions assessed by pre-procedural and post-procedural magnetic resonance imaging (MRI) in patients under therapeutic international normalized ratio (INR) and to identify clinical or procedural parameters that correlate with cerebral embolism. METHODS AND RESULTS A total of 131 consecutive patients undergoing catheter ablation for paroxysmal (n = 80, 61.1%) or persistent (n = 51, 38.9%) atrial fibrillation were included in the study. Pulmonary vein antrum isolation (PVI), roofline, mitral isthmus line, and complex fractionated atrial electrogram (CFAE) ablation using 3.5 mm open-irrigated tip catheters were performed, as needed. All patients underwent pre-procedural and post-procedural cerebral MRI. Post-procedural MRI revealed new embolic lesions in 16 patients (12.2%), all of them asymptomatic. Clinical parameters showing a significant correlation with cerebral embolism in univariate analysis were age (P = 0.027), persistent atrial fibrillation (vs. paroxysmal; P = 0.039), and spontaneous echo contrast in transesophageal echocardiography (P = 0.029). Significant procedural parameters were electric cardioversion (P = 0.041), PVI only (P = 0.008), and ablation of complex atrial electrograms (P = 0.005). Independent risk factors in multivariate analysis were age (P = 0.009), spontaneous echo contrast (P = 0.029) and CFAE ablation (P = 0.006). CONCLUSION Radiofrequency ablation in patients under continued oral therapeutic anticoagulation is associated with a substantial risk of silent embolism detected by cerebral MRI. Therefore, continuation of oral anticoagulation is not able to prevent cerebral embolism. A variety of different clinical and procedural factors seem to contribute to the risk of cerebral lesions.

Acute development of gastroesophageal reflux after radiofrequency catheter ablation of atrial fibrillation

BACKGROUND Induction of gastroesophageal reflux after radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) may have an impact on the progression of esophageal injury. OBJECTIVE The purpose of this study was to assess the acute effect of RFCA on distal esophageal acidity using leadless pH-metry capsules. METHODS A total of 31 patients (27 male and 4 female; 25 with paroxysmal AF) who underwent RFCA and esophagoscopy 24 hours before and after ablation were assessed for reflux and esophageal lesions. A leadless pH-metry capsule was inserted into the lower esophagus to screen for pH changes, number and duration of refluxes, and the DeMeester score (a standardized measure of acidity and reflux). No patient had a history of reflux or was taking proton pump inhibitors within 4 weeks before and 24 hours after ablation. RESULTS Five patients (16.1%) who presented with asymptomatic reflux prior to ablation were excluded from further examination. Of the remaining 26 patients, 5 (19.2%) demonstrated a significant pathologic increase in DeMeester score after ablation. No statistical differences in baseline parameters, method of sedation, ablation approach, and total energy delivered on the posterior wall were observed between patients with and those without a pathologic DeMeester score. One patient with asymptomatic reflux prior to ablation developed esophageal ulceration. CONCLUSION A significant number of patients undergoing RFCA of AF develop pathologic acid reflux after ablation. In addition, a subgroup of patients has a preexisting condition of asymptomatic reflux prior to ablation. This finding may explain a potential mechanism for progression of esophageal injury to atrio-esophageal fistulas in patients undergoing RFCA.

QRS Characteristics Fail to Reliably Identify Ventricular Tachycardias That Require Epicardial Ablation in Ischemic Heart Disease

Criteria for Epicardial Origin in Ischemic VT. Objectives: We tested proposed algorithms for idiopathic and nonischemic tachycardias for their ability to identify epicardial LV‐VT origins.

Quantification of Atrial Tachyarrhythmia Burden with an Implantable Pacemaker Before and After Pulmonary Vein Isolation

Long‐term efficacy of pulmonary vein (PV) ostial isolation for paroxysmal atrial fibrillation is difficult to assess. We evaluated the net duration of atrial tachyarrhythmia episodes (burden), atrial tachyarrhythmia episode frequency, and quality‐of‐life (QOL) before and after PV isolation in patients with an existing pacemaker featuring extensive diagnostic capabilities. Due to frequent recurrences of paroxysmal atrial fibrillation, PV isolation was performed 21 ± 10 months following pacemaker implantation on 12 patients (57 ± 5 years) with normal left ventricular function. Atrial tachyarrhythmia burden (ATB) and episode frequency were monitored daily by the device both pre‐ and postablation. QOL questionnaires were collected at ablation and 1, 3, and 6 months thereafter. Patients were followed for 20 ± 9 and 11 ± 9 months pre‐ and postablation, respectively. Membrane‐active antiarrhythmic medications were discontinued after ablation in 8 of 12 patients. PV isolation resulted in a significant reduction of ATB from a median of 3.2 hours/day (preablation) to 0.2 hours/day (postablation, P < 0.01, Wilcoxon signed‐rank test). The median tachyarrhythmia frequency was 6.4 episodes/day (preablation) and 0.3 episodes/day (postablation, P = 0.09). QOL measures significantly improved over the data collection intervals (P < 0.05). Tachyarrhythmia burden was positively associated with Symptom Checklist frequency and severity (P < 0.01). Significant long‐term reductions in total ATB (symptomatic and asymptomatic) were observed. Furthermore, reductions in ATB were associated with improvements in QOL measures. Extensive monitoring capabilities in implantable devices help provide complete disclosure on the effect of PV isolation in paroxysmal atrial fibrillation patients.