Multiple Accessory Pathways Research Articles

Recurrence rate after accessory pathway ablation.

To evaluate characteristics of patients and accessory pathways as well as additional technical factors involved in the reappearance of accessory pathway conduction after successful ablation. Analysis of recurrences after radiofrequency ablation. 163 consecutive patients with 167 accessory pathways. 97 men and 66 women with a mean (SD) age of 36 (14) range (11 to 75) years. After a mean (SD) follow up of 14 (7) range (2 to 27) months, conduction recurred in 13 out of 167 (7.8%) accessory pathways. The initial manifestation of recurrence was circus movement tachycardia in 7 patients and reappearance of delta waves on a 12 lead electrocardiogram in 6 patients. The interval to the return of accessory pathway conduction ranged from 3 hours to 90 days. Age, sex, presence of multiple accessory pathways, criteria to determine the target ablation site, number and duration of radiofrequency applications, and cumulative energy did not significantly differ between the groups with recurrence and without. Recurrence was less common with concealed accessory pathways (2/44) than with overt accessory pathways (11/110). The difference was not significant. The only variable to influence the recurrences in this study group was the location of the accessory pathway. Reappearance of conduction through right sided accessory pathways occurred significantly more often than through left sided ones (8/40 v 5/114, P = 0.01). After radiofrequency ablation the recurrence rate of accessory pathways is low and there are no predictors of the risk of reappearance of conduction apart from the right sided location of the accessory pathway.

Radiofrequency catheter ablation of septal accessory atrioventricular pathways.

Septal accessory atrioventricular pathways are recognised as being more difficult to ablate than pathways in other locations. This paper describes an experience of 48 consecutive patients with septal accessory pathways who had catheter ablation with radiofrequency current. There were 28 male and 20 female patients, mean (SD) age 35 (17). 43 patients had a single accessory pathway and 5 patients had multiple accessory pathways. Pre-excitation was present in 37 patients, and 11 patients had concealed accessory pathways. 21 patients had had a previous electrophysiological study. Catheter ablation was undertaken with radiofrequency current delivered by a standard unipolar technique or by delivery of current across the septum (the bipolar technique). The median total procedure time was 167 (83) minutes including a 30-40 minute observation period after the abolition of conduction by the accessory pathway. The median total fluoroscopic time was 56 (30) minutes. 42 (88%) out of 48 patients had successful ablation of the pathway during the first session. In the six patients in whom the procedure failed, five had a midseptal pathway and one had a right anteroseptal pathway. A second attempt at ablation was made in two patients and succeeded in both. In total, 49 accessory pathways were successfully ablated in 44 (92%) out of 48 patients. The bipolar technique was used in 11 patients and succeeded in 10 patients. Standard unipolar current delivery had previously failed in seven of the 11 patients. Complications developed in two patients with a mid septal pathway (one with complete atrioventricular block and the other with a small pericardial effusion). Radiofrequency catheter ablation of septal accessory pathways is efficacious and safe. The procedure time can be shortened and success rate can be increased after improvement of the technique--that is, consideration of a bipolar approach for energy delivery in difficult cases.

Multiple accessory pathways in the permanent form of junctional reciprocating tachycardia

The permanent form of junctional reciprocating tachycardia (PJRT) has been successfully eliminated by ablation of the accessory pathway responsible for the tachycardia. The coexistence of multiple accessory pathways responsible for different, long RP-interval tachycardias was not documented previously. Five patients with PJRT underwent radiofrequency catheter ablation of accessory pathways. Three of 5 patients had 2 accessory pathways each: 1 had 2 left free wall accessory pathways, another had a right posterior free wall and right posteroseptal pathway, whereas the third had 2 right posteroseptal pathways approximately 1 cm apart. The remaining 2 patients each had 1 right posteroseptal accessory pathway. Seven of 8 pathways were successfully ablated with a median of 3 radiofrequency pulses. No patient developed complications. Peak serum creatine kinase ranged from 131 to 311 IU/liter, with peak MB fraction 7 to 17 IU/liter, or 5 to 11%. Follow-up electrophysiologic study, 29 to 70 days after ablation, revealed no inducible tachycardia and no evidence of accessory pathway conduction, except for the 1 pathway not ablated. All patients remained asymptomatic 17 to 29 months after ablation. Thus, patients with PJRT can have several accessory pathways that can be safely and effectively eliminated with radiofrequency catheter ablation.

Catheter ablation of accessory pathways in children

The efficacy and safety of catheter ablation of accessory pathways (AP) was studied in 79 children (age, 4-16 years), using DC shocks (n = 25) or radiofrequency energy (n = 54). All patients had documented arrhythmias including ventricular fibrillation in four. Organic heart disease was present in four patients. AP locations were left lateral (n = 36), posteroseptal (n = 36), right lateral (n = 8), Mahaim fibres (n = 2) and right anteroseptal (n = 6). Seven patients had multiple AP. One patient had a preexcitation which appeared secondary to an atrio-infundibular connection (Fontan procedure). The ablation site of concealed or overt AP was identified by retrograde or anterograde conduction mapping, respectively. A mean of 2.6 +/- 1 cathodal shocks (80-160 J) was delivered to 25 patients over 29 sessions, resulting in initial AP ablation in all. Fulguration was uncomplicated in all except in one patient (4%) who developed a secondary complete AV block post-ablation. During a follow-up period of 30-69 months, intermittent preexcitation recurred in two asymptomatic patients, but no significant tachycardia was inducible at late electrophysiological study, including under isoproterenol infusion. Radiofrequency energy was applied to 54 patients during 62 sessions, using 20-40 watts for 30-60 s. AP ablation was initially achieved in all patients using a median of three impulses, without significant immediate side-effects. Two patients (4%) developed a short episode of blurred vision possibly due to a microembolism. After discharge, the follow-up period was 10 +/- 5 months (range 1 to 24). All patients but one (98%) were asymptomatic without any drug therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

A case of Wolff-Parkinson-White syndrome with various tachycardias due to multiple accessory pathways and dual atrioventricular nodal pathways

A case of Wolff-Parkinson-White syndrome with various tachycardias due to multiple accessory pathways and dual atrioventricular nodal pathways

A case of successful radiofrequency catheter ablation of right sided multiple accessory pathway in Wolff-Parkinson-White syndrome with Ebstein's anomaly

A case of successful radiofrequency catheter ablation of right sided multiple accessory pathway in Wolff-Parkinson-White syndrome with Ebstein's anomaly

Effect of pregnancy on paroxysmal supraventricular tachycardia

more detailed study is undertaken. In the present study, 24% (6 of 25) of patients had either dual AV node pathways or multiple accessory pathways. In such cases, the initial use of an abbreviated protocol may actually prolong the procedure. One additional point merits consideration. In our study, tachycardia was not induced in 3 of 12 patients in the abbreviated protocol, whereas all patients had tachycardia when atrial and ventricular extrastimuli were included. Contirmation that the observed pathway(s) participate in the clinical tachycardia provides the best proof that ablation, with its attendant risks and expenses, is actually merited.

Surgical treatment of the Wolff-Parkinson-White syndrome--experiences in 120 patients.

Since January 1984, 120 patients (78 male, 42 female; aged 3 to 66 years) with the Wolff-Parkinson-White (WPW) syndrome have been operated upon. The indication for surgery was documented recurrent, paroxysmal tachycardia refractory to medical treatment in 118 cases. Twenty-two patients (18%) had additional heart disease. One hundred and twenty patients had a total of 140 accessory pathways (AP). AP were localized at the left free wall in 63% (87 AP), at the right free wall in 24% (35 AP), and septally in 13% (18 AP). Sixteen patients (13%) had multiple AP (12 patients had two and four patients had three AP), 124 AP were known pre-operatively (88%), 133 were localized intra-operatively (94%) and seven were diagnosed during re-operation (6%). Surgery in 28 patients with left lateral AP was via the epicardial approach and the endocardial approach in 59. Of 15 patients with right lateral AP, the surgical approach was epicardial in two and transmural in 13. A cryosurgery was also used in 117 patients. Fifteen patients suffered recurrences, in 12 of whom repeat surgery was required. One hundred and thirty-six AP (97%) were dissected successfully, of which 14 (10%) were ablated during re-operation. All patients survived the initial operation, but two patients died after re-operation. One patient is pacer-dependent due to persisting postoperative atrioventricular (AV) block. We conclude that surgical dissection of accessory pathways can be offered as an alternative to non-surgical treatment modes, at a low risk and with a high success rate.

Radiofrequency ablation in multiple accessory pathways and the physiologic implications

The presence of multiple accessory pathways was noted in 24 of 210 consecutive patients (12 males and 12 females aged 15 to 77 years [mean ± SD 43 ± 16]) with the Wolff-Parkinson-White syndrome who underwent electrophysiologic study and radiofrequency ablation. Six had 3 and 18 had 2 accessory pathways. There were 25 manifest and 29 concealed accessory pathways. The location of the accessory pathways was in the left free wall in 22, the right free wall in 17, the left posterior portion of the ventricular septum in 8, the right posterior portion of the ventricular septum in 6, and the midseptum in 1. The success rate of accessory pathway ablation and the fluoroscopic time in these 24 patients with multiple accessory pathways were 89% and 78 ± 66 minutes, respectively, whereas they were 98% (p < 0.01) and 36 ± 37 minutes (p = 0.01) in the 186 patients with a single accessory pathway. The mean applications, the power level of the radiofrequency current and the application duration in these 24 patients were 21 ± 22, 30 ± 3 W, and 27 ± 10 seconds, respectively. In the 186 patients with a single accessory pathway, they were 9 ± 12 applications (p = 0.02), 30 ± 4 W (p = NS) and 26 ± 9 seconds (p = NS), respectively. Seventeen of the 24 patients had a follow-up electrophysiologic study 89 ± 40 days after ablation, and 2 (12%) had resumption of a right and left accessory pathway conduction. In conclusion, patients with multiple accessory pathways can be treated by radiofrequency ablation in a single session with a high success rate, although slightly less than that in patients with a single accessory pathway.

Reappraisal of radiofrequency ablation of multiple accessory pathways

Complete electrophysiologic study and radiofrequency ablation were performed in 145 consecutive patients with Wolff-Parkinson-White syndrome. Presence of multiple accessory atrioventricular pathways was documented in 20 patients (13.8%); 17 had two, two had three, and one had four accessory pathways. Location of accessory pathways was posteroseptal in 18, left free wall in 15, right free wall in nine, and right midseptal in two. Of the 44 pathways, 36 were found during baseline electrophysiologic study and eight were found after successful ablation of the initially attempted pathways. After delivering 20 ± 23 pulses (per patient) of radiofrequency energy (37 ± 6 W, 70 ± 30 seconds), 43 accessory pathways were ablated successfully without complications. Duration of the procedure (4.5 ± 1.7 vs 3.7 ± 1.6 hours, p < 0.05) and radiation exposure time (53 ± 30 vs 38 ± 18 minutes, p < 0.05) were longer in patients with multiple pathways, whereas the success rate (95% vs 95%, p > 0.05) and incidence of recurrent conduction (11% vs 11%, p > 0.05) were similar in patients with single or multiple accessory pathways. These findings confirmed that multiple accessory pathways were common in patients with Wolff-Parkinson-White syndrome, and these pathways could be ablated successfully by radiofrequency energy with a success rate comparable to that of a single accessory pathway.

Multiple Concealed Accessory Pathways Associate with Antegrade Triple AV Nodal Pathways and Catheter Ablation

Multiple Concealed Accessory Pathways Associate with Antegrade Triple AV Nodal Pathways and Catheter Ablation

Usefulness of predischarge electrophysiologic study in predicting late outcome after surgical ablation of the accessory pathway in the Wolff-Parkinson-White syndrome

A predischarge electrophysiologic study was performed in 113 patients with the Wolff-Parkinson-White (WPW) syndrome who had undergone surgical ablation of the accessory pathway. The study was performed 5 to 20 (mean 10 ± 3) days after surgery. There were 82 male and 31 female patients (aged 4 to 58 years, mean 36 ± 13). Sixtyone patients (54%) had manifest, 52 (46%) had concealed and 12 (11%) had multiple accessory pathways. All but 1 patient had atrioventricular reentrant tachycardia incorporating single or multiple accessory pathways during the control electrophysiologic study. The accessory pathways were located in the left ventricular free wall in 60% of cases, right ventricular free wall in 22%, posteroseptum in 13%, and anteroseptum in 5%. The predischarge electrophysiologic study showed that the accessory pathway was capable of anterograde and retrograde conductions in 4 patients (all with manifest WPW syndrome). Four patients showed induction of supraventricular tachycardia, including 2 with atrioventricular reentrant tachycardia, and 2 with atrioventricular nodal reentrant tachycardia. Recurrence of supraventricular tachycardia was noted in 5 patients during a follow-up of 28 ± 26 months. Of these 5 patients, 2 had inducible and 3 had no inducible supraventricular tachycardia during the predischarge electrophysiologic study. Thus, the predischarge electrophysiologic study could predict late outcome with recurrence of preexcitation or supraventricular tachycardia in patients who had undergone surgical ablation of the accessory pathway with an overall predictive accuracy of 95% (107 of 113 patients), negative predictive value of 96% (103 of 107), and positive predictive value of 67% (4 of 6).

New observations on atrial fibrillation before and after surgical treatment in patients with the Wolff-Parkinson-White syndrome

The records of 342 patients who received surgical treatment for the Wolff-Parkinson-White syndrome between 1968 and 1986 were reviewed to evaluate the characteristics of atrial fibrillation. The patients were classified into two groups according to the presence (n = 166) or absence (n = 176) of documented episodes of atrial fibrillation preoperatively. The mean follow-up duration was 6 years (range 2 to 20).As compared with reports based on smaller patient groups and shorter follow-up, the study revealed several new findings. 1) During follow-up, nine patients in the atrial fibrillation group developed recurrent atrial fibrillation after a successful operation; five of these nine patients did not have associated heart disease. 2) All three patients with a history of atrial fibrillation and an accessory pathway conducting in the anterograde direction only had a successful surgical procedure and no postoperative atrial fibrillation. 3) The cycle length of atrioventricular (AV) reciprocating tachycardia was significantly shorter in the atrial fibrillation group (304 ± 42 ms, mean ± SD) than in the no-atrial fibrillation group (321 ± 54 ms, p < 0.005), and the cycle length of AV reciprocating tachycardia that degenerated into atrial fibrillation (289 ± 26 ms) was shorter than that for the AV reciprocating tachycardia without subsequent atrial fibrillation (316 ± 51 ms, p < 0.005).4) Sustained atrial fibrillation was induced in 30% of patients without a history of atrial fibrillation. 5) Atrial fibrillation occurred in four patients with an accessory pathway that conducted only in the retrograde direction. 6) The prevalence of multiple accessory pathways was equal in the group with (20 of 166) and without (29 of 176) atrial fibrillation.It is concluded that in most patients, conversion of rapid reciprocating tachycardia is a likely mechanism of spontaneous atrial fibrillation. However, the probability that other mechanisms may contribute to the occurrence of atrial fibrillation in patients with the Wolff-Parkinson-White syndrome is suggested by data from three patients with an accessory pathway that conducted only in the anterograde direction and from five patients who had recurrent atrial fibrillation despite a successful surgical outcome. The data suggest that the surgical procedure does not result in late occurrence of atrial fibrillation.

Radiofrequency Catheter Ablation of Three Accessory Pathways in a Single Session

Radiofrequency Ablation of Multiple Accessory Pathways. A 19‐year‐old patient is described having three accessory atrioventricular pathways. All three pathways were ablated using radiofrequency current in a single electrophysiologic investigation. (J Cardiovasc Electrophysiol, Vol. 3, pp. 141–149, April 1992)

Low Energy Direct Current Ablation in Patients with the Wolff-Parkinson-White Syndrome: Clinical Outcome According to Accessory Pathway Location

Forty-five patients with the Wolff-Parkinson-White syndrome underwent direct current (DC) ablation using a low energy power source (Cardiac Recorders). Anodal shocks of 10-40 joules were given to either a 6 French quadripolar catheter (Bard), a 7 French bipolar contoured catheter (Bard), or a 7 French deflectable catheter with a 4-mm distal electrode (Mansfield). The indifferent electrode consisted of a large patch that was positioned under the left scapula. There were 26 males and 19 females, with a mean age of 34 years (range 9-67). Accessory pathways were located in the left free wall in 30 patients (67%) and were posteroseptal in 15 patients (33%). The shortest ventriculoatrial interval during mapping (89 +/- 21 msec), the mean cumulative amount of energy per patient (322 +/- 283 joules), and the mean CK-MB rise (45 +/- 30 units, normal 0-30 units) were not significantly different between both groups. Ablation was successful in 29/30 patients (97%) with a left free-wall accessory pathway, and in 13/15 patients (87%) with a posteroseptal accessory pathway. All three patients with failure of ablation had multiple accessory pathways, and two of these patients had Ebstein's anomaly. Patients with left free-wall and posteroseptal accessory pathways, respectively, differed significantly in terms of: total session time (4.1 +/- 1 hours vs 5.3 +/- 1.3, p = 0.0001), total procedure time for ablation (2.6 +/- 0.8 hours vs 3.2 +/- 1.2, P = 0.02), and fluoroscopy time (46 +/- 24 min vs 64 +/- 29, P = 0.006). In 13 patients (29%) with a concealed accessory pathway, these variables were not significantly different from patients with overt preexcitation.(ABSTRACT TRUNCATED AT 250 WORDS)

Role of concealed and supernormal conductions during atrial fibrillation in the preexcitation syndrome

The hypothesis that retrograde concealed and anterograde supernormal conductions over the accessory pathway are determinants of anterograde accessory pathway conduction during atrial fibrillation (AF) was prospectively tested. For 17 patients during AF, 90 ± 13 (mean ± standard deviation) consecutive beats were analyzed for morphology and VV interval preceding each QRS complex. In 15 patients with both preexcited and normal QRS complexes, after normal complexes, the cycle length preceding the first preexcited QRS complex was 389 ± 69 ms, which was longer than the average cycle length of consecutive preexcited complexes (325 ± 55 ms; p = 0.001). The mean difference was 61 ± 53 ms. After preexcited QRS complexes, the cycle length preceding the first normal QRS complex averaged 423 ± 65 ms, which was significantly longer than the average cycle length of 345 ± 47 ms between consecutively conducted normal QRS complexes (p < 0.001). The mean difference was 86 ± 45 ms. These findings suggest retrograde concealed conduction of normally conducted QRS complexes to the accessory pathway can affect anterograde conduction over the accessory pathway, and vice versa. In 2 patients with multiple accessory pathways, 1 accessory pathway conducted only after short preceding cycle lengths (355 to 360 and 181 to 185 ms), which was consistent with supernormal conduction. In conclusion, retrograde concealed conduction to the accessory pathway and anterograde supernormal accessory pathway conduction are factors that, in part, determine accessory pathway conduction during AF.

Current treatment for Wolff-Parkinson-White syndrome: Results and surgical implications

From July 1986 to January 1991, 123 patients with Wolff-Parkinson-White syndrome underwent operation for ablation of aberrant conduction pathways. There were 85 male and 38 female patients ranging in age from 11 months to 68 years. Associated anomalies included Ebstein's anomaly, sudden death syndrome, coronary artery disease, cardiomyopathy, abdominal aortic aneurysm, neurofibromatosis, other arrhythmias, or other complex congenital heart disease. Forty-one patients had multiple accessory pathways. Operative results showed a 7% initial failure rate, which dropped to 3% after reoperation. One patient had undergone previous operation for Wolff-Parkinson-White syndrome at another institution. Procedures performed concomitantly included mitral or tricuspid valve repair or replacement (6), right ventricular conduit replacement, subaortic resection, Fontan repair, corrected transposition repair, coronary artery bypass, and placement of an automatic internal cardioverter defibrillator. There was no operative mortality. Late follow-up is 27 ± 16 months, and complications included mitral regurgitation and myocardial infarction. By comparison, in the last 12 months 124 patients with the Wolff-Parkinson-White syndrome underwent catheter ablation using radiofrequency current. There were 9 patients with multiple pathways. One hundred twelve patients (90%) had all accessory atrioventricular connections ablated and have remained free of symptomatic tachycardia. There have been 12 failures (10%), of which 5 have had operation and 7 are being treated medically. Mean follow-up is 7 ± 5 months, and complications included circumflex coronary artery occlusion, excessive bleeding, valve perforation, and cerebral vascular accident. Both procedures offer excellent success with low morbidity. Although continued late follow-up is mandatory to assess the results of radiofrequency ablation, the early results suggest that operation for Wolff-Parkinson-White syndrome may become indicated for radiofrequency ablation failure, multiple pathways, or when additional procedures are required.

Predictive accuracy of electrophysiologic localization of accessory pathways

Operative ablation of accessory pathways depends critically on preoperative localization when technical limitations preclude complete intraoperative mapping. To assess the accuracy of localization, 345 patients undergoing operative ablation were studied 316 (91.6%) had a single accessory pathway and 29 (8.4%) had multiple accessory pathways. The electrophysiologic study was diagnostically complete and accurate in 294 patients (93%) with a single accessory pathway and 19 (61%) with multiple accessory pathways.A left lateral accessory pathway was most accurately localized with excellent sensitivity (99%) and positive predictive value (98.5%). Diagnostic errors occurred in 33 patients because of 1) incorrect localization (n = 16), 2) failure to detect a second pathway (n = 9), and 3) diagnosis of a second pathway not verified intraoperatively (n = 8). Multiple pathways were more prevalent in the group with errors (33.3% vs. 5.8%, p = 0.0001), as were unidirectional pathways (48.5% vs. 24.3%, p = 0.003).It is concluded that preoperative localization of accessory pathways is sufficiently accurate to allow intraoperative mapping to be brief and focused.

Operations for Wolff-Parkinson-White syndrome

Forty-six patients with symptomatic tachycardia underwent operations to divide 55 atrioventricular accessory pathways. Mean age was 29 years (range 11 to 63). Ten patients (22%) had associated cardiac disease, including two with a congenital diverticulum of the coronary sinus and six (13%) who had concomitant surgical procedures. A bipolar hand-held electrode was used in 22 operations, and simultaneous multisite mapping in the last 24 operations. Ten patients (22%) had multiple accessory pathways. A modified endocardial approach was used. The overall patient success rate was 93% with 91% to 93% of accessory pathways successfully divided. The perioperative morbidity was 17%. There were two reoperations. There were no early or late deaths. Patients have been followed up for a mean of 16 months. There were five recurrences of preexcitation (two early, three late). Two of these patients (both with a congenital diverticulum of the coronary sinus) had reoperation. One patient had late recurrence of atrial fibrillation. Operation for the Wolff-Parkinson-White syndrome has a high probability of success with a low operative risk.

Multiple accessory pathways in the Wolff-Parkinson-White syndrome as a risk factor for ventricular fibrillation

Ventricular fibrillation (VF) after atrial fibrillation is the mechanism of sudden death in most patients with Wolff-Parkinson-White (WPW) syndrome. 1–3 Initial data from Duke University 1 suggested that patients who had VF had a shortest RR interval between preexcited beats during atrial fibrillation <250 ms. The use of the shortest RR interval during atrial fibrillation in predicting sudden death prospectively is, however, limited by its low positive predictive value. 4 Several studies 1,5 have also noted the increased frequency of multiple accessory pathways in VF patients with WPW syndrome although other investigators 6 suggested that this was not the case. We sought to determine whether VF occurs more frequently in patients with multiple accessory pathways and whether multiple pathways may be considered as an additional risk factor for this complication.