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Multiple accessory pathways in patients with the Wolff-Parkinson-White syndrome are infrequent and are associated with a higher risk of ventricular fibrillation. We present an exceptional case of a patient with four accessory pathways with anterograde conduction and a fasciculo-ventricular fiber in whom we performed a radiofrequency ablation. A 20 year old healthy male patient was seen at the emergency room after suffering syncope. The electrocardiogram showed atrial fibrillation with wide QRS complex suggestive of preexcitation. The electrophysiologic study demonstrated the presence of four atrio-ventricular accessory pathways with antegrade conduction (left lateral, right posteroseptal, right midseptal and right posterolateral). After ablation of the fourth accessory pathway, the electrocardiogram showed a persistent delta wave with a short HV interval. Atrial stimulation demonstrated decremental conduction, progressive lengthening of the AH interval and no modification in the HV interval nor in the preexcitation pattern, suggestive of the presence of a fasciculo-ventricular fiber. This exceptional case report is demonstrative of the complexity of the Wolff-Parkinson-White syndrome, and the feasibility and efficacy of radiofrequency catheter ablation in a single procedure.

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INTRODUCTION: The aim of this study was to assess the long term results (minimum of 3 years) of radiofrequency catheter ablation in patients with common (slow-fast) atrioventricular nodal reentrant tachycardia. PATIENTS AND METHODS: Sixty consecutive patients (mean age 56 +/- 16 years, range 14 to 83, 16 men and 44 women) underwent slow pathway (n = 51, Group A) or fast pathway (n = 9, Group B) radiofrequency catheter ablation between January 1992 and March 1994. All patients were followed at 1, 3, 6 and 12 months after ablation with serial examinations and electrocardiograms and the last follow-up was made on April 1997. RESULTS: During a mean follow-up period of 48 +/- 7 months (range 38 to 63) all evaluated patients remained asymptomatic. Eight recurrences were observed at a mean of 1 +/- 2 months (range, 0.5 to 7) after a successful ablation procedure. A second procedure was effective in eliminating the dual atrioventricular nodal pathway in each of them. In Group A patients, the pre-ablation PR interval, at 12 months after ablation and at last follow-up were 122 +/- 11, 124 +/- 13 and 124 +/- 15 ms, respectively. In Group B patients, the pre-ablation PR interval, at 12 months after ablation and at last follow-up were 130 +/- 24, 200 +/- 12, 200 +/- 24 ms, respectively. No significant atrioventricular conduction disturbances in any patient were observed. One patient developed a new onset left bundle branch block and 4 patients died of noncardiac causes. CONCLUSIONS: In patients with atrioventricular nodal reentrant tachycardia, radiofrequency catheter ablation is a safe and effective therapy, with substantial good results that persist during long term follow-up, with a low recurrence rate and without complications during short and long term outcome.

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OBJECTIVES: This study sought to determine the long-term follow-up, safety and efficacy of radiofrequency catheter ablation in patients with the permanent form of junctional reciprocating tachycardia. We assessed the reversibility of tachycardia-related left ventricular dysfunction and we detailed the location and electrophysiologic characteristics of these atrioventricular decremental pathways. BACKGROUND: Permanent junctional reciprocating tachycardia is an infrequent form on reciprocating tachycardia, commonly incessant and usually drug-refractory. The electrocardiographic hallmarks include an RP interval > PR with inverted P waves in leads II, III, aVF and V3-V6. During tachycardia, retrograde ventriculo-atrial conduction occurs over an accessory pathway with decremental conduction properties, located predominantly in the posteroseptal zone. It is known that long lasting and incessant tachycardia may result in tachycardia-related severe ventricular dysfunction, the so called tachycardiomyopathy. PATIENTS AND METHODS: We included 24 patients (9 males, 15 females; mean age 42 +/- 22 years) with the diagnosis of permanent junctional reciprocating tachycardia at electrophysiologic study. Six patients had tachycardia-related left ventricular dysfunction. Radiofrequency energy was delivered at the site of earliest retrograde atrial activation during reciprocating tachycardia (n = 22) or ventricular pacing (n = 2). All patients were followed at the outpatient clinic and serial echocardiograms were performed in those who presented depressed left ventricular function. RESULTS: Radiofrequency catheter ablation was performed in 24 decremental accessory pathways. Earliest retrograde atrial activation was right posteroseptal in 22 patients (92%), right midseptal in 1 (4%) and right posterolateral in 1 (4%). Twenty-three accessory pathways were successfully ablated with a mean of 5 +/- 3 (median, 4) radiofrequency applications of a mean duration of 48 +/- 13 s. Only the midseptal accessory pathway could not be ablated. After a mean follow-up of 21 +/- 16 months (median, 15; range 2 to 64) 22 patients remain asymptomatic. There were recurrences in 4 patients after the initial successful ablation (three during the first month and one during the second month after the procedure), two were ablated in a second ablation procedure, one patient required a third procedure and one required a fourth. All patients with left ventricular dysfunction experienced an improvement after ablation. Mean preablation left ventricular ejection fraction in patients with tachycardiomyopathy was 28 +/- 6% (median, 27) and raised to 51 +/- 16% (median, 47) after ablation (p < 0.02). CONCLUSIONS: Our study supports the concept that radiofrequency catheter ablation is a safe and useful treatment for patients with permanent junctional reciprocating tachycardia. Radiofrequency current should be the treatment of choice in these patients because this arrhythmia is usually drug-refractory. The majority of accessory pathways with decremental conduction properties are localized in the posteroseptal zone. Cessation of the arrhythmia after successful ablation results in recovery of left ventricular dysfunction.

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INTRODUCTION: Postoperative analgesia is insufficiently done due, among others, to the undesirable effects of analgesic agents. OBJECTIVE: The aim of this study was to analyze the effects of the simultaneous administration of opiates (meperidine) and AINES (lysine acetylsalicylate, ASL). MATERIAL AND METHODS: We studied 160 patients during the immediate postoperative phase. All of them underwent programmed surgery with the same general anesthetic technique. Patients were allocated into 8 groups of treatment: A) ASL 900 mg and 1.800 mg/8 h, B) ASL 900 mg and 3.600 mg/8 h, C) ASL 900 mg and meperidine 100 mg/8 h, D) ASL 900 mg and 1.800 mg/8 h together with meperidine 100 mg/8 h, E) meperidine 50 mg and ASL 1.800 mg/8 h, F) meperidine 50 mg and ASL 3.600 mg/8 h, G) meperidine 50 mg and 100 mg/8 h, and H) meperidine 50 mg and 100 mg/8 h together with ASL 1.800 mg/8 h. The effects of analgesic agents were evaluated on the basis of patient's appreciation of the degree of pain and relief and on the basis of an observer who did not know the therapeutic regime administered. Results were compared according to the analysis of variance in a graded factorial design. A p value less than 0.05 was considered significant. RESULTS: The degree of pain was significantly lower in groups C, D, G and H (specially in G and H) than in the remaining groups, but there were no significant differences between them. The lowest pain relief was observed in groups A, B, E and F. The highest attenuation of pain was achieved in groups G and H. The highest attenuation of pain was achieved in groups G and H. The observer considered that the two latter groups were those with the highest pain relief, followed by groups C and D. The remaining patients failed to show appreciable improvement. Nausea and vomiting only occurred in some patients after administration of a bolus of meperidine. There were no other secondary effects. CONCLUSIONS: The best degree of postoperative analgesia is achieved after administration of continuous infusion of meperidine 100 mg/8 h. Simultaneous infusion of ASL 1.800 mg/8 h did not improve the analgesia obtained with a bolus of 900 mg of ASL nor with a bolus of 50 mg of meperidine. Secondary effects were only nausea and vomiting and coincided with the administration of a bolus of meperidine.

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