OBJECTIVES: This study sought to describe a new adverse effect of percutaneous radiofrequency(RF) ablation for atrial fibrillation(AF). BACKGROUND: Extension of the RF lesion beyond atrial myocardium may affect medias...OBJECTIVES: This study sought to describe a new adverse effect of percutaneous radiofrequency(RF) ablation for atrial fibrillation(AF). BACKGROUND: Extension of the RF lesion beyond atrial myocardium may affect mediastinal structures other than the esophagus. METHODS: Circular mapping-guided isolation of the pulmonary veins was performed in two different electrophysiology laboratories, either individually and supplemented by ostial and posterior left atrial(LA) ablation or two by two with a series of ostial and posterior LA lesions. The RF energy was delivered point by point through a 5-mm open-tip irrigated catheter(40W maximum) or an 8-mm-tip catheter(45W maximum). RESULTS: In four(two in each electrophysiology laboratory) of 367 patients undergoing catheter ablation for AF, abdominal pain and distension developed within 48 h after the procedure. Investigation showed acute pyloric spasm and gastric hypomotility, probably the result of LA endocardially delivered RF affecting the periesophageal vagi. Complete spontaneous recovery occurred in two patients, but laparoscopic esophagojejunal anastomosis and endoscopic intra-pyloric Botulinum toxin injection, respectively, were performed to remedy delayed gastric emptying in two patients. CONCLUSIONS: Thermal injury during endocardial LA RF energy delivery may extend into the mediastinum and rarely may involve the periesophageal nerves, resulting in a syndrome of acute delayed gastric emptying. Marked anatomic variability of periesophageal vagi renders it difficult to reliably avoid the area overlying this plexus, therefore, we advocate a reduction in maximum RF power and application duration on all of the posterior LA to try to avoid this complication.展开更多
Introduction: Studies evaluating changes in HRV preceding the onset of ventric ular arrhythmias using conventional techniques have shown inconsistent results. Time-frequ-ency analysis of HRV is traditionally performed...Introduction: Studies evaluating changes in HRV preceding the onset of ventric ular arrhythmias using conventional techniques have shown inconsistent results. Time-frequ-ency analysis of HRV is traditionally performed using short-term F ourier transform(STFT). Wavelet transform(WT) may however be better suited for a nalyzing non-stationary signals such as heart rate recordings. Methods and resu lts: We studied patients with a history of myocardial infarction implanted with a defibrillator with an extended memory. The RR intervals during the 51 min prec eding ventricular events requiring electrical therapy were retrieved, and HRV st udied by WT and STFT. 111 episodes of ventricular arrhythmia were retrieved from 41 patients(38 males, age 64±8 years). Heart rate increased significantly befo re arrhythmia. There was no significant variation in low frequency/high frequenc y components(LF/HF) observed for the group as a whole, probably due to a great d egree of heterogeneity amongst individuals. A subset of 30 patients also had hea rt rate recordings performed during normal ICD follow-up. WT did not show any d ifference in HRV before arrhythmia onset and during control conditions. Conclusi on: Variations in HRV before onset of ventricular arrhythmias were not apparent in this large dataset, despite use of optimal tools for studying time-frequency analysis.展开更多
文摘OBJECTIVES: This study sought to describe a new adverse effect of percutaneous radiofrequency(RF) ablation for atrial fibrillation(AF). BACKGROUND: Extension of the RF lesion beyond atrial myocardium may affect mediastinal structures other than the esophagus. METHODS: Circular mapping-guided isolation of the pulmonary veins was performed in two different electrophysiology laboratories, either individually and supplemented by ostial and posterior left atrial(LA) ablation or two by two with a series of ostial and posterior LA lesions. The RF energy was delivered point by point through a 5-mm open-tip irrigated catheter(40W maximum) or an 8-mm-tip catheter(45W maximum). RESULTS: In four(two in each electrophysiology laboratory) of 367 patients undergoing catheter ablation for AF, abdominal pain and distension developed within 48 h after the procedure. Investigation showed acute pyloric spasm and gastric hypomotility, probably the result of LA endocardially delivered RF affecting the periesophageal vagi. Complete spontaneous recovery occurred in two patients, but laparoscopic esophagojejunal anastomosis and endoscopic intra-pyloric Botulinum toxin injection, respectively, were performed to remedy delayed gastric emptying in two patients. CONCLUSIONS: Thermal injury during endocardial LA RF energy delivery may extend into the mediastinum and rarely may involve the periesophageal nerves, resulting in a syndrome of acute delayed gastric emptying. Marked anatomic variability of periesophageal vagi renders it difficult to reliably avoid the area overlying this plexus, therefore, we advocate a reduction in maximum RF power and application duration on all of the posterior LA to try to avoid this complication.
文摘Introduction: Studies evaluating changes in HRV preceding the onset of ventric ular arrhythmias using conventional techniques have shown inconsistent results. Time-frequ-ency analysis of HRV is traditionally performed using short-term F ourier transform(STFT). Wavelet transform(WT) may however be better suited for a nalyzing non-stationary signals such as heart rate recordings. Methods and resu lts: We studied patients with a history of myocardial infarction implanted with a defibrillator with an extended memory. The RR intervals during the 51 min prec eding ventricular events requiring electrical therapy were retrieved, and HRV st udied by WT and STFT. 111 episodes of ventricular arrhythmia were retrieved from 41 patients(38 males, age 64±8 years). Heart rate increased significantly befo re arrhythmia. There was no significant variation in low frequency/high frequenc y components(LF/HF) observed for the group as a whole, probably due to a great d egree of heterogeneity amongst individuals. A subset of 30 patients also had hea rt rate recordings performed during normal ICD follow-up. WT did not show any d ifference in HRV before arrhythmia onset and during control conditions. Conclusi on: Variations in HRV before onset of ventricular arrhythmias were not apparent in this large dataset, despite use of optimal tools for studying time-frequency analysis.
