廖自立
中国医学科学院阜外医院 心血管内科
BACKGROUND:Ablation of para-Hisian accessory pathway (AP) poses high risks of atrioventricular block. We developed a pacing technique to differentiate the near-field (NF) from far-field His activations to avoid the complication.METHODS AND RESULTS:Three-dimensional mapping of the right ventricle was performed in 15 mongrel dogs and 23 patients with para-Hisian AP. Using different pacing outputs, the NF- and far-field His activation was identified on the ventricular aspect. Radiofrequency application was delivered at the NF His site in 8 (group 1) and the far-field His site in 7 dogs (group 2), followed by pathologic examination after 14 days. NF His activation was captured with 5 mA/1 ms in 10 and 10 mA/1 ms in 5 dogs. In group 1, radiofrequency delivery resulted in complete atrioventricular block in 3, right bundle branch block with HV (His-to-ventricular) interval prolongation in 1, and only right bundle branch block in 2 dogs, whereas no changes occurred in group 2. Pathologic examination in group-1 dogs showed complete or partial necrosis of the His bundle in 4 and complete necrosis of the right bundle branch in 5 dogs. In group 2, partial necrosis in the right bundle branch was found only in 1 dog. Using this pacing technique, the APs were 5.7±1.2 mm away from the His bundle located superiorly in 20 or inferiorly in 3 patients. All APs were successfully eliminated with 1 to 3 radiofrequency applications. No complications and recurrence occurred during a follow-up of 11.8±1.4 months.CONCLUSIONS:Differentiating the NF His from far-field His activations led to a high ablation success without atrioventricular block in para-Hisian AP patients.
Circulation. Arrhythmia and electrophysiology 2017
AIMS:The characteristics and response to ablation therapy of focal atrial tachycardia (AT) originating from the distal portion of left atrial appendage (LAAd) are still not quite clear up to now. The goal of this study is to characterize electrocardiographic and electrophysiological features and radiofrequency ablation (RFA) outcomes in patients with focal AT originating from the LAAd.METHODS AND RESULTS:Fourteen patients (2.1%) (mean age, 25 ± 10 years; nine women; mean symptom duration, 5 ± 5 years) undergoing RFA of focal AT originating from the LAAd were included out of 668 RFA patients. Activation mapping was performed. P waves were classified as negative, positive, isoelectric, or biphasic. Tachycardia that was incessant in all, demonstrated a characteristic P-wave morphology and endocardial activation pattern: P wave was negative in leads I and aVL, highly positive in the inferior leads, and broad and positive in lead V₁. Radiofrequency ablation was acutely successful in 13 of 14 patients. The endocardial activation time of the successful RFA sites was 47.1 ± 4.3 ms before the onset of P wave. There were no complications in any of the 14 patients and long-term success was achieved in 13 of 13 successful RFA patients during follow-up (5 ± 2 years).CONCLUSION:The LAAd is an uncommon site of origin for focal AT (2.1% incidence). In this case series, focal ATs originating from the LAAd had typical electrophysiological and electrocardiographic characteristics. Focal ablation yielded high acute success rate with low rate of recurrence during follow-up.
Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology 2012
BACKGROUND:We sought to investigate the feasibility of radiofrequency catheter ablation of atrioventricular node reentrant tachycardia and the ideal site for slow pathway (SP) ablation in congenitally corrected transposition of the great arteries.METHODS AND RESULTS:Nine patients with congenitally corrected transposition of the great arteries referred for catheter ablation of atrioventricular node reentrant tachycardia were studied. A single His potential was recorded in 8 patients (89%, 6 {S,L,L} and 2 {I,D,D}). The earliest atrial activation during retrograde atrioventricular node conduction occurred at His bundle region (HBE; n=7) or shifting from HBE to coronary sinus ostium (n=1, {S,L,L}). Two anatomically separate His potentials were recorded in 1 patient (11%, {S,L,L}), one at the anteroseptum (HBE-1) and the other at the confluence of the pulmonary and mitral annulus (HBE-2). In 8 cases with a single His potential recorded, SP was abated at the posterior-midseptum, 2 ({S,L,L}) at the right posteroseptum, 1 ({S,L,L}) at the left posteroseptum, and 5 (3 {S,L,L} and 2 {I,D,D}) at the midseptum after failure of energy application at the posteroseptum. Junctional rhythm was observed during radiofrequency catheter ablation in all 8 of the cases. In the remaining patient with 2 anatomically separate His potentials recorded, SP was successfully ablated from the confluence of the pulmonary and mitral annulus, slightly below the HBE-2. Junctional rhythm was also induced during radiofrequency catheter ablation.CONCLUSIONS:In {S,L,L} or {I,D,D}, radiofrequency catheter ablation of atrioventricular node reentrant tachycardia is feasible. SP input region can mainly be found in the posterior midseptum, especially in patients with single penetrating atrioventricular nodes. SP could usually be successfully ablated in these regions.
Circulation. Arrhythmia and electrophysiology 2012
BACKGROUND:Atriofascicular and decremental atrioventricular pathways are variants of accessory pathways with anterograde decremental conduction properties. They result in typical wide Quantronic Resonance System (QRS) tachycardia of left bundle branch block morphology. Data on the sinus rhythm electrocardiographic characteristics are limited.METHODS AND RESULTS:Thirty patients with accessory pathways of anterograde decremental conduction properties were studied retrospectively (10 atriofascicular pathways and 20 decremental atrioventricular pathways). All patients had a pre-excited atrioventricular tachycardia with anterograde conduction over anterograde decrementally conducting fiber. Eighteen patients fulfilled criteria of minimal pre-excitation during sinus rhythm before ablation. In 10 patients (33%), delta wave was absent, and the only abnormality was terminal QRS slurring or notching on the ECG. It was mainly in leads I, V5, and V6. After ablation, terminal QRS slurring or notching disappeared in all 10 patients. We also did a survey in a control group comprised of 200 subjects without structural heart disease who were matched for age and sex. Terminal QRS slurring or notching was found in 3%.CONCLUSIONS:This study showed a high prevalence of terminal QRS slurring or notching in patients with atriofascicular or decremental atrioventricular pathways. It can be the sole manifestation of such accessory pathways during sinus rhythm, and disappearance of terminal slurring or notching can be the only hallmark of successful ablation visible on the surface ECG.
Circulation. Arrhythmia and electrophysiology 2011
