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Junctional Rhythm (junctional + rhythm)
Selected AbstractsPatterns of Accelerated Junctional Rhythm During Slow Pathway Catheter Ablation for Atrioventricular Nodal Reentrant Tachycardia: Temperature Dependence, Prognostic Value, and Insights into the Nature of the Slow PathwayJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2000ALAN B. WAGSHAL M.D. Slow Pathway Accelerated Junctional Rhythm. Introduction: Although accelerated junctional rhythm (AJR) is a knuwn marker for successful slow pathway (SP) ablation sites. AJR may just be a regional effect of the anisotropic conduction properties of this area of the heart. We believe that detailed assessment of the AJR might provide insight into the SP specificity of this AJR and perhaps the nature of the SP itself. Methods and Results: Our ablation protocol consisted of 30-second, 70°C temperature-controlled ablation pulses with assessment after each pulse. Serial booster ablations were performed at the original successful site and at least 2 to 3 nearby sites to assess for residual AJR after the procedure in 50 consecutive SP ablations. We defined three distinct patterns of AJR: continuous AJR that persisted until the end of energy delivery (group 1, 25 patients); alternating or "stuttering" AJR that persisted throughout energy delivery (group II, 9 patients); and AJR that ended abruptly during energy delivery (group III, 16 patients). Mean ablation temperatures in the three groups was 57°± 5°C, 54°± 5°C, and 63°± 5°C, respectively (P = 0.0002 for groups I and II vs group III). Ten of 34 (29%) patients in groups I and II ("low-temperature ablation") exhibited residual SP (jump and/or single echo heats) despite tachycardia noninducibility, and 25 of 34 (73%) patients had residual AJR during the booster ablations, but neither of these was seen in any group III patients. Conclusion: Ablation temperature correlates with the pattern of AJR produced during SP ablation. That higher temperature lesions simultaneously abolish all SP activity as well as the focus of AJR suggests that this AJR is specific for the SP and is not a nonspecific regional effect. [source] Dynamic Effects of Exercise and Different Escape Rhythms on the Supernormal Period of an Accessory PathwayJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 6 2007JEREMY J. LUM M.D. Spontaneous conduction during the supernormal period (SNP) of accessory pathways (AP) is rare and observed only during atrio-ventricular block (AVB). The effect of exercise and different escape rhythms on the SNP is unknown. We evaluated these factors on the SNP of a para-Hisian AP after a failed ablation complicated by AVB. The SNP onset and duration were later and longer during paced versus junctional rhythm. Exercise caused linear shortening of the SNP that was directly related to junctional cycle length. The SNP is a dynamic window shifting in parallel with AP refractoriness and affected by exercise and type of escape rhythm. [source] Patterns of Accelerated Junctional Rhythm During Slow Pathway Catheter Ablation for Atrioventricular Nodal Reentrant Tachycardia: Temperature Dependence, Prognostic Value, and Insights into the Nature of the Slow PathwayJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2000ALAN B. WAGSHAL M.D. Slow Pathway Accelerated Junctional Rhythm. Introduction: Although accelerated junctional rhythm (AJR) is a knuwn marker for successful slow pathway (SP) ablation sites. AJR may just be a regional effect of the anisotropic conduction properties of this area of the heart. We believe that detailed assessment of the AJR might provide insight into the SP specificity of this AJR and perhaps the nature of the SP itself. Methods and Results: Our ablation protocol consisted of 30-second, 70°C temperature-controlled ablation pulses with assessment after each pulse. Serial booster ablations were performed at the original successful site and at least 2 to 3 nearby sites to assess for residual AJR after the procedure in 50 consecutive SP ablations. We defined three distinct patterns of AJR: continuous AJR that persisted until the end of energy delivery (group 1, 25 patients); alternating or "stuttering" AJR that persisted throughout energy delivery (group II, 9 patients); and AJR that ended abruptly during energy delivery (group III, 16 patients). Mean ablation temperatures in the three groups was 57°± 5°C, 54°± 5°C, and 63°± 5°C, respectively (P = 0.0002 for groups I and II vs group III). Ten of 34 (29%) patients in groups I and II ("low-temperature ablation") exhibited residual SP (jump and/or single echo heats) despite tachycardia noninducibility, and 25 of 34 (73%) patients had residual AJR during the booster ablations, but neither of these was seen in any group III patients. Conclusion: Ablation temperature correlates with the pattern of AJR produced during SP ablation. That higher temperature lesions simultaneously abolish all SP activity as well as the focus of AJR suggests that this AJR is specific for the SP and is not a nonspecific regional effect. [source] Severe hypotension during the development of low-nodal junctional rhythmACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2009Y. Asakura No abstract is available for this article. [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] Ectopic Atrial Rhythm with Exit Block Following Catheter Ablation for Focal Atrial Tachycardias in a Patient with Prior Surgery for Atrial Septal DefectPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 6 2002KIMIE OHKUBO OHKUBO, K., et al.: Ectopic Atrial Rhythm with Exit Block Following Catheter Ablation for Focal Atrial Tachycardias in a Patient with Prior Surgery for Atrial Septal Defect. The patient was a 40-year-old woman with a history of surgery for atrial septal defect and catheter ablation for typical atrial flutter. An electrophysiological study was performed because she had palpitation and syncope. She had ectopic atrial rhythm originating from low lateral RA. Two focal atrial tachycardias ([1] superior vena cava-RA junction and [2] a low posteroseptal RA) were successfully ablated. Following catheter ablation for the second atrial tachycardia, she developed junctional rhythm because ectopic atrial rhythm showed exit block. However, atrial activation of junctional rhythm could conduct into the ectopic atrial rhythm focus and reset the rhythm when atrial activation of junctional rhythm reached the blocked line after atrial refractoriness by preceding ectopic atrial rhythm. [source] | ||||||||||