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RF Catheter Ablation (rf + catheter_ablation)
Selected AbstractsLong-Term Follow-Up After Radiofrequency Catheter Ablation of Ventricular Tachycardia: A Successful Approach?JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2002ALIDA E. BORGER VAN DER BURG M.D. RF Catheter Ablation of VT.Introduction: Radiofrequency ablation (RFCA) of ventricular tachycardia (VT) is a potential curative treatment modality. We evaluated the results of RFCA in patients with VT. Methods and Results: One hundred fifty-one consecutive patients (122 men and 29 women; age 57 ± 16 years) with drug-refractory VT were treated. Underlying heart disease was ischemic heart disease in 89 (59%), arrhythmogenic right ventricular cardiomyopathy (ARVC) in 32 (21%), and idiopathic VT in 30 (20%; left ventricle in 9 [30%]; right ventricle in 21 [70%]). Ablation was performed using standard ablation techniques. Three hundred six different VTs were treated (cycle length 334 ± 87 msec, 2.0 ± 1.4 VTs per patient). Procedural success (noninducibility of VT after RFCA) was achieved in 126 (83%) patients (70 ischemic heart disease [79%]; 28 ARVC [88%]; 27 idiopathic VT [93%]). Procedure-related complications (< 48 hours) occurred in 11 (7%) patients: death 3 (2.0%), cerebrovascular accident 2 (1.3%), complete heart block 4 (2.6%), and pericardial effusion 3 (2.0%). Thirty-three (22%) patients received an implantable cardioverter defibrillator (because of hemodynamic unstable VT, failure of the procedure, or aborted sudden death). During follow-up (34 ± 11 months), VT recurrences occurred in 38 (26%) patients (recurrence rate: 19% in successfully ablated patients and 64% in nonsuccessfully ablated patients; P < 0.001). During follow-up, 12 (8%) patients died (heart failure 8, unknown cause 1, noncardiac cause 3). Conclusion: RFCA of VT can be performed with a high degree of success (83%). The long-term outcome of successfully ablated patients is promising, with a 75% relative risk reduction compared with nonsuccessfully ablated patients. During follow-up, only one patient died suddenly, supporting a selective ICD placement approach in patients with hemodynamically stable VT. [source] Electrocardiographic and Electrophysiologic Characteristics of Midseptal Accessory PathwaysJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2005SHIH-LING CHANG M.D. Background: The purpose of the present study was to investigate the electrocardiographic and electrophysiologic characteristics of right midseptal (RMS) and left midseptal (LMS) accessory pathways (APs), and to develop a stepwise algorithm to differentiate RMS from LMS APs. Methods and Results: From May 1989 to February 2004, 1591 patients with AP-mediated tachyarrhythmia underwent RF catheter ablation in this institution, and 38 (2.4%) patients had MS APs. The delta wave and precordial QRS transition during sinus rhythm, retrograde P wave during orthodromic tachycardia, and electrophysiologic characteristic and catheter ablation in 30 patients with RMS APs and 8 patients with LMS APs were analyzed. There was no significant difference in electrophysiologic characteristics and catheter ablation between RMS and LMS APs. The polarity of retrograde P wave during orthodromic tachycardia also showed no statistical difference between patients with RMS and LMS APs. The delta wave polarity was positive in leads I, aVL, and V3 to V6 in patients with RMS and LMS APs. Patients with LMS APs had a higher incidence of biphasic delta wave in lead V1 than patients with RMS APs (80% vs. 15%, P = 0.012). The distributions of precordial QRS transition were different between RMS APs (leads V2; n = 10, V3; n = 7 and V4; n = 3) and LMS APs (leads V1; n = 1 and V2; n = 4) (P = 0.03). The combination of a delta negative wave in lead V1 or precordial QRS transition in lead V3 or V4 had a sensitivity of 90%, specificity of 80%, positive predictive value of 95%, and negative predictive value of 66% in predicting an RMS AP. Conclusions: Delta wave polarity in lead V1 and precordial QRS transition may differentiate RMS and LMS APs. [source] Rapid Atrial Pacing: A Useful Technique During Slow Pathway AblationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2007LEONARDO LIBERMAN M.D. Background: Catheter ablation is the treatment of choice for atrioventricular nodal reentrant tachycardia (AVNRT) with a success rate of 95,98%. The appearance of junctional rhythm during radiofrequency (RF) application to the slow pathway has been consistently reported as a marker for the successful ablation of AVNRT. Ventriculoatrial (VA) conduction during junctional rhythm has been used by many as a surrogate marker of antegrade atrioventricular nodal (AVN) function. However, VA conduction may not be an accurate or consistent marker for antegrade AVN function and reliance on this marker may leave some patients at risk for antegrade AVN injury. Objective: The purpose of this study is to describe a technique to ensure normal antegrade AVN function during junctional rhythm at the time of RF catheter ablation of the slow pathway. Methods: Retrospective review of all patients less than 21 years old who underwent RF ablation for AVNRT at our institution from January 2002 to July 2005. During RF applications, immediately after junctional rhythm was demonstrated, RAP was performed to ensure normal antegrade AVN function. Postablation testing was performed to assess AVN function and tachycardia inducibility. Results: Fifty-eight patients underwent RF ablation of AVNRT during the study period. The mean age ± SD was 14 ± 3 years (range: 5,20 years). The weight was 53 ± 15 Kg (range: 19,89 Kg). The preablation Wenckebach cycle length was 397 ± 99 msec (range: 260,700 msec). Fifty-four patients had inducible typical AVNRT, and four patients had atypical tachycardia. The mean tachycardia cycle length ± SD was 323 ± 62 msec (range: 200,500 msec). Patients underwent of 8 ± 7 total RF applications (median: 7; range 1 to 34), for a total duration of 123 ± 118 seconds (median: 78 sec, range: 20,473 sec). Junctional tachycardia was observed in 52 of 54 patients. RAP was initiated during junctional rhythm in all patients. No patient developed any degree of transient or permanent AVN block. Following ablation, the Wenckebach cycle length decreased to 364 ± 65 msec (P < 0.01). Acutely successful RF catheter ablation was obtained in 56 of 58 patients (96%). Conclusion: Rapid atrial pacing during radiofrequency catheter ablation of the slow pathway is a safe alternative approach to ensure normal AVN function. [source] Electrophysiologic Characteristics and Radiofrequency Catheter Ablation in Children with Wolff-Parkinson-White SyndromePACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2006PI-CHANG LEE Background: The majority of cardiac arrhythmias in children are supraventricular tachycardia, which is mainly related to an accessory pathway (AP)-mediated reentry mechanism. The investigation for Wolff-Parkinson-White (WPW) syndrome in adults is numerous, but there is only limited information for children. This study was designed to evaluate the specific electrophysiologic characteristics and the outcome of radiofrequency (RF) catheter ablation in children with WPW syndrome. Methods: From December 1989 to August 2005, a total of 142 children and 1,219 adults with atrioventricular reentrant tachycardia (AVRT) who underwent ablation at our institution were included. We compared the clinical and electrophysiologic characteristics between children and adults with WPW syndrome. Results: The incidence of intermittent WPW syndrome was higher in children (7% vs 3%, P=0.025). There was a higher occurrence of rapid atrial pacing needed to induce tachycardia in children (67% vs 53%, P=0.02). However, atrial fibrillation (AF) occurred more commonly in adult patients (28% vs 16%, P = 0.003). The pediatric patients had a higher incidence of multiple pathways (5% vs 1%, P < 0.001). Both the onset and duration of symptoms were significantly shorter in the pediatric patients. The antegrade 1:1 AP conduction pacing cycle length (CL) and antegrade AP effective refractory period (ERP) in children were much shorter than those in adults with manifest WPW syndrome. Furthermore, the retrograde 1:1 AP conduction pacing CL and retrograde AP ERP in children were also shorter than those in adults. The antegrade 1:1 atrioventricular (AV) node conduction pacing CL, AV nodal ERP, and the CL of the tachycardia were all shorter in the pediatric patients. Conclusion: This study demonstrated the difference in the electrophysiologic characteristics of APs and the AV node between pediatric and adult patients. RF catheter ablation was a safe and effective method to manage children with WPW syndrome. [source] Is the Fascicle of Left Bundle Branch Involved in the Reentrant Circuit of Verapamil-Sensitive Idiopathic Left Ventricular Tachycardia?PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 10 2003JEN-YUAN KUO The exact reentrant circuit of the verapamil-sensitive idiopathic left VT with a RBBB configuration remains unclear. Furthermore, if the fascicle of left bundle branch is involved in the reentrant circuit has not been well studied. Forty-nine patients with verapamil-sensitive idiopathic left VT underwent electrophysiological study and RF catheter ablation. Group I included 11 patients (10 men, 1 woman; mean age 25 ± 8 years) with left anterior fascicular block (4 patients), or left posterior fascicular block (7 patients) during sinus rhythm. Group II included 38 patients (29 men, 9 women; mean age 35 ± 16 years) without fascicular block during sinus rhythm. Duration of QRS complex during sinus rhythm before RF catheter ablation in group I patients was significant longer than that of group II patients (104 ± 12 vs 95 ± 11 ms, respectively, P = 0.02). Duration of QRS complex during VT was similar between group I and group II patients (141 ± 13 vs 140 ± 14 ms, respectively, P = 0.78). Transitional zones of QRS complexes in the precordial leads during VT were similar between group I and group II patients. After ablation, the QRS duration did not prolong in group I or group II patients (104 ± 11 vs 95 ± 10 ms, P = 0.02); fascicular block did not occur in group II patients. Duration and transitional zone of QRS complex during VT were similar between the two groups, and new fascicular block did not occur after ablation. These findings suggest the fascicle of left bundle branch may be not involved in the antegrade limb of reentry circuit in idiopathic left VT. (PACE 2003; 26:1986,1992) [source] Radiation Exposure During Radiofrequency Catheter Ablation for Atrial FibrillationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1p2 2003LAURENT MACLE MACLE, L., et al.: Radiation Exposure During Radiofrequency Catheter Ablation for Atrial Fibrillation.RF catheter ablation of paroxysmal atrial fibrillation (PAF) is associated with prolonged fluoroscopy. The procedural duration and fluoroscopic exposure to patients and medical staff were recorded and compared among 43 ablation procedures for PAF, 20 for common atrial flutter, and 16 for accessory pathways. Patient radiation exposure was measured by dosimeters placed over the xyphoid, while that of physicians and nurses was measured by dosimeters placed outside and inside the lead apron. The mean fluoroscopy time was57 ± 30minutes for PAF,20 ± 10minutes for common flutter, and22 ± 21minutes for accessory pathway ablation. The patient median radiation exposure was 1110,Sv for PAF, compared with 500 ,Sv for common flutter and 560 ,Sv for accessory pathway ablation (P < 0.01). The median radiation exposure to physician and nurse inside the lead apron were, respectively, 2 ,Sv and 3 ,Sv for PAF, 1 ,Sv and 2 ,Sv for common flutter, and <0.5 ,Sv and 3 ,Sv for accessory pathway ablations. RF catheter ablation for PAF was associated with prolonged fluoroscopy times and a twofold higher radiation exposure to the patient and physician compared with other ablation procedures. Assuming 300 procedures/year, radiation exposure to the medical staff was below the upper recommended annual dose limit. (PACE 2003; 26[Pt. II]:288,291) [source] Successful Pediatric Stenting of a Nonthrombotic Coronary Occlusion as a Complication of Radiofrequency Catheter AblationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 6 2001GUNNAR G. STROBEL STROBEL, G.G., et al.: Successful Pediatric Stenting of a Nonthrombotic Coronary Occlusion as a Complication of Radiofrequency Catheter Ablation. This is a case of a right coronary artery occlusion complicating a RF catheter ablation of a posteroseptal accessory connection in an 8-year-old boy. After multiple balloon angioplasty attempts in the occluded vessel, only transient patency was achieved. The occlusion was successfully treated with placement of an intracoronary stent. [source] When Should Heparin Preferably Be Administered During Radiofrequency Catheter Ablation?PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2001OLE-GUNNAR ANFINSEN ANFINSEN, O.-G., et al.: When Should Heparin Preferably be Administered During Radiofrequency Catheter Ablation? RF catheter ablation is complicated by thromboembolism in about 1% of patients. Limited knowledge exists concerning when and how to use anticoagulation or antithrombotic treatment. We studied the activation of coagulation (prothrombin fragment 1 + 2 [PF1 + 2] and D-dimer), platelets (,-thromboglobulin [,-TG]) and fibrinolysis (plasmin-antiplasmin complexes [PAP]) during RF ablation of accessory pathways in 30 patients. They were randomized to receive heparin (100 IU/kg, intravenously) (1) immediately after introduction of the femoral venous sheaths (group I) or (2) after the initial electrophysiological study, prior to the delivery of RF current (groups II and III). Group II additionally received saline irrigation of all femoral sheaths. After the initial bolus, 1,000 IU of heparin was supplied hourly in all groups. Within groups II and III, median plasma values of PF1 + 2 and ,-TG more than tripled (P , 0.007) during the diagnostic study and gradually declined during heparin administration despite RF current delivery. Median D-dimer tripled (P = 0.005) and PAP doubled (NS) before heparin administration; then both remained around the upper reference values. In the early heparin group, however, PF1 + 2, Ddimer, and PAP did not rise at all, and ,-TG showed only a slight increase towards the end of the procedure. The differences between group I versus groups II and III were statistically significant prior to the first RF current delivery (PF1 + 2, D-dimer, and ,-TG) and by the end of the procedure (PF1 + 2, D-dimer, and PAP). In conclusion, "late" heparin administration allows hemostatic activation during the initial catheterization and diagnostic study. By administering intravenous heparin immediately after introduction of the venous sheaths, hemostatic activation is significantly decreased. Saline irrigation of the venous sheaths added nothing to late heparin administration. [source] | ||||||||||