Esophageal temperature monitoring during radiofrequency ablation of atrial fibrillation

INTRODUCTION: Ablative strategies for atrial fibrillation have centered on the left atrium, in particular the pulmonary veins. An emphasis on ablating outside the ostia of the pulmonary veins appears to have reduced the risk of pulmonary vein stenosis. Unfortunately, ablation in the posterior left atrium has been reported to result in fatal atrio-esophageal fistula. METHODS AND RESULTS: We monitored esophageal temperatures in 16 consecutive patients undergoing atrial fibrillation ablation. There were 14 men and 2 women; average age 54.7 +/- 10.6 years. Eight patients had a lasso-guided pulmonary isolation procedure, eight an electroanatomically guided left-atrial circumferential approach. A commercially available esophageal temperature probe (Mallinckrodt Mon-a-therm 12F Esophageal Stethoscope with Temperature Sensor, Thermistor 400 Series) was positioned under general anesthesia. Temperature changes were noted and related to the relative location of the ablation catheter and the temperature probe during the temperature change. The esophagus was midline in three, right sided in three, and left sided in the remaining patients. Temperature rises could be recorded at the posterior aspect of any pulmonary vein. Detailed analysis of six patient maps revealed heating occurred with lesions created within 1 cm of the esophagus. CONCLUSION: The location of the esophagus relative to the back of the left atrium displays considerable variability. It is rarely midline and most often lies in close proximity to the left-sided veins. Ablation in close radiographic proximity (approximately 1 cm) to the esophagus as defined by a radio-opaque temperature probe can result in heating at the esophageal lumen.     

Real-time monitoring of luminal esophageal temperature during left atrial radiofrequency catheter ablation for atrial fibrillation: observations about esophageal heating during ablation at the pulmonary vein ostia and posterior left atrium

INTRODUCTION: Left atrial radiofrequency catheter ablation (RFA) is gaining acceptance as treatment for drug-refractory atrial fibrillation (AF). This therapy has been associated with esophageal injury and atrioesophageal fistula formation causing death. METHODS: We describe 3 patients undergoing catheter ablation for AF during real-time monitoring of luminal esophageal temperature. RESULTS: We observed heating of the esophagus during short duration low power RFA, at either the left or right pulmonary vein ostia. Cryoablation at the pulmonary vein ostium in one patient resulted in esophageal cooling. Furthermore, we observed that fluoroscopic localization of the ablation catheter at a site apparently distant from the esophagus is not adequate to assure avoidance of ablation-induced esophageal heating. CONCLUSIONS: Real-time monitoring of luminal esophageal position and temperature is feasible, enhances recognition of esophageal heating, and may add useful information beyond that provided by fluoroscopic assessment of esophageal position. There is a potential role for esophageal monitoring to help avoid thermal injury to the esophagus during catheter ablation for atrial fibrillation.     

Temporal stability of the location of the esophagus in patients undergoing a repeat left atrial ablation procedure for atrial fibrillation or flutter

Background: The esophagus may be mobile during a left atrial (LA) ablation procedure for atrial fibrillation (AF).
Objective: The goal of the study was to determine whether the location of the esophagus is stable in patients undergoing a repeat LA ablation procedure.
Methods: Forty-two patients underwent repeat LA ablation a mean of 7 ± 2 months after the initial procedure. Cinefluoroscopic images of the esophagus during a barium swallow were recorded and the course of the esophagus was tagged on the 3D map. The position of the esophagus at the index and repeat procedure were compared.
Results: At the index procedure, the esophagus was located near the left pulmonary veins (PVs) in 20 (48%), right PVs in 13 (31%), and at the mid LA in 9 (21%) patients. During the repeat procedure, the esophagus was found to be near the left PVs in 22 (52%), right PVs in 11 (26%), and at the mid LA in 9 patients (21%). In 35 of the 42 patients (83%), there was no change in the esophageal location, and in the remaining seven patients (17%), its position had shifted by ≥1 cm (range 1.0–4.0 cm).
Conclusions: In more than 80% of patients presenting for a repeat LA ablation procedure, the esophagus is in the same position relative to the PVs as during the initial procedure. Therefore, if radiofrequency ablation at a particular location was limited by the position of the esophagus, safe ablation at that site is unlikely to be feasible during a repeat procedure.     

Mechanical esophageal displacement during catheter ablation for atrial fibrillation

Esophageal Deviation in AF Ablation. Objective: To determine the feasibility and safety of esophageal displacement during atrial fibrillation (AF) ablation, to prevent thermal injury. Background: Patients undergoing AF ablation are at risk of esophageal thermal injury, which ranges from superficial ulceration, to gastroparesis, to the rare but catastrophic atrioesophageal fistula. A common approach to avoid damage is luminal esophageal temperature (LET) monitoring; however, (1) temperature rises mandate interruptions in energy delivery that interrupt workflow and potentially decrease procedural efficacy, and (2) esophageal fistulas have been reported even with LET monitoring. Methods: A cohort of 20 consecutive patients undergoing radiofrequency (RF) (16 patients) or laser balloon (4 patients) ablation of AF under general anesthesia. After barium instillation, the esophagus was deviated using an endotracheal stylet placed within a thoracic chest tube. LET monitoring was used during catheter ablation. Upper GI endoscopy was performed prior to discharge. Results: At the pulmonary vein level, leftward deviation measured 2.8 ± 1.6 cm (range: 0.4–5.7) and rightward deviation 2.8 ± 1.8 cm (range: 0.5–4.9). The temperature rose to >38.5 °C in 3/20 (15%) patients. In these 3 patients, there was an average of 2 applications/patient that recorded temperatures >38.5 °C. No patient had a temperature rise > 40 °C. Endoscopy revealed no esophageal ulceration from thermal injury in 18/19 (95%) patients; the sole patient with a thermally mediated ulceration had an unusual esophageal diverticulum fully across the posterior left atrium. Twelve patients (63%) exhibited trauma related to instrumentation with no clinical sequelae. Conclusions: Mechanical esophageal deviation is feasible and allows for uninterrupted energy delivery along the posterior wall during catheter ablation of AF. J Cardiovasc Electrophysiol, Vol. 23, pp. 147‐154, February 2012)     

Combined management of esophagopericardial fistula sustained after catheter ablation for atrial fibrillation

Introduction: Radiofrequency ablation (RFA) is an effective treatment modality for atrial fibrillation (AF); however, serious complications can occur. We present the case of a highly morbid consequence, the esophagopericardial fistula (EPF). Case: A hemodynamically unstable patient with a history of AF and recent RFA presented with chest pain and was found to have pneumopericardium and pericardial effusion. The patient went to the operating room emergently for combined management with surgical pericardial window and endoscopic stent placement. Conclusion: EPF must be on the differential diagnosis while evaluating patients who develop constitutional symptoms or sudden onset chest pain days or weeks after catheter ablation for AF. Early detection followed by aggressive management with a combined surgical and endoscopic approach may be considered for successful treatment of this type of postablation esophageal perforation if an atrioesophageal fistula is effectively ruled out.     

Aorto-right atrial fistula following transseptal catheterization and catheter ablation for atrial fibrillation

Aorto-cameral fistula, either congenital or acquired, is an abnormal connection between the ascending aortic root and one of the cardiac chambers. We report a case of a 61-year-old male with history of atrial fibrillation and 2 radiofrequency ablation procedures, referred to us for surgical Cox Maze procedure. Preoperative cardiac computerized tomography revealed a fistulous connection between the aortic root and the right atrium. Later, the patient underwent successful surgical closure of the fistula during the Cox Maze procedure. In this paper, we also discuss the clinical presentation, natural history, anatomy of the interatrial septum, and management of aorto-cameral fistula.     

Atrioesophageal fistula after atrial fibrillation catheter ablation: A case report

Rationale:Atrioesophageal fistula (AEF) is a rare but serious complication of atrial fibrillation (AF) catheter ablation with associated high mortality rates.Patient concerns:A 42-year-old male patient who underwent catheter ablation in local hospital 20 days ago because of persistent AF was admitted to our Emergency Room with unconsciousness and high axillary temperature and white blood cell count. Craniocerebral CT scan found multiple infarct lesions in both frontal and occipital lobes. Pneumatosis between the left atrium and the esophagus was observed in the chest CT.Diagnoses:AEF.Interventions:We performed a salvage operation of the left atrium debridement, and left atrium patch repairing under extracorporeal circulation. We opened the mediastinum, and dissected the esophageal perforation. A special irrigating catheter with multiple side ports on the tip was placed from the esophagus to the posterior mediastinum through the esophageal orificium fistulae. We also inserted a gastrointestinal tube to the jejunum under gastroscopy. Three additional drainage tubes were inserted into the esophageal bed and the right thoracic cavity.Outcomes:The procedure was successful. But 7 days later, the patient''s family chose to forgo treatment due to multiple cerebral infarcts, respiratory and blood system infection, liver failure, and other complications.Lessons:AEF is a rare but fatal complication after catheter ablation. Heightened vigilance is required for early recognition of the AEF. Surgical treatment should be performed as early as possible, especially before the neurological complications occur.     

Approach and strategy for repeat catheter ablation of recurrent atrial fibrillation

Patients with atrial fibrillation often undergo repeat catheter ablation for the recurrence of tachyarrhythmia. If the pulmonary veins were isolated in prior procedure, the operator should focus on substrate homogenization with identification and ablation of only arrhythmogenic areas.     

Clinical outcome of very late recurrence of atrial fibrillation after catheter ablation of paroxysmal atrial fibrillation

INTRODUCTION: High recurrence rate is still a major problem associated with ablation of paroxysmal atrial fibrillation (AF). Most of the recurrences occur within 6 months after ablation. The characteristics of very late recurrent AF (>12 months after ablation) have not been reported. METHODS AND RESULTS: Two hundred seven patients with drug-refractory AF underwent successful focal ablation or isolation of AF foci. After the first ablation procedure, Holter monitoring and event recorders were used to evaluate symptomatic recurrent AF. A second ablation procedure was recommended if the antiarrhythmic drugs could not control recurrent AF. During long-term follow-up (mean 30 +/- 11 months, up to 51 months), 70 patients had recurrent AF, including 13 patients (6%) with very late (>12 months) recurrent AF (group 1) and 57 patients (28%) with late (within 12 months after ablation) recurrent AF (group 2). Group 1 patients had a significantly lower incidence of multiple (> or = 2) AF foci (23% vs 63%, P = 0.02) than group 2 patients. In addition, the incidence of antiarrhythmic drugs use (38% vs 84%, P = 0.001) to maintain sinus rhythm after the first episode of recurrent AF was significantly lower in group 1 than group 2 patients, and the incidence of a second intervention procedure (8% vs 35%, P = 0.051) tended to be lower in group 1 than group 2 patients. CONCLUSION: The incidence of very late recurrent AF after ablation of paroxysmal AF is very low, and the clinical outcome of patients with very late recurrent AF is benign.     

Complications of catheter ablation for atrial fibrillation: incidence and predictors

Introduction: Pulmonary vein (PV) isolation by catheter ablation is an increasingly used strategy to treat atrial fibrillation (AF). Complication rates from AF ablation reported in different case series vary widely. We conducted a retrospective analysis of 641 consecutive ablation procedures to assess complication rates, temporal trends, and clinical predictors of adverse outcomes.
Methods: All patients (n = 517) undergoing catheter ablation for AF at Johns Hopkins Hospital between February, 2001 and June, 2007 were prospectively enrolled in a database. Data from 641 consecutive procedures were analyzed and complications considered if they occurred within 30 days of ablation. Major complications were defined as those that required intervention, resulted in long-term disability, or prolonged hospitalization.
Results: Thirty-two major complications occurred in 641 procedures (5%). Among the patients with major complications, seven had cerebrovascular accident (CVA), eight had tamponade, one had PV occlusion with hemoptysis, and 11 had vascular injury requiring surgical repair and/or transfusion. No periprocedural deaths occurred, and no instances of esophageal injury were seen. Complication rates were higher during the first 100 cases (9.0%) than during the subsequent 541 (4.3%). Major adverse clinical events were associated with age > 70 years (P = 0.007; odds ratio 3.7, 95% confidence interval 1.4–9.6) and female gender (P = 0.014; odds ratio 3.0, 95% confidence interval 1.3–7.2). No other clinical or procedural predictors of complication were identified.
Conclusions: Complication rates from AF ablation remain significant, despite improved techniques and increased awareness of procedural risks. Both advanced age and female gender predict major adverse events, suggesting careful consideration of the risk/benefit profile in these patients prior to ablation.     

长程持续性房颤消融术中规整房速的处理

目的探索慢性房颤导管消融中规则房速的发生机制与处理方法。方法选择2009年1月至2013年5月在厦门心脏中心确诊并接受导管消融治疗的慢性房颤患者102例,采用递进式导管消融策略,分析慢性房颤患者在消融中发生规则房速的可能机制并进行相应处理。结果102例患者中,4例（4．9％）在肺静脉电隔离过程中转为窦律,3例（2．9％）在行碎裂电位消融时转为窦律,46例经碎裂电位消融及心房线性消融过程中转为规则房速（45．1％）,47例（46．1％）仍维持房颤。规则房速的发生机制为局灶自律性（17．6％）、折返性（77．8％）、其它（4．6％）,消融成功率为81．6％。结论慢性房颤递进式导管消融中,规则房速的发生机制多为大折返性,导管消融此类房速成功率较高。     

Predictors of recurrence following catheter ablation of atrial fibrillation using an irrigated-tip ablation catheter

INTRODUCTION: The aims of this study were to identify predictors of recurrence after catheter ablation of atrial fibrillation (AF) and to report the safety and efficacy of catheter ablation of AF using an irrigated-tip ablation catheter. METHODS AND RESULTS: Seventy-five consecutive patients (51 men [68%]; age 54 +/- 13 years) with symptomatic drug-refractory paroxysmal (42 patients), persistent (21 patients), or permanent (12 patients) AF underwent catheter ablation of AF using an irrigated-tip ablation catheter and a standard ablation strategy, which involved electrical isolation of all pulmonary veins (PVs) and creation of a cavotricuspid linear lesion. At 10.5 +/- 7.5 months of follow-up following a single (n = 75) or redo ablation procedure (n = 11), 39 (52%) of the 75 patients were free of AF, 10 were improved (13%), and 26 had experienced no benefit from the ablation procedure (35%). Seventy-six percent of patients with paroxysmal AF were free from recurrent AF. The most significant complications were two episodes of pericardial tamponade, mitral valve injury in one patient, two strokes, and complete but asymptomatic PV stenosis in one patient. Cox proportional hazards multivariate regression analysis identified the presence of persistent AF, permanent AF, and age >50 years prior to the ablation are the only independent predictors of AF recurrence after the first PV isolation procedure. CONCLUSION: Catheter ablation of AF using a strategy involving isolation of all PVs and creation of a linear lesion in the cavotricuspid isthmus using cooled radiofrequency energy is associated with moderate efficacy and an important risk for complications. The best results of this procedure are achieved in the subset of patients who are younger than 50 years and have only paroxysmal AF.     

导管射频消融治疗高龄心房颤动患者的临床评价

目的评价高龄心房颤动(AF)患者接受导管射频消融治疗的有效性和安全性。方法纳入2008年1月至2014年8月在大连医科大学附属第一医院行房颤射频消融(RA)的877例患者,按年龄分为老年组(≥75岁)68例、年轻老年组(65～74岁)320例及对照组(65岁)489例。记录3组患者的临床资料,分析对比3组患者术中并发症、手术时间、X线曝光时间,比较术后血栓栓塞率、再住院率、二次手术率、术后抗心律失常药物服用率以及术后缓慢心室率比例。消融成功的定义:术后心电图或动态心电图未再出现持续时间超过30 s的房颤。采用SPSS 19.0统计软件,根据数据类型分别采用x~2检验、方差分析或LSD检验进行分析。应用Kaplan-Meier分析分别比较持续性AF和阵发性AF不同年龄患者的导管消融成功率。结果消融过程及安全性评价:3组患者术中并发症(5.9%vs 3.1%vs 2.9%)、手术时间[(196.65±34.45)vs(196.03±40.02)vs(194.36±37.89)min]、X射线曝光时间[(19.81±6.73)vs(19.44±6.45)vs(18.69±6.00)min],差异均无统计学意义。疗效评价:3组患者随访(21.45±6.31)个月,其术后血栓栓塞率(4.4%vs 3.4%vs 2.5%)、再住院率(23.5%vs 22.2%vs18.0%)及二次手术率(11.8%vs 12.8%vs 12.3%),差异无统计学意义。但是,老年组患者在术后长期使用抗心律失常药物的比例相对较低(13.2%vs 29.4%vs 20.0%,P=0.001),术后动态心电图出现缓慢心室率的比例较高(23.5%vs 15.6%vs12.3%,P=0.033)。Kaplan-Meier生存分析结果显示持续性AF和阵发性AF不同年龄患者的导管消融成功率差异无统计学意义。结论老年心房颤动患者的导管消融成功率和安全性与年轻患者相似。     

Radiofrequency catheter ablation of atrial fibrillation initiated by pulmonary vein ectopic beats

Ectopic beats from the pulmonary veins (PVs) have been demonstrated to initiate atrial fibrillation (AF). This article describes the conceptual approach to mapping, interpretation of different electrograms, and ablation of AF initiated by PV ectopic beats.     

Prevalence of asymptomatic recurrences of atrial fibrillation after successful radiofrequency catheter ablation

INTRODUCTION: The long-term efficacy of radiofrequency catheter ablation of atrial fibrillation (AF) has been based on patient-reported symptoms suggestive of AF. However, asymptomatic recurrences of AF may remain undetected. The aim of this study was to determine the prevalence of asymptomatic recurrences of AF after an apparently successful catheter ablation procedure for AF. METHODS AND RESULTS: Among 244 consecutive patients (mean age 53 +/- 11 years) who underwent a pulmonary vein isolation procedure for symptomatic paroxysmal AF and who reported no symptoms of recurrent AF at > or =6 months after the procedure, 60 patients with a history of > or =1 episode of AF per week were asked to participate in this study. Preablation, these patients had experienced 19 +/- 13 episodes of AF per month. The patients were provided with a patient-activated transtelephonic event recorder for 30 days, a mean of 642 +/- 195 days after the ablation procedure, and were asked to record and transmit recordings on a daily basis and whenever they felt palpitations. Seven patients (12%) felt palpitations during the study, although they had not experienced symptoms previously. Each of these 7 patients had an episode of AF documented with the event monitor during symptoms. In these 7 patients, the mean number of episodes per month decreased from 19 +/- 14 preablation to 3 +/- 1 postablation (P < 0.001). Among the 53 asymptomatic patients, an episode of AF was captured in 1 (2%) patient during the study period. CONCLUSION: Asymptomatic recurrences of AF after an apparently successful catheter ablation procedure for symptomatic paroxysmal AF are infrequent.     

EnSite NavX指导下无肺静脉造影的阵发性心房颤动导管消融术

目的探讨不作肺静脉造影行阵发性心房颤动(房颤)环肺静脉电隔离术的有效性和可行性。方法 34例阵发性房颤患者分为无肺静脉造影组(n=18)和肺静脉造影组(n=16),无肺静脉造影组不作肺静脉造影,余步骤与肺静脉造影组相同,两组均在EnSiteNavX三维标测系统指导下重建左心房及肺静脉,再分别行左、右环肺静脉电隔离术,消融终点为肺静脉与心房完全电隔离。结果无肺静脉造影组消融术时间[(92.78±19.46)minvs.(106.44±20.18)min,P0.05]及X-线曝光时间[(11.47±4.32)minvs.(16.06±8.72)min,P0.05]少于肺静脉造影组,差异有统计学意义。两组左心房三维重建时间[(6.22±2.65)minvs.(6.31±3.00)min,P0.05]、左、右侧环肺静脉消融时间[(21.61±7.66)minvs.(20.50±8.09)min,P0.05;(17.33±10.22)minvs.(17.48±7.86)min,P0.05]及即刻消融成功率[100%(18/18)vs.100%(16/16),P0.05]比较,差异无统计学意义。结论不作肺静脉造影,仅在三维标测系统指导下行房颤消融治疗,可达到相同消融效果,可节省消融术及X-线曝光时间,减少手术步骤、耗材和费用。     

老年心房颤动不同方式的经导管射频消融治疗

目的研究不同方式经导管射频消融治疗对老年房颤的治疗效果。方法53例房颤患者，男性38例，女性15例，年龄60-83岁。按接受不同的经导管消融方法将上述患者分为3组：消融隔离肺静脉治疗阵发性房颤组20例、消融典型房扑治疗房颤合并房扑组26例、消融房室传导加植入永久性起搏器治疗持续性房颤伴药物难以控制的快速心室率和（或）心力衰竭组7例。结果消融隔离肺静脉组中15例采用环状标测电极导管引导电隔离3～4根肺静脉成功，术后无房颤发作8例（53％），房颤发作明显减少4例（27％）；采用电解剖系统引导下环双侧肺静脉线性消融隔离肺静脉5例，无房颤发作4例（80％）。消融房扑组26例典型房扑均消融成功，随访中15例（58％）无房颤发作，8例（31％）房颤发作较前减少。经导管消融房室传导组7例全部成功，4例行右心室、3例行双心室VVI模式起搏，随访中生活质量和（或）心力衰竭症状明显改善。结论针对不同类型的老年房颤患者采用不同的经导管消融方法可以取得较好的临床效果。