A 33-year old man with a history of transient palpitations presented to casualty with sustained tachycardia. His ECG showed pre-excited atrial fibrillation, with a left-sided accessory pathway. He was cardioverted to sinus rhythm, and transferred for electrophysiological treatment. A quadrupolar lead was advanced from the right femoral vein under fluoroscopy, and …

Abstract Background Ablation of the atrioventricular (AV) node, following the insertion of a permanent pacemaker, is a treatment option for symptomatic atrial fibrillation (AF) where rate control is poor, despite maximally tolerated pharmacological intervention or percutaneous AF ablation [1], and yet there is limited data on long-term outcomes. Purpose The purpose of this study is to investigate post AV node ablation follow up outcomes, including the incidence and timeframe of conversion of paroxysmal to persistent AF; incidence and timeframe of upgrade to biventricular pacemakers; and mortality. Methods This observational descriptive study looked at the post-procedure follow-up outcomes of patients who underwent AV node ablation at our centre between March 2015 and June 2019. Retrospective analysis of prospectively collected data was analysed. The demographics of the patients, including their age, gender, co-morbidities, pre-ablation left ventricular ejection fraction (LVEF) and medications were recorded. The follow up outcomes investigated included the change in LVEF, the proportion of patients whose AF converted from paroxysmal to persistent, the proportion of patients requiring upgrade to biventricular devices, and deaths within 6 months of ablation. Outcomes were compared between those who had a biventricular pacemaker pre-ablation and those who had single/dual chamber pacemakers. Results 296 patients with a mean age of 72.7± 8.5 years and a female to male ratio of 54.1% : 45.9% were included. 94 patients (31.8%) had paroxysmal AF pre- ablation. 51.6% of those who had paroxysmal AF pre-ablation converted to persistent AF over a median period of 3 years (interquartile range, 3 years). Among those who had a biventricular pacemaker pre-ablation, 56.5% of those with paroxysmal AF converted to persistent, compared to 47.4% of those with a dual pacemaker pre-ablation p=ns Among patients with dual chamber pacemakers, those who remained in paroxysmal AF post-ablation had a mean CHADVASC score of 3.2 (range of 1-6) compared to 3.7 (range of 2-6) in those whose AF converted to persistent (p=0.19). 9 patients (3%) died within less than 6 months of the procedure, with 1 patient dying within 6 days. 13% of the patients originally having a single or dual chamber pacemaker required an upgrade to a biventricular pacemaker over a median period of 1.25 years (interquartile range 1.1 years). All the patients who required an upgrade to a biventricular pacemaker had normal LVEF pre-ablation except for one patient who had mild LV impairment. Conclusions A significant proportion of patients with paroxysmal AF converted to persistent AF following AV node ablation and having a biventricular pacemaker did not offer benefit in keeping people in paroxysmal AF.A considerable number of people required an upgrade to biventricular pacemaker over a short time frame even though they had normal LVEF pre AV nodal ablation.

Introduction Radiofrequency (RF) is a widely used technology for Atrial Fibrillation (AF) ablation. However, settings for optimal lesion geometry to obtain transmural, durable, and safe lesions are still debated. High Power Short Duration (HPSD) is a novel strategy aiming to create more efficient lesions. We examine the safety and efficacy of the QDOT Micro catheter using its dual abilities, including QMODE+ defined by a very HPSD (90W/4secs) and conventional power temperature controlled QMODE. Methods All patients undergoing Pulmonary Vein Isolation (PVI) using vHPSD for AF at a single UK centre were included in a prospective registry. Patients with additional ablation lines, other than Cavotricuspid Isthmus (CTI), were excluded. Clinical data, procedural details, and data from the most recent follow-up including AF recurrence post 90-day blanking period were recorded. Recurrence was defined as >30 seconds documented AF, either by 12 lead ECG or by Holter-monitor in the event of symptoms. Results A total of 27 patients were treated using vHPSD with the QDOT Micro catheter between January 2023 and January 2024. Patient characteristics are outlined in table 1. At the time of procedure, 41% of patients had a prior electrical cardioversion and 67% were in sinus rhythm. No patients had any accessory pulmonary veins and 22.2% had a common left pulmonary vein ostium. Procedures were carried out using conscious sedation in 37% of cases, and under general anaesthetic in all other cases. A CTI line was performed in 33% of cases for documented atrial flutter. Average procedural time was 163 ± 44 minutes with an average fluoroscopy time of 22.3 ± 14.7 minutes. For all patients, a hybrid approach was undertaken with QMODE+ for the posterior wall and QMODE for the anterior wall. Ablation data is given in table 2. All 4 pulmonary veins were isolated in all cases. First pass isolation (FPI) was 69.2% in the left pulmonary veins (LPVs) and 73.1% in the right pulmonary veins (RPVs). Gap locations for failed FPI are shown in figure 1. Of note, there were 6 (37.5%) gaps in total found on the carina. No gaps were found on the anterior wall of the LPVs. QMODE+ was used for 75% of the LPV touch-ups and 50% of the RPV touch-ups. The safety profile demonstrated 2 (7.4%) pericardial effusions requiring percutaneous drainage and no other complications. Freedom from AF post 6 months was 83.3% among the 18 patients (67%) who had a clinic follow-up in this time. Conclusion The QDOT Micro catheter resulted in good outcomes from ablation with a 100% acute efficacy and 83.3% 6-month efficacy, comparable to conventional RF strategy. Gaps in FPI were most likely found at the carinas. Procedural time, including pre and post ablation care, was under 3 hours. The safety profile was reasonable, but the higher-than-expected rate of pericardial effusion requires further investigation. Expansion of the study with more patients and longer follow-ups is pending. Conflict of Interest No known conflicts

Abstract Introduction Premature ventricular contraction (PVC) is a frequently encountered finding in routine ECGs, that in certain individuals may be followed by reduction in ejection fraction (EF). This may be improved or even reversed with a medical or interventional reduction of ectopic burden. Objective The primary objective of this study is to assess the potential effectiveness of cardiac ablation in suppressing PVC and subsequently enhancing the EF. Further we aim to establish predictive factors of the success of the intervention. Methods In a retrospective data analysis at a single medical centre, we examined records of 116 patients who underwent ectopic ablation, with 10 patients having more than 1 ablation. Demographic information, heart-related conditions along with the presence of a scar on MRI, was collected. The study also recorded pre- and post-procedure PVC burden and EF measurements. Results Demographics and procedural details are in table 1. It was found that patients participating in this study were predominantly male (66.4%), on average 60.1 (± 13.6) years old, overweight (BMI 29.8 ± 5.4) with no additional heart disease (56%) and no scarring on MRI (55%).The PVC burden before ablation (27.9 ± 12.7) significantly reduced to 8.0 ± 11.2 post-ablation (p < 0.005), marking an average relative reduction of 68.1% (± 44.1%). Successful interventions, defined by a reduction exceeding 50%, were observed in 79% of patients. The EF increased from 39.6 ± 8.9 to 47.5 ± 10.7 post-ablation (p < 0.005), corresponding to an average increase by 8.4 ± 8.5. Notably amongst the patients who had a successful ablation, 36% of patients achieved normalized EF (>55%) and 42% showed an improvement of at least 5%. A strong correlation emerged between the relative change in PVC and the ejection fraction measured after ablation, with an increase by 0.10 for every percent reduction (p < 0.00). The relative increase in the EF% was significantly higher in patients where the PVC burden was reduced by at least 50% (figure 1). Linear fixed effect modelling explored the influence of patient characteristics on the model. Patients with higher BMI had a lower EF after ablation with same relative reduction in PVC (p < 0.03). Similarly, a scar on MRI and associated heart condition was associated with reduced improvement in ejection fraction (p < 0.02). Also, for every increase in age patients had a reduction of 0.2 EF after ablation (p < 0.01). Right heart PVC’s were ablated more successfully, and had higher EF post ablation (p < 0.01). Conclusion In conclusion, reduction in PVC burden increases the EF after treatment. Increasing BMI, age and presence of associated heart disease can negatively impacted LVEF post ablation. Further research could improve the model that predicts improvement in LV function post successful PVC ablation.Figure 1Table 1

BACKGROUND A novel aggregated multiposition noncontact mapping (AMP-NCM) algorithm is proposed to diagnose cardiac arrhythmias. OBJECTIVE The purpose of this study was to computationally determine an accuracy threshold and to compare the accuracy and clinical utility of AMP-NCM to gold standard contact mapping. METHODS In a cellular automata model, the number of catheter positions and chamber coverage were varied to establish accuracy requirements for clinically relevant AMP-NCM. This guided the clinical study protocol. In a prospective cohort of patients with atrial tachycardia (AT), noncontact mapping (NCM) recordings from a single position (SP) and multiple positions were compared to contact mapping with a high-density multipolar catheter using morphology and timing differences of reconstructed signals. Identification of AT mechanisms and ablation targets using both AMP-NCM and contact mapping were randomly evaluated by 5 blinded reviewers. RESULTS AMP-NCM accuracy was asymptotic at 60 catheter positions in computational modeling. Twenty patients (age 65 +/- 12 years; 19 male) with 26 ATs (5 focal, 21 reentrant) were studied. Morphologic correlation of signals derived from AMP-NCM was significantly better than those from SP-NCM compared to contact signals (median 0.93 vs 0.76; P <.001). AMP-NCM generated maps more rapidly than contact mapping (3 +/- 1 minutes vs 13 +/- 6 minutes; P <.001) and correctly diagnosed AT mechanisms in 25 of 26 maps (96%). Overall, 80% of arrhythmia mechanisms were correctly identified using AMP-NCM by blinded reviewers. CONCLUSION Once 60 catheter positions were achieved, AMP-NCM successfully diagnosed mechanisms of AT and identified treatment sites equal to gold standard contact mapping in 3 minutes of procedural time.

Background Over the last 20 years various techniques have been developed striving for safer and more durable pulmonary vein isolation (PVI). The popularity and uptake of ‘single-shot’ strategies, which by their nature are simpler and quicker, has risen in line with the growing worldwide prevalence of AF and the concomitant requirement to simplify and streamline AF ablation service delivery. The most commonly used single-shot techniques are pulmonary vein ablation catheter (PVAC) and cryoballoon. Head-to-head assessment of outcomes of new-generation cryoballoon vs PVAC gold has never before been performed. Objective Evaluate the safety and efficacy of PVAC gold vs cryoballoon in an unselected population undergoing de-novo ablation for persistent or paroxysmal atrial fibrillation (AF) at Royal Papworth Hospital (RPH). Method Retrospective, single-centre study of consecutive AF ablations at RPH over a one year period. Demographic, procedural and outcome data were analysed. Complications were defined as any adverse procedure-related event. Success was defined as freedom from symptoms or demonstrable arrhythmia after 12 months following an initial 3-month blanking period. The consultant performing the procedure determined the ablation method used. Cases performed using point-by-point techniques or AcQMap were excluded from analysis. Analysis of parametric continuous data were performed using Student’s t-tests, whilst categorical data were compared using the χ2 test. A two-tailed probability level of <0.05 was considered significant. Paroxysmal and persistent AF groups were examined separately due to the well-recognised differences in long-term outcome between the two entities. Results Over the study period 329 first-time PVI procedures were performed. 131 (39.8%) were performed using cryoballoon (106 [78.6%] of which were for pAF) and 75 (22.8%) using PVAC (62 [82.7%] for pAF). The average age was 60.4 ± 10 years and 69.6% of patients were male. There was no significant difference in age, sex, left atrial diameter or cardiovascular co-morbidity profile between different ablation technique groups (table 1). Procedure times were similar between interventions (127 vs 117 mins, p=0.79). Acute vein isolation was achieved in 96.9% of cryoballoon patients and 98.7% of PVAC patients (p=0.88). 12-month freedom from symptomatic AF was not significantly different between cryoballoon and PVAC (75.7 vs 78.6%, p=0.99 for paroxysmal AF; 75.0% vs 83.3%, p=0.80 for persistent AF) (figure 1). Overall complication rate was 1.9%, and similar between groups (table 2). A pseudoaneurysm occurred following a PVAC case requiring surgical intervention. One case each of phrenic nerve palsy, right leg numbness (due to local infiltration of local anaesthetic around the femoral nerve) and air embolism were associated with cryoablation. All resolved within hours, did not require intervention and did not delay discharge. No long-term sequelae were seen. Conclusions PVAC and cryoballoon AF ablation appear equally efficacious with similar procedure times in an unselected population. Both were associated with a low adverse event rate. Conflict of Interest nil

Background: Over the last 20 years various techniques have been developed striving for safer and more durable pulmonary vein isolation (PVI). The three most commonly used tools are pulmonary vein ablation catheter (PVAC) and cryoballoon ('single-shot' techniques), and point-by-point (PBP) radio-frequency ablation using 3D electroanatomical mapping (EAM). Objective: Evaluate the safety and efficacy of the different techniques in an unselected population un-dergoing de-novo ablation for persistent or paroxysmal atrial fibrillation (AF) at Royal Papworth Hospital (RPH). Method: Retrospective, single-centre study of consecutive AF ablations at RPH between March 2017 and April 2018. Demographic, procedural and outcome data were analysed. Results: Over the study period 329 first-time PVI procedures were performed. 37.4% were performed using PBP, 39.8% using cryoballoon and 22.8% using PVAC. There was no significant difference in age or sex between different ablation technique groups. 238 procedures were performed for paroxysmal AF and 91 for persistent AF. A higher proportion of the persistent cases were performed using point-by-point techniques compared to paroxysmal cases (58.2% vs 29.0%, p < 0.05). Procedural times were significantly longer in the group undergoing PBP ablation compared to cry-oballoon or PVAC. However, there was no statistically significant difference in 12-month freedom from symptomatic AF or procedural complications between the groups. Conclusions: PBP, PVAC and cryoballoon AF ablation all appeared equally efficacious in an unselected population, though PVAC and cryoballoon procedures were shorter. All procedures were associated with a low adverse event rate. Prospective examination is required to substantiate this finding. (C) 2021 Cardiological Society of India. Published by Elsevier B.V.

Introduction Major advancements have been made in the design of pacing leads to improve electrical performance and patient safety. However, despite significant progress, pacing leads have remained the most vulnerable components of transvenous pacing systems. The incidence of complications resulting from the insertion of such devices ranges from 3% to 7% and lead perforation is a relatively rare complication seen at 0.1– 0.8% of the cases.

AIMS The very long-term outcome of patients who survive the first few years after receiving cardiac resynchronization therapy (CRT) has not been well described thus far. We aimed to provide long-term outcomes, especially with regard to the occurrence of sudden cardiac death (SCD), in CRT patients without (CRT-P) and with defibrillator (CRT-D). METHODS AND RESULTS A total of 1775 patients, with ischaemic or non-ischaemic dilated cardiomyopathy, who were alive 5 years after CRT implantation, were enrolled in this multicentre European observational cohort study. Overall long-term mortality rates and specific causes of death were assessed, with a focus on late SCD. Over a mean follow-up of 30 months (interquartile range 10-42 months) beyond the first 5 years, we observed 473 deaths. The annual age-standardized mortality rates of CRT-D and CRT-P patients were 40.4 [95% confidence interval (CI) 35.3-45.5] and 97.2 (95% CI 85.5-109.9) per 1000 patient-years, respectively. The adjusted hazard ratio (HR) for all-cause mortality was 0.99 (95% CI 0.79-1.22). Twenty-nine patients in total died of late SCD (14 with CRT-P, 15 with CRT-D), corresponding to 6.1% of all causes of death in both device groups. Specific annual SCD rates were 8.5 and 5.8 per 1000 patient-years in CRT-P and CRT-D patients, respectively, with no significant difference between groups (adjusted HR 1.0, 95% CI 0.45-2.44). Death due to progressive heart failure represented the principal cause of death (42.8% in CRT-P patients and 52.6% among CRT-D recipients), whereas approximately one-third of deaths in both device groups were due to non-cardiovascular death. CONCLUSION In this first description of very long-term outcomes among CRT recipients, progressive heart failure death still represented the most frequent cause of death in patients surviving the first 5 years after CRT implant. In contrast, SCD represents a very low proportion of late mortality irrespective of the presence of a defibrillator.

A 67-year-old man presented to the emergency department with sudden onset of severe presyncope. He reported that he had a permanent pacemaker implanted in 2006 following atrioventricular node ablation for persistent atrial fibrillation (AF). After suffering increasing shortness of breath, he underwent upgrade to cardiac resynchronisation therapy (CRT) in 2016. He denied any recent falls, interventions or changes in medication. ECG monitoring showed AF with a broad ventricular escape rhythm at around 25 bpm with pauses of up to 3 s. Placement of a magnet over the device resulted in pacing (figure 1A). The implanted device (Medtronic Syncra C2TR01) was interrogated (figure 1B), and a chest radiograph was obtained (figure 2). Figure 1(A) Twelve-lead ECG demonstrating intrinsic rhythm and pacing after application of magnet. (B) Device interrogation with right ventricular threshold test.Figure 2(C) Anteroposterior chest radiograph demonstrating lead position on admission.QuestionWhat was the cause of this presentation?Noise oversensing on the right ventricular (RV) lead due to lead fracture.The RV septal lead has displaced into the right atrial (RA).RA and RV leads were switched in the can during the CRT upgrade.Increase in threshold of RV and left ventricular (LV) leads resulting in loss of capture.

Introduction The widely accepted model for AF ablation involves overnight hospital stay post-procedure. Given the rising incidence of AF and number of AF ablations performed, streamlining of practice to minimise overnight stay could result in a significant reduction in waiting list times and procedure-related healthcare expenditure. Day case AF ablation has been carried out at Royal Papworth Hospital (RPH) since early 2017. We evaluated the feasibility, safety and efficacy of day case AF ablation at RPH. Method Retrospective, single-centre study of 452 consecutive AF ablations in 448 patients at RPH between March 2017 and April 2018. Ablation method was selected at the operator’s discretion. Vitamin K antagonists were continued and direct oral anticoagulants withheld for one dose pre-procedure in line with departmental policy. Ultrasound was not routinely used for femoral venous puncture. Haemostasis post-sheath removal was achieved with manual pressure. The consultant listing the patient at initial assessment subjectively determined suitability for day case. Complications were defined as any adverse procedure-related event. Success was defined as freedom from symptoms or demonstrable arrhythmia after 6 months following an initial 3-month blanking period. Results Over the study period 129 out of 452 (28.5%) were planned day cases. Of these 128 (99.2%) were discharged on the same day; one patient was admitted due to late finish. 40 were performed as day cases despite being originally listed as inpatient procedures. Demographic and procedural data are summarised in table 1. There was no significant difference in age or sex between the groups. Of note, day case procedures were significantly shorter, more likely to commence in the morning and less likely to require general anaesthetic than overnight stays. Patients listed as day cases also had less far to travel. Procedural outcomes are summarised in table 2. Overall complication rate was 3.3%, with no significant difference between groups. One planned day case was complicated by intraprocedural phrenic nerve palsy from which a full recovery was made and another by transient migraine. A further case resulted in atrio-oesophageal fistula and death 3 weeks post-discharge. One patient discharged the same day despite planned overnight stay presented to his local DGH 3 days later with pulmonary oedema. Follow up data was available for 448 cases (99.1%). Procedural success rates were comparable between groups. At a cost of circa £400 for an overnight stay in RPH the overall cost saving attributable to providing AF ablation as a day case was £67,200 over the 13 month period. Conclusion Day case AF ablation is safe and efficacious even without strict standardisation of patient selection or procedural protocols in a high volume centre. Substantial reduction in healthcare expenditure can be achieved with more widespread implementation of ambulatory AF ablation. Conflict of Interest nil

Women traditionally have been and are still underrepresented in research in many important areas of cardiology, and guideline recommendations which also encompass women are mostly based on research conducted predominantly in men. However, there is plausible cause to believe that sex may have a potential influence on the benefit derived from the implantable cardioverter-defibrillators (ICD), alone or in association with cardiac resynchronization therapy. We assessed the possible relationship between sex and outcome with ICD implantation in the setting of primary prevention, by pooling the results of MUSTT, MADIT-II, DEFINITE, COMPANION, SCD-HeFT and DANISH trials in a meta-analysis. We pooled results for female and male patients separately. The results suggest that women as a group do not seem to obtain a significant survival benefit from the primary prevention ICD, contrary to men. This in turn may also have contributed to a relative underestimation of the ICD benefit among males when looking at the results in total. It is time for the medical and research communities to actively question the presumed overarching benefit of ICDs irrespective of sex and engage in systematic scientific efforts to definitively evaluate the value of this intervention in women.

OBJECTIVE:In patients indicated for cardiac resynchronisation therapy (CRT), the choice between a CRT-pacemaker (CRT-P) versus defibrillator (CRT-D) remains controversial and indications in this setting have not been well delineated. Apart from inappropriate therapies, which are inherent to the presence of a defibrillator, whether adding defibrillator to CRT in the primary prevention setting impacts risk of other acute and late device-related complications has not been well studied and may bear relevance for device selection.METHODS:Observational multicentre European cohort study of 3008 consecutive patients with ischaemic or non-ischaemic dilated cardiomyopathy and no history of sustained ventricular arrhythmias, undergoing CRT implantation with (CRT-D, n=1785) or without (CRT-P, n=1223) defibrillator. Using propensity score and competing risk analyses, we assessed the risk of significant device-related complications requiring surgical reintervention. Inappropriate shocks were not considered except those due to lead malfunction requiring lead revision.RESULTS:Acute complications occurred in 148 patients (4.9%), without significant difference between groups, even after considering potential confounders (OR=1.20, 95% CI 0.72 to 2.00, p=0.47). During a mean follow-up of 41.4±29 months, late complications occurred in 475 patients, giving an annual incidence rate of 26 (95% CI 9 to 43) and 15 (95% CI 6 to 24) per 1000 patient-years in CRT-D and CRT-P patients, respectively. CRT-D was independently associated with increased occurrence of late complications (HR=1.68, 95% CI 1.27 to 2.23, p=0.001). In particular, when compared with CRT-P, CRT-D was associated with an increased risk of device-related infection (HR 2.10, 95% CI 1.18 to 3.45, p=0.004). Acute complications did not predict overall late complications, but predicted device-related infection (HR 2.85, 95% CI 1.71 to 4.56, p<0.001).CONCLUSIONS:Compared with CRT-P, CRT-D is associated with a similar risk of periprocedural complications but increased risk of long-term complications, mainly infection. This needs to be considered in the decision of implanting CRT with or without a defibrillator.

BACKGROUND Patients with nonischemic dilated cardiomyopathy (DCM) may be at lower risk for ventricular arrhythmias compared with those with ischemic cardiomyopathy (ICM). In addition, DCM has been identified as a predictor of positive response to cardiac resynchronization therapy (CRT).OBJECTIVES The aim of this study was to investigate the impact of an additional implantable cardioverter-defibrillator over CRT, according to underlying heart disease, in a large study group of primary prevention patients with heart failure.METHODS This was an observational, multicenter, European cohort study of 5,307 consecutive patients with DCM or ICM, no history of sustained ventricular arrhythmias, who underwent CRT implantation with (n = 4,037) or without (n = 1,270) a defibrillator. Propensity-score and cause-of-death analyses were used to compare outcomes.RESULTS After a mean follow-up period of 41.4 +/- 29.0 months, patients with ICM had better survival when receiving CRT with a defibrillator compared with those who received CRT without a defibrillator (hazard ratio for mortality adjusted on propensity score and all mortality predictors: 0.76; 95% confidence interval [CI]: 0.62 to 0.92; p = 0.005), whereas in patients with DCM, no such difference was observed (hazard ratio: 0.92; 95% CI: 0.73 to 1.16; p = 0.49). Compared with recipients of defibrillators, the excess mortality in patients who did not receive defibrillators was related to sudden cardiac death in 8.0% among those with ICM but in only 0.4% of those with DCM.CONCLUSIONS Among patients with heart failure with indications for CRT, those with DCM may not benefit from additional primary prevention implantable cardioverter-defibrillator therapy, as opposed to those with ICM. (C) 2017 by the American College of Cardiology Foundation.

Introduction With increasing numbers and complexity of implantable devices, the need for lead extraction is also increasing. There is little UK data available on clinical outcomes. We compiled a multi-centre registry of patients undergoing lead extraction to investigate predictors of success and complications. Methods Data on all cases at three UK tertiary centres (St. Barts and The Heart Hospital London and Papworth Hospital Cambridge) were collected over 18 months. Cases where leads were >1 year in age or where specialist extraction equipment was used were included (cases=137, leads=268). Results 69% of patients were male, age 66±16 years (mean±SD). Devices extracted were single chamber PPMs (5%), dual chamber PPMs (42%), CRTPs (6%), single chamber ICDs (6%), dual chamber ICDs (17%) and CRTDs (24%). 76% of ICD leads were dual coil. Number of leads extracted per patient was 2.0±1.0 and time from implantation was 8.3±11.1 years. Leads were extracted using simple traction (39%), traction with locking stylets alone (8%) or dilator sheaths (5%), bidirectional cutting sheaths (38%) or laser (10%). Only 2% of cases required additional femoral access. Specialist equipment was preferentially used for older leads (10.4±13.1 vs 5.2±5.8 years, p<0.001) and for ICD leads (84% vs 53%, p<0.001). The rate of major procedural adverse events (AE) leading to death or emergent surgery was 2.2%, major AEs unrelated to the procedure was 5.8% and minor AEs was 8.7%. Predictors of AEs include patient age (77±28 vs 66±15 years, p=0.05), the age but not type or number of lead (14.8±24.5 vs 7.2±6.0 years, p=0.01), systemic infectiona(31 vs 8%, p<0.001), increased creatinine level (142±111 vs 108±23 µmol/L, p=0.011), decreased haemoglobin level (109±23 vs 123±24 g/L, p=0.001) and use of assisted traction or laser over simple traction or mechanical cutting sheathsb (p=0.001) – see Table. Complete extraction was achieved in 95.5% of leads, with only 2.2% with >4 cm of lead remaining in situ. Predictors of procedural failure include age but not type or number of leads (11.1±8.6 vs 8.3±11.3 years, p=0.05), systemic infectionc(24 vs 3%, p<0.001) and increased creatinine (162±126 vs 108±66 µmol/L, p=0.012). Laser extraction resulted in 100% success in removing leads. Gender, procedure duration, fluoroscopy time and dose, use of general anaesthesia or temporary pacing was independent of extraction technique and outcome. Discussion This is the first UK prospective multi-centre study of lead extraction data comparing extraction techniques. Overall there is a low major complication and high success rate with the use of either simple traction or specialist equipment. From our findings, high risk cases can be identified pre-procedure to allow adequate case planning. Laser extraction is clinically effective but is associated with a higher complication rates compared with mechanical cutting sheaths.

AIM:There is controversy and sparse data on whether substrate based techniques in addition to pulmonary vein isolation (PVI) confer benefit in the catheter ablation of persistent atrial fibrillation (AF), especially if long standing. We performed an observational study to assess whether substrate based ablation improved freedom from atrial arrhythmia.METHODS:A total of 286 patients undergoing first ablation procedures for persistent AF with PVI only(n = 79), PVI plus linear ablation(n = 85), or PVI plus complex fractionated electrogram (CFAE) and linear ablation(n = 107) were followed. Primary end point was freedom from atrial arrhythmia at one year.RESULTS:Mean duration of pre-procedure time in AF was 28+/-27 months.There were no differences in baseline characteristics between groups except a higher proportion of patients with a severely dilated LA in those receiving PVI+CFAEs+lines. Freedom from atrial arrhythmia was higher with a PVI+CFAE+lines strategy then for PVI alone (HR 1.56, 95% CI: 1.04-2.34, p=0.032) but was not higher with PVI+lines. Benefit of substrate modification was conferred for preprocedure times in AF of over 30 months. The occurrence of atrial tachycardia was higher when lines were added to the ablation strategy (HR 0.08, 95% CI: 0.01-0.59, p=0.014). Freedom from atrial arrhythmia at 1 year was higher with lower patient age, use of general anaesthetic (GA), normal or mildly dilated left atrium and decreasing time in AF.CONCLUSIONS:In patients with long standing persistent AF of over 30 months duration,CFAE ablation resulted in improved freedom from atrial arrhythmia. Increased freedom from atrial arrhythmia occurs in patients who are younger and have smaller atria, and with GA procedures. Linear ablation did not improve outcome and resulted in a higher incidence of atrial tachycardia.

Barra, Sergioa; Yu, Emmaa,b; Khan, Fakharc; Dutka, Davidb; Virdee, Munmohana Author Information

Introduction The outcome of persistent atrial fibrillation (PeAF) ablation remains suboptimal and procedures may be long and painful. Little evidence is available on outcome for procedures under general anaesthetic (GA) compared to conscious sedation (CS). We performed a single-centre observational study to assess whether use of GA in PeAF ablation improved outcome and was cost-effective. Methods 292 patients undergoing first ablation procedures for PeAF by radio-frequency point-by-point technique under CS (n=220) or GA (n=72) were followed. End points were freedom from recurrence of atrial arrhythmia and freedom from listing for repeat ablation at 18 months. Clinical assessments, 12 lead ECGs and 24 hour Holter monitors were obtained at baseline and at 3, 6, 12 and 18 months. Results Baseline characteristics were not significantly different between groups. Freedom from atrial arrhythmia was higher in patients under GA rather than CS (63.9% vs 42.3%, HR 1.87, 95% CI: 1.23 to 2.86, p=0.002) (figure 1A). There was no difference in procedure time and ablation time between groups. There were no complications resulting from use of GA; 5 cases under CS were hindered by airway problems, agitation or pain. Significantly fewer GA patients were listed for repeat procedures (29.2% vs 42.7%, HR 1.62, 95% CI: 1.01 to 2.60, p=0.044 (figure 1B)). Of patients who had arrhythmia recurrence but did not undergo repeat ablation, main reasons were: only occasional recurrences of paroxysmal AF (PAF) (39%), feeling subjectively better despite continuing AF (20%), or low chance of success from further procedures (17%) (figure 2). Multivariate Cox regression analysis found a higher freedom from atrial arrhythmia with use of GA, as well as for decreasing age, normal LA size and decreasing time in AF pre-procedure. Decreasing age and use of GA increased the likelihood of freedom from listing for repeat ablation. A PeAF procedure under GA in our institution is slightly more expensive than under CS (£4406.68 vs £4115.15), but due to lower redo rates, the cost after a maximum of two procedures is lower with GA, with an average saving of £178.88 per patient. Conclusions Using GA to perform PeAF ablation is both clinically and financially effective. Patient immobility leads to improved accuracy of mapping and catheter stability, and optimises lesion quality. Ablating during apnoea has been shown to improve contact force (1) and a single previous study has demonstrated better outcomes for paroxysmal AF ablation under GA (2). However GA may be of particular use for PeAF, where more extensive substrate ablation may be employed, procedures last longer and DCCV is often required. References . Kumar S, et al. Heart Rhythm2012;9:1041–1047. . Di Biase L, et al. Heart Rhythm2011;8:368–372.