Radiofrequency Ablation (radiofrequency + ablation)

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Radiofrequency Ablation

  • percutaneou radiofrequency ablation

  • Selected Abstracts

    Lobectomy for Pulmonary Vein Occlusion Secondary to Radiofrequency Ablation

    Pulmonary Vein Occlusion After RF Ablation., Pulmonary vein stenosis, a recognized complication of transcatheter radiofrequency ablation in the left atrium, is often asymptomatic. Significant stenosis is commonly treated with percutaneous balloon dilation with or without stenting. We encountered a case of complete pulmonary vein occlusion that caused lobar thrombosis, pleuritic pain, and persistent cough. Imaging studies revealed virtually no perfusion to the affected lobe. A lobectomy was performed, resolving the persistent cough and pain. Pulmonary vein occlusion should be suspected in patients who present with pulmonary symptoms after having undergone ablative procedures for atrial fibrillation. This condition may necessitate surgical intervention if interventions such as balloon dilation or stenting are not possible or are ineffective.,(J Cardiovasc Electrophysiol, Vol. 21, pp. 1055-1058, September 2010) [source]

    Effect of Radiofrequency Ablation of Atrial Flutter on the Natural History of Subsequent Atrial Arrhythmias

    Introduction: Patients with atrial flutter (AFL) treated medically are at high risk for subsequent development of atrial fibrillation (AF). Whether curative radiofrequency ablation of AFL can modify the natural history of arrhythmia progression is not clear. We aimed to determine whether ablation of AFL decreases the subsequent development of AF in patients without previous AF. Methods and Results: Patients with AFL as the sole atrial arrhythmia were selected from patients who underwent successful AFL ablation at Mayo Clinic between 1997 and 2003 (N = 137). The cohort was divided by presence (n = 50) or absence (n = 87) of structural heart disease. A control group comprised 59 patients with AFL and no history of paroxysmal AF, who received only medical therapy. Occurrence of AF after AFL ablation was compared among study groups and controls. Symptomatic AF occurred in 49 patients during 5 years of follow-up after AFL ablation, with similar frequency in both study groups. The cumulative probability of paroxysmal and chronic AF was similar in controls and each study group. By multivariate analysis, the AFL ablation procedure carries significant risk of AF occurrence during follow-up. Fifty patients discontinued antiarrhythmic drugs after AFL ablation, and the rate of cardioversions decreased. Conclusion: Successful ablation of AFL does not improve the natural history of atrial arrhythmia progression; postablation AF is frequent. This suggests that AFL may be initiated by bursts of AF and that in the absence of AFL substrate the AF continues to progress. [source]

    Esophageal Luminal Temperature Measurement Underestimates Esophageal Tissue Temperature During Radiofrequency Ablation Within the Canine Left Atrium: Comparison Between 8 mm Tip and Open Irrigation Catheters

    Introduction: Evaluation of luminal temperature during left atrial ablation is used clinically; however, luminal temperature does not necessarily reflect temperature within the esophageal wall and poses a risk of atrioesophageal fistula. This animal study evaluates luminal esophageal temperature and its relation to the temperature of the external esophageal tissue during left atrial lesions using the 8 mm solid tip and the open irrigated tip catheters (OIC). Methods and Results: A thermocouple was secured to the external surface of the esophagus at the level of the left atrium of the dogs. Luminal esophageal temperature was measured using a standard temperature probe. In four randomized dogs, lesions were placed using an 8 mm solid tip ablation catheter. In six randomized dogs, lesions were placed using the 3.5 mm OIC. The average peak esophageal tissue temperature when using the OIC was significantly higher than that of the 8 mm tip catheter (88.6C 15.0C vs. 62.3C 12.5C, P < 0.05). Both OIC and 8 mm tip catheter had significantly higher peak tissue temperatures than luminal temperatures (OIC: 88.6C 15.0C vs 39.7C 0.82C, P < 0.05) (8 mm: 62.3C 12.5C vs 39.0 0.5C, P < 0.05). Both catheters achieved peak temperatures faster in the tissue as compared to the lumen of the esophagus, although the tissue temperature peaked significantly faster for the OIC (OIC: 25 seconds vs 90 seconds, P < 0.05) (8 mm: 63 seconds vs 105 seconds, P < 0.05). Conclusion: Despite the significant difference in actual tissue temperatures, no significant difference was observed in luminal temperatures between the OIC and 8 mm tip catheter. [source]

    Pain and Anatomical Locations of Radiofrequency Ablation as Predictors of Esophageal Temperature Rise During Pulmonary Vein Isolation

    Introduction: Esophageal temperature rise (ETR) during ablation inside left atrium has been reported as a marker for esophageal thermal injury. We sought to investigate the possible relationships between chest pain and ETR during radiofrequency (RF) ablation, and ETR and locations of RF application, in patients undergoing pulmonary vein (PV) isolation under moderate sedation. Methods and Results: We analyzed anatomical locations of each RF application and its association with esophageal temperature and presence/absence of pain. Data from 40 consecutive patients (mean age: 56 10 years) were analyzed. There were a total of 4,071 RF applications resulting in 291 episodes of pain (7.1%) and 223 ETRs (5.5%). Thirty-five patients (87.5%) experienced at least one pain episode and 32 (80.0%) had at least one ETR. While 77.4% of posterior wall applications that caused pain also corresponded to an ETR (P < 0.0001), only 0.8% of pain-free posterior wall applications were associated with ETRs (P < 0.0001). The sensitivity and specificity of pain during ablation for ETR were 94% and 98%, respectively. No ETRs were observed during anterior wall applications. ETRs occurred more frequently during ablation on the left (86.1%) versus the right (13.9%), and in inferior (70.4%) versus superior (29.6%) segments. Conclusion: In patients undergoing PV isolation, ETR was encountered when ablating in the posterior left atrium with the distribution left > right and inferior > superior. Pain during ablation was associated with ETR, and lack of pain was strongly associated with absence of ETR. Pain during RF ablation may thus serve as a predictor of esophageal heating and potential injury. [source]

    Time Course of Esophageal Lesions After Catheter Ablation with Cryothermal and Radiofrequency Ablation: Implication for Atrio-Esophageal Fistula Formation After Catheter Ablation for Atrial Fibrillation

    Background: Atrio-esophageal fistulas have been described as a consequence of radiofrequency (RF) ablation for the treatment of atrial fibrillation (AF). However, whether cryoablation can avoid this potential fatal complication remains unclear. Methods and Results: We studied the effects of direct application of RF and cryoablation on the cervical esophagus in 16 calves. Cryoablation was performed with a 6.5-mm catheter probe using a single 5-minute freeze at <,80C, and RF ablation was delivered with an 8-mm catheter electrode at 50 W and 50C for 45,60 seconds. Histopathologic assessments were performed at 1, 4, 7, and 14 day(s) after completion of the ablation protocol: four animals were examined each day. A total of 85 direct esophageal ablations were performed: 41 with RF and 44 with cryoablation. There were no significant differences in lesion width, depth, or volume between cryoablation and RF ablation at Day 1, 4, and 14 after the procedure (P > 0.05). However, lesion width and volume were significantly larger with RF than with cryoablation at Day 7. Although acute (Day 1) and chronic (Day 14) RF and cryoablation lesions were of comparable size, histologic evidence of partial- to full-wall esophageal lesion ulceration was observed in 0 of 44 (0%) lesions with cryoablation, compared with 9 of 41 (22%) lesions with RF ablation (P = 0.0025). Conclusions: Direct application of cryoablation and RF ablation created similar acute and chronic lesion dimensions on the esophagus. However, cryoablation was associated with a significantly lower risk of esophageal ulceration, compared with RF ablation. [source]

    Tako-tsubo Cardiomyopathy Complicating Left Atrial Radiofrequency Ablation

    Two female patients undergoing left atrial radiofrequency catheter ablation developed Tako-tsubo cardiomyopathy. This reversible form of left ventricular dysfunction is known to occur under conditions associated with marked sympathetic nervous activation. Radiofrequency catheter ablation in the left atrium can damage autonomic ganglionated plexi, leading to vagal withdrawal, thus resulting in enhanced sympathetic tone. Tako-tsubo cardiomyopathy has not been previously described following radiofrequency catheter ablation. [source]

    Focal Atrial Tachycardia Originating from the Left Atrial Appendage: Electrocardiographic and Electrophysiologic Characterization and Long-Term Outcomes of Radiofrequency Ablation

    Introduction: This study sought to investigate electrophysiologic characteristics and radiofrequency ablation (RFA) in patients with focal atrial tachycardia (AT) arising from the left atrial appendage (LAA). Methods: This study included seven patients undergoing RFA with focal AT. Activation mapping was performed during tachycardia to identify an earlier activation in the left atria and the LAA. The atrial appendage angiography was performed to identify the origin in the LAA before and after RFA. Results: AT occurred spontaneously or was induced by isoproterenol infusion rather than programmed extrastimulation and burst atrial pacing in any patient. The tachycardia demonstrated a characteristic P-wave morphology and endocardial activation pattern. The P wave was highly positive in inferior leads in all patients. Lead V1 showed upright or biphasic () component in all patients. Lead V2,V6 showed an isoelectric component in five patients or an upright component with low amplitude (<0.1 mV) in two patients. Earliest endocardial activity occurred at the distal coronary sinus (CS) ahead of P wave in all seven patients. Mean tachycardia cycle length was 381 34 msec and the earliest endocardial activation at the successful RFA site occurred 42.3 9.6 msec before the onset of P wave. RFA was acutely successful in all seven patients. Long-term success was achieved in seven of the seven over a mean follow-up of 24 5 months. Conclusions: The LAA is an uncommon site of origin for focal AT (3%). There were consistent P-wave morphology and endocardial activation associated with this type of AT. The LAA focal ablation is safe and effective. Long-term success was achieved with focal ablation in all patients. [source]

    Human Histopathology of Electroanatomic Mapping After Cooled-Tip Radiofrequency Ablation to Treat Ventricular Tachycardia in Remote Myocardial Infarction

    Introduction: Catheter ablation of ventricular tachycardia (VT) in remote myocardial infarction (MI) often requires excessive mapping procedures. Documentation of the electrical substrate via electrogram amplitude may help to identify regions of altered myocardium resembling exit areas of reentrant VTs. Methods and Results: A patient with multiple symptomatic monomorphic VTs (biventricular ICD, remote MI) underwent electroanatomic substrate mapping (CARTO) for VT ablation. Regions of scar (bipolar electrogram amplitudes ,0.5 mV), normal myocardium (,1.5 mV), and "altered" myocardium (0.5,1.5 mV) were identified. Ablation was directed to regions with "altered" myocardium based on pace map correlation. After ablation the clinical VT did not reoccur. The patient died due to worsening of heart failure 7 days afterward. During postmortal evaluation specified sites of electroanatomic mapping were correlated to histopathological findings. Annotated scar areas were documented to consist of areas with massive fibrosis (,80% of mural composition). Ablations were found to span through regions with intermediate fibrosis (21,79%) mapped as "altered" myocardium. Ablation produced transmural coagulation necrosis of mesh-like fibrotic tissue with interspersed remnants of myocardial cells up to a maximum depth of 7.0 mm. Subendocardial intramural bleedings were universal findings 7 days after ablation. Conclusions: Electroanatomic substrate mapping for VT ablation sufficiently identified regions of scar and normal myocardium. Regions with bipolar electrogram amplitudes between 0.5 and 1.5 mV were found to correlate to areas of "intermediate" fibrosis (21,79%) with only remnant strands of myocardial cells and were identified as target region for ablation. Cooled-tip endocardial radiofrequency ablation lead to transmural coagulation necrosis up to a depth of 7.0 mm. [source]

    Quality Improvement in Pediatric Radiofrequency Ablation

    No abstract is available for this article. [source]

    Left Atrial Radiofrequency Ablation During Cardiac Surgery in Patients with Atrial Fibrillation

    Introduction: Intraoperative left atrial radiofrequency (RF) ablation recently has been suggested as an effective surgical treatment for atrial fibrillation (AF). The aim of this study was to verify the outcome of this technique in a controlled multicenter trial. Methods and Results: One hundred three consecutive patients (39 men and 65 women; age 62 11 years) affected by AF underwent cardiac surgery and RF ablation in the left atrium (RF group). The control group consisted of 27 patients (6 men and 21 women; age 64 7 years) with AF who underwent cardiac surgery during the same period and refused RF ablation. Mitral valve disease was present in 89 (86%) and 25 (92%) patients, respectively (P = NS). RF endocardial ablation was performed in order to obtain isolation of both right and left pulmonary veins, a lesion connecting the previous lines, and a lesion connecting the line encircling the left veins to the mitral annulus. Upon discharge from the hospital, sinus rhythm was present in 65 patients (63%) versus 5 patients (18%) in the control group (P < 0.0001). Mean time of cardiopulmonary bypass was longer in the RF group (148 50 min vs 117 30 min, P = 0.013). The complication rate was similar in both groups, but RF ablation-related complications occurred in 4 RF group patients (3.9%). After a mean follow-up of 12.5 5 months (range 4,24), 83 (81%) of 102 RF group patients were in stable sinus rhythm versus 3 (11%) of 27 in the control group (P < 0.0001). The success rate was similar among the four surgical centers. Atrial contraction was present in 66 (79.5%) of 83 patients in the RF group in sinus rhythm. Conclusion: Endocardial RF left atrial compartmentalization during cardiac surgery is effective in restoring sinus rhythm in many patients. This technique is easy to perform and reproducible. Rare RF ablation-related complications can occur. During follow-up, sinus rhythm persistence is good, and biatrial contraction is preserved in most patients. (J Cardiovasc Electrophysiol, Vol. 14, pp. 1289-1295, December 2003) [source]

    Latent Mahaim Fiber as a Cause of Antidromic Reciprocating Tachycardia: Recognition and Successful Radiofrequency Ablation

    Latent Mahaim Fiber. The term "Mahaim fiber" usually is applied to an atriofascicular fiber that inserts distally into the right bundle branch and forms the anterograde limb of a reciprocating tachycardia. One of the features that has been used to describe the physiology of Mahaim fibers is the presence of anterograde preexcitation. We describe two patients who had a clinical tachycardia consistent with a "Mahaim tachycardia" in whom there was no evidence or minimal evidence of anterograde preexcitation during sinus rhythm or atrial pacing. In both patients, the tachycardia was rendered noninducible by radiofrequency ablation at the site of Mahaim potentials at the tricuspid annulus, and a long-term cure was achieved. This is the first description of a "latent Mahaim fiber" that does not cause preexcitation but which can support antidromic reciprocating tachycardia. [source]

    Three-Dimensional Catheter Positioning During Radiofrequency Ablation in Patients: First Application of a Real-Time Position Management System

    Three-Dimensional Reai-Time Position Management. Introduction: Precise localization of target sites for radiofrequency catheter ablation (RFCA) of arrhythmias is hampered by the relative inaccuracy of X-ray localization procedures. This study evaluated the efficacy of a three-dimensional (3D) real-time position management system in guiding RFCA procedures in patients. Methods and Results: Patients (n = 30, age 59 20 years) referred for ablation of either atrial flutter (n = 10), ventricular tachycardia (n = 15), or accessory pathways (n = 5) were studied. The real-time position management system uses ultrasound ranging techniques to track the position of an ablation catheter relative to two multitransducer reference catheters, positioned in the right atrium or coronary sinus and the right ventricle. Each catheter contains three or four ultrasound transducers. The distance between the transducer(s) is determined hy calculating the time necessary for an ultrasound pulse to reach other transducers, assuming the speed of sound in blood is 1,550 m/sec. The proximal His bundle was marked at the beginning and the end of the procedure as an electrical landmark to verify reproducibility. After identification of target sites, the position of each lesion created with the ablation catheter was marked. Successful ahlation was achieved in 94% of the patients. The distance between the location of the proximal His hundle as marked at the beginning and at the end of the procedure was 2.0 1.2 mm (range 1.5 to 3.5). Conclusion: The new 3D real-time position management system facilitated RFCA procedures as it allowed accurate and reproducible 3D tracking of the mapping and ablation catheter. [source]

    Feasibility of Myxomatous Mitral Valve Repair Using Direct Leaflet and Chordal Radiofrequency Ablation

    Objective: Minimally invasive repair of mitral valve prolapse (MVP) causing severe mitral regurgitation (MR) should reduce MR and have chronic durability. Our ex vivo, acute in vivo, and chronic in vivo studies suggest that direct application of radiofrequency ablation (RFA) to mitral leaflets and chordae can effect these repair goals to decrease MR. Methods: A total of seven canines were studied to assess the effects of RFA on mitral valve structure and function. RFA was applied ex vivo (n = 1), acutely in vivo using a right lateral thoracotomy and cardiopulmonary bypass (n = 3), and chronically in vivo using percutaneous access to the heart (n = 3). RFA was applied to the mitral valve and its associated chordae. Mitral valve structure and function (in vivo preparations) were then assessed. Results: Ex vivo application of RFA resulted in qualitative reduction in mitral leaflet surface area and chordal length. Acute in vivo application of RFA to canines found to have MVP causing severe MR demonstrated a 43.7,60.7% statistically significant (P = 0.039) reduction in postablation MR. Chronic, in vivo, percutaneous application of RFA was found to be feasible and the engendered alterations durable. Conclusion: These data suggest that myxomatous mitral valve repair using radiofrequency energy delivered via catheter is feasible. [source]

    Cavotricuspid Isthmus: Anatomy, Electrophysiology, and Long-Term Outcome of Radiofrequency Ablation

    Ching-Tai Tai M.D.
    The cavotricuspid isthmus (CTI) had a complex architecture with an anisotropic conduction property. An incremental pacing from the low right atrial isthmus produced a conduction delay and block, and initiated atrial flutter. Radiofrequency catheter ablation of the CTI was very effective in eliminating the typical atrial flutter. However, atrial fibrillation often occurred after ablation of the isthmus and needs further treatment. [source]

    Radiofrequency Ablation of a "Concealed" Mahaim-Type Accessory Pathway

    We report a case of supraventricular tachycardia associated with left bundle branch block due to a slowly conducting right sided accessory pathway. Preexcitation of the ventricles could not be demonstrated during sinus rhythm or incremental atrial pacing but its presence was confirmed during antedromic tachycardia with critically timed atrial extrastimuli. The pathway was mapped during tachycardia and successfully ablated. [source]

    Improvement in Quality of Life after Radiofrequency Ablation

    No abstract is available for this article. [source]

    High Incidence of Thrombus Formation Without Impedance Rise During Radiofrequency Ablation Using Electrode Temperature Control

    The authors hypothesized that during RF ablation, the electrode to tissue interface temperature may significantly exceed electrode temperature in the presence of cooling blood flow and produce thrombus. In 12 anesthetized dogs, the skin over the thigh muscle was incised and raised to form a cradle that was superfused with heparinized canine blood(ACT > 350 s)at 37C. A 7 Fr, 4-mm or 8-mm ablation electrode containing a thermocouple was held perpendicular to the thigh muscle at 10-g contact weight. Interface temperature was measured at opposite sides of the electrode using tiny optical probes. RF applications(n = 157)were delivered at an electrode temperature of 45C, 55C, 65C, and 75C for 60 seconds, with or without pulsatile blood flow (150 mL/min). Without blood flow, the interface temperature was similar to the electrode temperature. With blood flow, the interface temperature (side opposite blood flow) was up to 36C and 57C higher than the electrode temperature using the 4- and 8-mm electrodes, respectively. After each RF, the cradle was emptied and the electrode and interface were examined. Thrombus developed without impedance rise at an interface temperature as low as 73C without blood flow and 80C with blood flow (11/16 RFs at 65C electrode temperature using 4 mm and 13/13 RFs at an electrode temperature of 55C using an 8-mm electrode with blood flow). With blood flow, interface temperature markedly exceeded the electrode temperature and the difference was greater with an 8-mm electrode (due to greater electrode cooling). In the presence of blood flow, thrombus occurred without an impedance rise at an electrode temperature as low as 65C with a 4-mm electrode and 55C with an 8-mm electrode. (PACE 2003; 26:1227,1237) [source]

    Feasibility of Pulmonary Vein Ostia Radiofrequency Ablation in Patients with Atrial Fibrillation: A Multicenter Study (CACAF Pilot Study)

    STABILE, G., et al.: Feasibility of Pulmonary Vein Ostia Radiofrequency Ablation in Patients with Atrial Fibrillation: A Multicenter Study (CACAF Pilot Study)Radiofrequency (RF) catheter ablation has been proposed as a treatment of atrial fibrillation (AF). Several approaches have been reported and success rates have been dependent on procedural volume and operator's experience. This is the first report of a multicenter study of RF ablation of AF. We treated 44 men and 25 women with paroxysmal(n = 40)or persistent(n = 29), drug refractory AF. Circular pulmonary vein (PV) ostial lesions were deployed transseptally, during sinus rhythm(n = 42)or AF(n = 26), under three-dimensional electroanatomic guidance. Cavo-tricuspid isthmus ablation was performed in 27 (40%) patients. The mean procedure time was215 76minutes (93,530), mean fluoroscopic exposure32 14minutes (12,79), and mean number of RF pulses per patient56 29(18,166). The mean numbers of separate PV ostia mapped and isolated per patient were3.9 0.5, and3.8 0.7, respectively. Major complications were observed in 3 (4%) patients, including pericardial effusion, transient ischemic attack, and tamponade. At 1-month follow-up, 21 of 68 (31%) patients had had AF recurrences, of whom 8 required electrical cardioversion. After the first month, over a mean period of9 3(5,14) months, 57 (84%) patients remained free of atrial arrhythmias. RF ablation of AF by circumferential PV ostial ablation is feasible with a high short-term success rate. While the procedure and fluoroscopic exposure duration were short, the incidence of major cardiac complications was not negligible. (PACE 2003; 26[Pt. II]:284,287) [source]

    Standardized Stimulation Protocol to Predict the Long-Term Success of Radiofrequency Ablation of Postinfarction Ventricular Tachycardia

    O'DONNELL, D., et al.: Standardized Stimulation Protocol to Predict the Long-Term Success of Radiofrequency Ablation of Postinfarction Ventricular Tachycardia.Background: The ability to predict the success of radiofrequency ablation (RFA) is an essential step in the management of ventricular tachycardia (VT) in patients with ischemic heart disease. Methods: This study tested a standardized programmed stimulation protocol and pre-specified definitions of procedural outcome. Consecutive patients referred for RFA of delayed post infarction VT were enrolled. Programmed stimulation was performed at the beginning and the end of an RFA procedure, and consisted of an 8 beat drive followed by up to 5 extrastimuli. Immediate success was defined as no inducible monomorphic VT, and a modified result was defined as the inducibility of VT with >2 extrastimuli beyond those required at baseline. Procedural failure was defined when these criteria were not met. Recurrences of sustained VT and arrhythmic deaths were monitored during long-term follow-up. Results: The study enrolled 112 patients. Immediate procedural success was achieved in 38%, a modified result in 34%, and procedural failure in 28% of patients. During a mean follow-up of 78 16 months, recurrent sustained VT was observed in 25 patients. VT recurrence was 3% (3/79) in patients with a successful or modified result, compared with 67% (22/33) in those who had undergone unsuccessful procedures (P < 0.001). Conclusions: This standardized stimulation protocol and definitions of procedural success, enabled us to predict with high accuracy a VT recurrence-free long-term follow-up. This may have implications in recommending devices or other treatments after RFA for postinfarction VT. (PACE 2003; 26[Pt. II]:348,351) [source]

    Bidirectional Ventricular Tachycardia After Radiofrequency Ablation of Idiopathic Left Ventricular Tachycardia

    No abstract is available for this article. [source]

    Reversible Cardiomyopathy After Radiofrequency Ablation of Lateral Free-Wall Pathway-Mediated Incessant Supraventricular Tachycardia

    Incessant supraventricular tachycardia leading to reversible Cardiomyopathy has been reported. Cardiomyopathy usually only develops after prolonged episodes of tachycardia at a significant heart rate. Left ventricular free-wall pathways rarely cause fast and incessant tachycardia. Therefore Cardiomyopathy has not been reported with left ventricular free-wall pathway-mediated supraventricular tachycardia. We report on two cases of left ventricular free-wall-mediated supraventricular tachycardia leading to reversible Cardiomyopathy after radiofrequency ablation. These cases illustrate the difficulty in diagnosing tachycardia-mediated Cardiomyopathy, as the tachycardia may be clinically silent. In addition, they emphasize the importance of making this diagnosis, as the Cardiomyopathy is reversible. [source]

    Safety of Pacemaker Implantation Prior to Radiofrequency Ablation of Atrioventricular Junction in a Single Session Procedure

    RF current delivery may cause acute and chronic dysfunction of previously implanted pacemakers. The aim of this study was to assess prospectively the effects of RF energy on Thera I and Kappa pacemakers in 70 consecutive patients (mean age 70 11 years, mean left ventricular ejection fraction 48 15%) who underwent RF ablation of the AV junction for antiarrhythmic drug refractory atrial fibrillation (permanent in 42 patients, paroxysmal in 28). These pacing systems incorporate protection elements to avoid electromagnetic interference. The pacemakers (Thera DR 7960 I in 20 patients, Thera SR 8960 1 in 30, Kappa DR 600,601 in 8, Kappa SR 700,701 in 12) were implanted prior to RF ablation in a single session procedure and were transiently programmed to VVI mode at a rate of 30 beats/min. Capsure SP and Z unibipolar leads were used. During RF application there was continuous monitoring of three ECG leads, endocavitary electrograms, and event markers. Complete AV block was achieved in all cases after 3.6 2.9 RF pulses and 100 75 seconds of RF energy delivery. The mean time of pacemaker implantation and RF ablation was 60 20 minutes. Transient or permanent pacemaker dysfunction including under/oversensing, reversion to a "noise-mode" pacing, pacing inhibition, reprogramming, or recycling were not observed. Leads impedance, sensing, and pacing thresholds remained in the normal range in the acute and long-term phase (average follow-up 18 12 months). In conclusion, Thera I and Kappa pacemakers exhibit excellent protection against interference produced by RF current. The functional integrity of the pacemakers and Capsure leads was observed in the acute and chronic phases. Thus, the implantation of these pacing systems prior to RF ablation of the AV junction can be recommended. [source]

    Radiofrequency Ablation of a Posteroseptal Atrioventricular Accessory Pathway in a Left-Sided Tricuspid Ring with Ebsteinlike Anomaly in a Patient with Congenitally Corrected Transposition of the Great Arteries

    Radiofrequency ablation successfully eliminated a posteroseptal accessory pathway in a left-sided tricuspid ring with Ebsteinlike anomaly in a patient with a congenially corrected transposition of the great arteries. [source]

    Pulsed Radiofrequency Ablation for Residual and Phantom Limb Pain: A Case Series

    PAIN PRACTICE, Issue 5 2010
    Matt West MD
    Abstract Residual limb pain (RLP) and phantom limb pain (PLP) can be debilitating and can prevent functional gains following amputation. High correlations have been reported between RLP and the stump neuromas following amputation. Many treatment methods including physical therapy, medications, and interventions, have been used with limited success. Pulsed radiofrequency ablation (PRFA) has shown promise in treating neuropathic pain because of the inhibition of evoked synaptic activity. We present 4 amputees who were treated with PRFA after failing conservative management for their RLP and PLP. All 4 patients underwent PRFA and demonstrated at least 80% relief of RLP for over 6 months. One patient reported a complete resolution of phantom sensation while another patient had significantly decreased frequency of spontaneous PLP and resolution of evoked PLP. In addition, all patients reported improved overall function including increased prosthetic tolerance and decreased oral pain medications. This case series suggests that PRFA is a viable treatment option which might be used for long-term relief of intractable RLP and/or PLP. [source]

    Trans-facet Joint Approach to Pulsed Radiofrequency Ablation of the L5 Dorsal Root Ganglion in a Patient with Degenerative Spondylosis and Scoliosis

    PAIN PRACTICE, Issue 3 2008
    David Abejn MD, FIPP
    ,,Abstract: Mechanical low back pain secondary to degenerative facet joint changes is a common reason for referral to pain clinics. When these changes cause encroachment into the intervertebral foramen, radicular pain may result. While pulsed radiofrequency of the dorsal root ganglion can be used in this setting, the anatomic deformity may make the transforaminal approach difficult. We report a case where a trans-facet approach was used successfully and describe the technique.,, [source]

    Radiofrequency Ablation for the Treatment of Mild to Moderate Obstructive Sleep Apnea

    THE LARYNGOSCOPE, Issue 11 2002
    Marc Bernard Blumen MD
    Abstract Objectives/Hypothesis Obstructive sleep apnea syndrome is due to pharyngeal obstructions, which can take place at the level of the soft palate. Temperature-controlled radiofrequency ablation has been introduced as being capable of reducing soft tissue volume and excessive compliance. The aim of the study was to evaluate prospectively the possible efficacy of temperature-controlled radiofrequency ablation applied to the soft palate in subjects with mild to moderate obstructive sleep apnea syndrome. Study Design Twenty-nine patients with a respiratory disturbance index between 10 and 30 events per hour, body mass index equal to or less than 30 kg/m2, and obstruction at the level of the soft palate were included in a pilot, prospective nonrandomized study. Methods Snoring and daytime sleepiness were evaluated subjectively. Treatment (maximum of three sessions) was discontinued when the bed partner was satisfied with the snoring level. A full night recording was performed at least 4 months after the last treatment. Results Mean snoring level decreased significantly from 8.6 1.3 to 3.3 2.5 on a visual analogue scale (0,10). Daytime sleepiness decreased nonsignificantly. Mean respiratory disturbance index decreased significantly from 19.0 6.1 events per hour to 9.8 8.6 events per hour. Mean lowest oxygen saturation value increased nonsignificantly from 85.3% 4.1% to 86.4% 4.4%. Of the patients, 65.5% were cured of their disease. Conclusions Temperature-controlled radiofrequency ablation was effective in selected patients with mild to moderate obstructive sleep apnea syndrome. A full-night polysomnography is required after completion of treatment to rule out residual disease. [source]

    ORIGINAL ARTICLE Clinical haemophilia: Remission of paroxysmal atrial fibrillation with iron reduction in haemophilia A

    HAEMOPHILIA, Issue 5 2010
    Summary., Two male first cousins with mild haemophilia A had baseline factor VIII levels of 12,15% and experienced bleeding requiring coagulation factor infusion therapy with trauma and surgical procedures. Both the patients with haemophilia A also had electrocardiographically documented symptomatic paroxysmal atrial fibrillation (PAF) for several years that had become resistant to pharmacological suppression. Radiofrequency ablation was considered in both the cases but deferred considering refusal of consent by the patients to undergo the procedure. Remission of arrhythmias has been reported in patients with iron-overload syndromes. Body iron stores assessed by serum ferritin levels were elevated in both men but neither had the C282Y or H63D genes for haemochromatosis. Calibrated reduction of iron stores by serial phlebotomy, avoiding iron deficiency, was followed by remission of symptomatic PAF in both cases. Iron reduction may be an effective treatment for arrhythmias apart from the classic iron-overload syndromes and deserves further study particularly in patients with bleeding disorders who might be at risk for arrhythmias and other diseases of ageing. [source]

    Loco-regional treatment of hepatocellular carcinoma,

    HEPATOLOGY, Issue 2 2010
    Riccardo Lencioni
    Loco-regional treatments play a key role in the management of hepatocellular carcinoma (HCC). Image-guided tumor ablation is recommended in patients with early-stage HCC when surgical options are precluded. Radiofrequency ablation has shown superior anticancer effects and greater survival benefit with respect to the seminal percutaneous technique, ethanol injection, in meta-analyses of randomized controlled trials, and is currently established as the standard method for local tumor treatment. Novel thermal and nonthermal techniques for tumor ablation,including microwave ablation, irreversible electroporation, and light-activated drug therapy,seem to have potential to overcome the limitations of radiofrequency ablation and warrant further clinical investigation. Transcatheter arterial chemoembolization (TACE) is the standard of care for patients with asymptomatic, noninvasive multinodular tumors at the intermediate stage. The recent introduction of embolic microspheres that have the ability to release the drug in a controlled and sustained fashion has been shown to significantly increase safety and efficacy of TACE with respect to conventional, lipiodol-based regimens. The available data for radioembolization with yttrium-90 suggests that this is a potential new option for patients with HCC, which should be investigated in the setting of randomized controlled trials. Despite the advances and refinements in loco-regional approaches, the long-term survival outcomes of patients managed with interventional techniques are not fully satisfactory, mainly because of the high rates of tumor recurrence. The recent addition of molecular targeted drugs with antiangiogenic and antiproliferative properties to the therapeutic armamentarium for HCC has prompted the design of clinical trials aimed at investigating the synergies between loco-regional and systemic treatments. The outcomes of these trials are eagerly awaited, because they have the potential to revolutionize the treatment of HCC. (HEPATOLOGY 2010;) [source]

    Radiofrequency ablation is justified for elderly patients with hepatocellular carcinoma

    HEPATOLOGY RESEARCH, Issue 10 2010
    Toru Ishikawa
    No abstract is available for this article. [source]

    Electrophysiologic and electrocardiographic characteristics of focal atrial tachycardia arising from superior tricuspid annulus

    J. X. Yin
    Summary Objectives:, This study describes the electrophysiologic and electrocardiographic characteristics of focal atrial tachycardia (AT) arising from superior tricuspid annulus in six (1.9%) patients of a consecutive series of 320 patients. Methods:, Six patients (mean age 42 22 years) with a mean cycle length of 326 ms of a consecutive series of 320 patients undergoing radiofrequency ablation for focal AT were mapped. Results:, During electrophysiologic study, tachycardia could be induced in five patients with programmed atrial extrastimuli while a spontaneous onset and offset with ,warm-up and cool-down' phenomenon was seen in the other patient. During tachycardia, P-wave morphology in Lead I, II, III and aVF was upright in all the six patients. The precordial leads were dominantly negative or isoelectric in V1,V2 and positive in V5,V6 with a transition at V3 or V4. Moreover, the tachycardia was sensitive to intravenous administration of adenosine triphosphate in five of six patients. Conclusions:, Radiofrequency ablation was performed successfully in all patients (mean 4.5 1.2 applications). No recurrence of AT was observed after a mean follow-up of 8 6 months. Thus, AT arising from superior tricuspid annulus is rare. Radiofrequency ablation of this kind of AT is safe and effective. [source]