Liang Yanchun

GW28-e1153 Study of Intrinsic QRS Complex Duration Changes 6 Months After Cardiac Resynchronization Therapy

Cardiac resynchronization therapy (CRT) is one of the important advances in the treatment of ventricular systolic heart failure (HF) in recent years. It can reduce the mortality and improve the quality of life of patients. Patients who had response to CRT were often accompanied with a reversal of

ASSA14-02-09 The strategy of radiofrequency catheter ablation in special left accessory pathway

Objective To explore the strategy of radiofrequency catheter ablation in special left accessory pathway. Methods From January 2013 to December 2013, total 288 patients with left accessory pathway were ablated in our hospital. Among them, special left accessory pathways were found in 13 patients. Gap phenomenon was found in 6 patients, slow accessory pathway in 2 patients, combination with persistent left superior vena cava in 3 patients, peripheral vascular serious circuity in 1 patient, combination with atrial fibrillation and atrial flutter in 1 patient. All the patients were ablated through aortic retrograde approach, transseptal approach and via coronary sinus approach. Results Thirteen patients were all ablated successful. Eight patients were ablated through aortic retrograde approach, and four patients with left side accessory pathway were accomplished through transseptal approach, and one patient were ablated via coronary sinus. The success rate was 100%, and complication was not occurred. Gap phenomenon was found in 6 patients with no adverse transmission above 400 ms stimulation and with adverse transmission under 350 ms stimulation. Heart rate and blood pressure were decreased in one patient with persistent left superior cave during ablation. ST-T changing in ECG was confirmed no coronary artery disease, and considered left boundle branch block. Two patients with slow accessory pathway were ablated in left free wall where VA was not fused. One patient with poliovirus and peripheral vascular serious circuity was ablated through transseptal approach after failure via aortic retrograde approach. One patient with atrial fibrillation and atrial flutter was ablated in coronary vein successful. Conclusions During ablation in left accessory pathway, we may get into trouble in some cases. After identifying carefully and ablation through different methods, high success rate was still obtained.

ASSA14-02-08 Cryoballoon ablation for paroxysmal atrial fibrillation

Objective To explore the methods, strategy and short-term outcome of cyroballoon ablation for paroxysmal atrial fibrillation. Methods To analyse the data of cryoballoon ablation for the first 5 patients with PAF in our hospital. Results The mean procedure time of the 5 patients were 153 ± 43.5 min (170 min, 100 min, 120 min, 210 min and 165 min). The mean fluoroscopy time was 51.2 ± 15.0 min (54 min, 33 min, 41 min, 72 min and 56 min). The mean time of cryoballoon ablation in each pulmonary vein was 209.0s ± 74.7s (29s – 300s). The temperature of the cryoballoon was -43.5 ± 8.6°C (-27°C – -61°C). The cryoballoon ablation times in each vein was 3 ± 1.3 (2–6 times per pulmonary vein). The complications of the procedure (such as phrenic nerve palsy, pericardia tamponade) was not happened. In one patient, the left pulmonary vein potential was not completely isolated. The radiofrequency ablation catheter was used to achieve pulmonary vein isolation entirely. After 1 or 2 months follow-up, atrial fibrillation was not happened in all 5 patients. Conclusions Cryoballoon ablation of atrial fibrillation is relatively simple, no 3D mapping, and shorter learning curve. But the X-ray fluoroscopy time is longer in earlier period and need making progress.

ASSA13-02-15 Clinical Characteristics of 4 Cases of Polymorphic Ventricular Tachycardia/Ventricular Fibrillation Initiated by Idiopathic Premature Ventricualr Contraction Originating from Right Ventricular Outflow Tract

Background Ventricular fibrillation and/or polymorphic ventricular tachycardia are occasionally initiated by ventricular extrasystoles originating from the right ventricular outflow tract (RVOT) in patients without structural heart disease. Objective The aim of this study was to report clinical characteristics of 4 cases of polymorphic ventricular tachycardia/ventricular fibrillation (PVT/VF) initiated by idiopathic premature ventricualr contraction (PVC) originating from RVOT. Methods Among 76 patients with ventricular tachycadia (VT) arising from RVOT, the clinical characteristics of 4 patients with PVT/VF triggered by PVC originating from RVOT were investigated and compared with the clinical characteristics of the other 72 patients. Results The same PVC morphology was shown in triggering PVCs that initiated PVT/VF and in isolated PVCs. The coupling intervals of the above two kinds of PVCs were markdly different. The coupling intervals of triggering PVCs were shortened in 2 cases and prolonged in the remain 2 cases compared with those of isolated PVCs, and the variation magnitude of the coupling interval in every case was more than 70 ms. The coupling intervals of isolated PVCs were not fixed in 1 case. The number of PVCs per day, the coupling interval of isolated PVC and the baseline QT interval were 15427 ± 1109, 419 ± 22ms and 404 ± 15ms respectively in 72 monomorphic VT patients. The numbers of PVCs per day of 3 of the 4 PVT/VF patients were equivalent to those of 72 VT patients, and the same equivalence was found in the coupling intervals of isolated PVC and the baseline QT intervals of the 4 patients. The cycle lengths of PVT/VF were all less than 280 ms, which was shorter than that of monomorphic VT (324 ± 59ms) obviously. Among 4 patients, episodes of syncope were documented in 2 patients, and the syncope rate of 72 VT patients was 4.1%. Activating mapping and pacing mapping confirmed that the PVCs of all these 4 patients originated from septal of RVOT, and PVCs were successfully eliminated by radiofrequency catheter ablation. Conclusions PVCs that triggered PVT/VF and originated from tract RVOT had the characteristics of unstable coupling intervals and short circle lenth of PVT/VF. Radiofrequency catheter ablation was effective as a treatment option for these patients.

ASSA13-02-4 Electrophysiological Characteristic and Ablation of Epicardial Idiopathic Ventricular Arrhythmias Arising Around Left Fibrous Triangle

Background The success rate of radiofrequency catheter ablation of ventricular arrhythmias originating from left fibrous triangle (LFT) is not high. This article was to discuss the characteristics of sueface electrocardiogram and the strategy of ablation of ventricular arrhythmias originating from LFT. Methods From February 2002 to March 2012, total 323 patients with outflow ventricular arrhythmias were ablated in our hospital, incluing 46 patients whose ventricular arrhythmias originated from the LFT. The mean age of the 46 patients was 44 ± 13 years (16–87 years), and 24 of them (52.2%) were male. Thirty patients had frequent premature ventricular contractions (PVCs) and 16 patients had both PVCs and nonsustained or sustained ventricular tachycardia (VT). All the patients were examined with ECG, electrophysiology, active mapping and pace mapping. The computer tomography angiogram (CTA) 3D reconstruction of coronary artery, venouswas completed in 20 patients. Results Successful ablation was achieved in 41 of the 46 patients (89.1%, 41/46) targeting left coronary cusp (LCC, 30 patients), infra aortic valve (infra AV, 6 patients) and great cardiac vein (GCV, 5 patients). The surface ECG in all the three groups presented with inferior axis and R/S-transition in lead V1 and V2. There were no differentces in the total QRS duration in the three groups. Most of the patients presented with right bundle branch block (RBBB) morphology in infra AV group and GCV group compared with LCC group (67%, 80% vs 15%, P = 0.002). Regarding to the classification of the LFT according to CTA, the patterns of distribution were as follows: “closed” in 10 (50%, 10/20) hearts; “completely opened” in 2 (10%, 2/20); “inferiorly opened” in 5 (25%, 5/20) hearts and “superiorly opened” in 1 (5%, 1/20) hearts. In the remaining 2 (10%, 2/20), there were not any distances between cardiac vein and artery. The closest distance between the corner of the GCV and LCC is 17.6 ± 4.2 mm (9.1mm ∼ 26.3mm). Conclusions Ventricular arrhythmias originating from the LFT can be ablated in the nadir of the LCC, infra AV and the GCV. The success rate may be impacted by the distance from the GCV and the LCC.

ASSA13-02-22 Application of a Novel Pacing Guide Wire in Cardiac Resynchronization Therapy

Background The implantation of left ventricular (LV) lead was the most complicated process in the cardiac resynchronization therapy (CRT), the aim of this study was to investigate the availability of a novel Visionwire guide wire in the implantation ofLVlead in CRT. Methods Five heart failure patients selected for CRT were involved in the study. The pacing threshold, R-wave sensing, phrenic nerve stimulation at local coronary sinus (CS) branch were measured by the Visionwire guide wire and LV lead separately. Results The pacing parameters were analysed through the Visionwire guide wire and LV lead separately at the 16 CS branches in 5 patients. There was no significant difference between the pacing parameters measured by the two methods. Significant correlation was found betweenLVpacing threshold assessed by the Visionwire guide wire andLVlead (r = 0.90, P < 0.01). Correlation for R wave sensing was also significant (r = 0.67, P < 0.01). The pacing sites accompanied with phrenic nerve stimulation while pacing at 10 V/0.42 ms were similar by the two methods. Visionwire guide wire could be used for local potential electrical mapping. The procedure time for pacing test in a single coronary sinus branch by Visionwire guide wire was much less than that by LV lead (12.4 ± 7.5min vs 18.3 ± 12.2min, P < 0.01). Conclusions Visionwire guide wire facilitated transvenousLVlead implantation by prediction of pacing parameter and locate the target CS branch quickly. The electrophysiological mapping function of Visionwire guide wire as a unipolar lead might have further potential usefulness.

ASSA13-02-27 Long-Term Performance of Active Fixation Pacing Leads in Right Atrium

Background More and more active-fixation leads were used in the right atrium during the implantation of pacemaker, the aim of this study was to explore the feasibility of active-fixation right atrial leads in the application of pacemaker and observe the changes of long-term pacing parameters. Methods Sixty patients (32 males and 28 females, mean aged 65.25 ± 13.95 years) were involved in this study, 4 cases implanted with single-chamber pacemaker (AAIR) and 56 cases implanted with dual-chamber pacemaker (DDDR), who underwent the active-fixation leads implantation in the right atrium for permanent pacing. The follow-up period was 12 months after implantation. Results The active-fixation atrial leads were successful implanted in all patients and there were no complication during the operation, 52 leads implanted in the right atrial appendage, 3 in the right atrial septum and 5 in the right atrial lateral wall. The pacing thresholds at the implanted moment were obviously higher and declined rapidly. No thresholds change occurred at the end of the operation, in 48 hours, 3 months, 6 months, 12 months after operation. The impedances were quickly decreased at the end of the operation and 48 hours after the operation, no obvious sense parameters changed. 1 patient (1.7%) with acute atrial electrode dislodgment at 2 hours after operation, we resetted the active -fixation lead successfully. No complications such as lead perforation and cardiac tamponade occurred. Conclusions It was safe and feasible in the implantation of active- fixation leads in right atrium. The pacing parameters of active-fixation leads in right atrium were stable during the periods of 12 months after operation.

ASSA13-02-14 The Comparison Between the Active-Fixation Leads and Passive-Fixation Leads in Right Ventricular Apical Pacing

Background More and more active-fixation leads were used in the implantation of pacemaker, but compared with the traditional passive-fixation leads, the differences of the pacing parameter were not clearly known. Objective The aim of this study was to compare the pacing parameters of active-fixation leads and passive-fixation leads in right ventricular apical pacing. Methods There were 54 patients implanted with single or dual chamber pacemaker involved in this study from January 2010 to May 2010 followed up for 3 months after operation. In these patients 21 with passive-fixation lead (Group I) and 33 with active-fixation lead (Group II). All the leads were implanted in right ventricle apex, the average age was 66.23 ± 13.90 years old, 21 patients with single chamber pacemaker and 33 with dual chamber pacemaker. Results There were no obvious changes in the pacing parameters between the two groups not only during the operation (thresholds: 0.56 ± 0.20 vs 0.57 ± 0.21; pacing impedances : 818.25 ± 267.71 vs 823.59 ± 284.46; R Wave: 10.64 ± 3.08 vs 10.47 ± 3.10) but also at 1 month (thresholds: 0.55 ± 0.18 vs 0.55 ± 0.18; pacing impedances: 542.72 ± 190.30 vs 531.91 ± 189.48; R Wave: 10.53 ± 3.60 vs 10.22 ± 3.63) and 3 months after the operation (thresholds : 0.57 ± 0.17 vs 0.56 ± 0.17; pacing impedances: 499.80 ± 135.37 vs 494.29 ± 135.74; R Wave: 10.72 ± 3.48 vs 10.47 ± 3.53)(P > 0.05). But there were 1 of 33 patients in Group II (1/33.3%) with higher pacing threshold after operation. The threshold reached to 6.0 V at the second day after operation and the patient was dealt with dexamethasone for 1week, and there was no change of the higher pacing threshold, so we had to implant the new passive-fixation lead in the right ventricular apex and extract the old active-fixation lead simultaneously. The pacing thresholds were stable followed for 3 months. No patients with severely higher pacing thresholds in Group I. Conclusions There were no obvious differences in the pacing parameters between the passive-fixation leads and active-fixation leads in right ventricular apical pacing. But it was possible that the stimulation thresholds were individually higher in patients with active-fixation leads than those with passive-fixation leads (3.3% vs 0). The long-term parameter changes still were observed.

ASSA13-02-2 Inducibility of Atrial Arrhythmia After Circumferential Pulmonary Vein Isolation in Patients with Paroxysmal Atrial Fibrillation: Clinical Predictor and Outcome During Follow-Up

Background Inducibility of atrial arrhythmia after circumferential pulmonary vein isolation (CPVI) in patients with paroxysmal atrial fibrillation (AF) were analysed to assess whether inducibility of atrial arrhythmia could be used as a clinical predictor of AF recurrence and whether non-inducibility of AF was a clinically useful end point. Methods Forty one consecutive patients with symptomatic paroxysmal AF underwent CPVI guided by 3D mapping system and single Lasso technique. After achievement of CPVI, the induction of atrial arrhythmia (AA) was performed. AA was induced by rapid atrial pacing within the proximal coronary sinus and right atrium. AA was considered inducible only if its duration was more than 30 seconds. Symptoms, Surface ECG, and 24h Holter recording were followed up after the procedure. Results Sustained atrial arrhythmias were induced after CPVI in 16 of 41 patients (39.0%). Thirteen of the 35 patients (37.1%) had inducible AA after the initial procedure and 3 of the 6 patients (50%) after the second procedure, and there was no difference between the two groups (P > 0.05). There were no differences in the baseline data between the two groups (P > 0.05). During an average 6 months of follow-up, 7 of the 16 patients (43.8%) in the AF inducible group had AF recurrence, and 8 of the 25 patients (32.0%) in the AF non-inducible group had AF recurrence (P > 0.05). After the second procedure, 1 of the 3 patients in the AF inducible group had AF recurrence, and no patient of the 3 patients in the AF non-inducible group had AF recurrence (P > 0.05). Four of the 9 patients (44.4%) whose inducible AA lasted between 1 min and 5 min had AF recurrence; 1 of the 3 patients (33.3%) whose AA duration more than 5 min and less than 10 min had AF recurrence; 2 of the 4 patients (50%) whose AA duration more than 10 min had AF recurrence. The recurrences among the above groups showed no significant difference (P > 0.05). The sensitivity, specificity, positive, and negative predictive values of the AF induction test to predict the 6-month ablation outcome were 41.7%, 65.2%, 27.2% and 68.2%, respectively. Conclusions Inducibility of atrial arrhythmia could not predict the clinical efficacy of CPVI in patients with paroxysmal AF, and non-inducibility could not be qualified as a reliable procedural endpoint.

ASSA13-02-8 Safety, Efficacy and Learning Curve of Catheter Ablation of Paroxysmal Atrial Fibrillation Using Circumferential Pulmonary Vein Isolation Technique in the Single Centre and in a Single Operator

Background CARTO anatomical mapping system and circumferential pulmonary vein isolation (CPVI) technique has been used to cure paroxysmal atrial fibrillation (PAF) in most hospitals in China, and have achieved a high success rate. But whether the successful rate, the recurrence rate and the safety are related to learning cure is still unclear. Methods From December 2004 to December 2010, 258 consecutive patients who underwent CPVI for PAF in our hospital were collected. The patients were divided into three groups with equal patient numbers according to the time sequences. Group I consisted of the first 86 cases, Group II consisted of the second 86 patients, and Group III consisted of the last 86 cases. Age, gender, course of disease, echocardiography, other atrial arrhythmias, basic diseases were analysed statistically. The operation X-ray exposure time, recent recurrence, late recurrence and re-ablation procedures were also analysed. In addition, the learning curve of CPVI for PAF and its relationship with peri-operative period complications, and the risk factors to predict the recurrence of atrial arrhythmias were analysed, too. Results There were no significant differences in patients’ age, gender, basic diseases and LAD among three groups. The rates of early recurrence in Group I, Group II and Group III were 38/86 (44.2%), 26/86 (30.2%) and 21/86 (24.4%) respectively (P < 0.05). The successful rates at 1 year were 44.2%, 51.2%, 64.0% respectively (P < 0.05) in three groups. The incidence of general complications was 12.8% in Group I, 4.7% in Group II, and 2.3% in group III. There were statistically significant differences between the total complication rates among the three groups. In many variables, left atrium dimension (LAD) enlargement and early recurrence were the risk factors of recurrent AF (P < 0.01 and P < 0.05, respectively). Conclusion For an experienced operator, CPVI has a higher success rate, a lower recurrence and a lower complication rate for radiofrequency catheter ablation of PAF. However, for a beginning operator, the success rate was relatively lower, both the recurrence and the complication rate were higher, and the X-ray exposure time was longer. The strengthened training of CPVI technique for PAF may be very important for the new operator to increase the success and to avoid or decrease the incidence of complications.