BACKGROUND:Pulmonary vein isolation (PVI) using thermal energy-radiofrequency (RF) or cryoablation (CRYO)-is associated with direct myocardial injury and collateral neural damage. In contrast, pulsed electric field (PEF) energy has emerged as a neural-sparing alternative. There is a lack of quantitative data on proportional neural damage resulting from individual ablation energies. OBJECTIVE:To assess the impact of PVI by RF, CRYO and PEF on the release of plasma biomarkers of myocardial and neural damage. METHODS:This study included 85 patients with paroxysmal atrial fibrillation undergoing PVI (age: 61 ± 12 years, 74% males). Ablation was performed with PEF in 32 patients, RF in 23, and CRYO in 30. Peripheral venous blood samples were collected before, immediately after PVI, and the day after the procedure to measure plasma levels of S100 binding protein (S100B), high-sensitivity troponin I (hsTnI), and high-sensitivity troponin T (hsTnT). Groups were compared based on maximum biomarker levels and the (hsTnI/hsTnT)/S100B ratio as an index of cardioselectivity. RESULTS:Following PVI, all energy modalities caused significant myocardial injury, with PEF showing the most pronounced effects (maximum hsTnT: 1476, 958 and 967 ng/L; maximum hsTnI: 12659, 1699 and 8109 ng/L; for PEF, RF and CRYO, respectively). Maximum S100B levels indicating the neural impact were highest in the CRYO group (80, 80 and 190 ng/L for PEF, RF and CRYO, respectively). PEF exhibited the greatest cardioselectivity, as indicated by the highest (hsTnI/hsTnT)/S100B ratio (0.11 ± 0.04, 0.02 ± 0.01 and 0.05 ± 0.05 for PEF, RF and CRYO, respectively). Interestingly, no correlation was observed between S100B release and heart rate acceleration (R = 0.07, p = 0.51). CONCLUSION:PEF is the most cardioselective modality of ablation energy currently available for the treatment of atrial fibrillation. The neuromodulatory effect of PVI on the sinus node appears to be independent of the magnitude of neural damage.

Aims Patients with structural heart disease (SHD) undergoing catheter ablation (CA) for ventricular tachycardia (VT) are at considerable risk of periprocedural complications, including acute haemodynamic decompensation (AHD). The PAINESD score was proposed to predict the risk of AHD. The goal of this study was to validate the PAINESD score using the retrospective analysis of data from a large-volume heart centre. Methods and results Patients who had their first radiofrequency CA for SHD-related VT between August 2006 and December 2020 were included in the study. Procedures were mainly performed under conscious sedation. Substrate mapping/ablation was performed primarily during spontaneous rhythm or right ventricular pacing. A purposely established institutional registry for complications of invasive procedures was used to collect all periprocedural complications that were subsequently adjudicated using the source medical records. Acute haemodynamic decompensation triggered by CA procedure was defined as intraprocedural or early post-procedural (<12 h) development of acute pulmonary oedema or refractory hypotension requiring urgent intervention. The study cohort consisted of 1124 patients (age, 63 +/- 13 years; males, 87%; ischaemic cardiomyopathy, 67%; electrical storm, 25%; New York Heart Association Class, 2.0 +/- 1.0; left ventricular ejection fraction, 34 +/- 12%; diabetes mellitus, 31%; chronic obstructive pulmonary disease, 12%). Their PAINESD score was 11.4 +/- 6.6 (median, 12; interquartile range, 6-17). Acute haemodynamic decompensation complicated the CA procedure in 13/1124 = 1.2% patients and was not predicted by PAINESD score with AHD rates of 0.3, 1.8, and 1.1% in subgroups by previously published PAINESD terciles (<9, 9-14, and >14). However, the PAINESD score strongly predicted mortality during the follow-up. Conclusion Primarily substrate-based CA of SHD-related VT performed under conscious sedation is associated with a substantially lower rate of AHD than previously reported. The PAINESD score did not predict these events. The application of the PAINESD score to the selection of patients for pre-emptive mechanical circulatory support should be reconsidered.

Abstract Funding Acknowledgements Type of funding sources: None. Background The most frequent complications of catheter ablation for atrial fibrillation (AF) are related to vascular access. Purpose Vascular complication rates of ultrasound-guided venipuncture (USGV) were analyzed and compared to historical controls (CTRL) with an anatomical landmark-guided approach. Methods The study cohort included 4646 consecutive patients (2330 and 2316 patients in USGV and CTRL groups, respectively). Clinical characteristics were as follows: age of 61±10 years, 67% males, 66% paroxysmal AF, CHA2DS2-VASc score of 2.0±1.4, 27% reablation, and procedure time of 208±69 min. Both femoral veins were cannulated with 2 and 2 sheaths (7, 11, and 2x 8.5 French) in the majority (>95%) of procedures. Major complications were defined as those requiring intervention (surgery, thrombin injection, or transfusion), or hematoma/bleeding with hemoglobin drop >30g/l, or condition prolonging hospitalization and/or resulting in re-hospitalization. They were extracted from the institutional tracking system for complications of invasive procedures and by a review of medical reports within the first 3 months of follow-up. Results There were 32 (1.38%) vs. 62 (2.66%) major complications related to vascular access in USGV and CTRL groups, respectively (Yates corrected Chi-square P=0.003), i.e. relative reduction of -48% in the USGV group. Surgical intervention was needed in 6 (0.26%) vs. 18 (0.77%) patients, respectively (Fisher exact test P=0.02), i.e. relative reduction of -64% in the USGV group. The differences remained significant after adjustment for baseline clinical characteristics. Multivariate analysis revealed that USGV strategy (P=0.0005), male gender (P=0.003), and less advanced age (P=0.0002) were significantly associated with lower complication rates. Conclusions USGV was associated with a statistically significant reduction of major vascular complications after catheter ablation for AF. This strategy also decreased the need for surgical correction of vascular complications. Ultrasound guidance can be recommended to improve the safety of femoral venous access.

Background Substrate mapping has highlighted the importance of targeting diastolic conduction channels and late potentials during ventricular tachycardia (VT) ablation. State-of-the-art multipolar mapping catheters have enhanced mapping capabilities. The purpose of this study was to investigate whether long-term outcomes were improved with the use of a HD Grid mapping catheter combining complementary mapping strategies in patients with structural heart disease VT. Methods Consecutive patients underwent VT ablation assigned to either HD Grid, Pentaray, Duodeca, or point-by-point (PbyP) RF mapping catheters. Clinical endpoints included recurrent anti-tachycardia pacing (ATP), appropriate shock, asymptomatic non-sustained VT, or all-cause death. Results Seventy-three procedures were performed (33 HD Grid, 22 Pentaray, 12 Duodeca, and 6 PbyP) with no significant difference in baseline characteristics. Substrate mapping was performed in 97% of cases. Activation maps were generated in 82% of HD Grid cases (Pentaray 64%; Duodeca 92%; PbyP 33% ( p = 0.025)) with similar trends in entrainment and pace mapping. Elimination of all VTs occurred in 79% of HD Grid cases (Pentaray 55%; Duodeca 83%; PbyP 33% ( p = 0.04)). With a mean follow-up of 372 ± 234 days, freedom from recurrent ATP and shock was 97% and 100% respectively in the HD Grid group (Pentaray 64%, 82%; Duodeca 58%, 83%; PbyP 33%, 33% (log rank p = 0.0042, p = 0.0002)). Conclusions This study highlights a step-wise improvement in survival free from ICD therapies as the density of mapping capability increases. By using a high-density mapping catheter and combining complementary mapping strategies in a strict procedural workflow, long-term clinical outcomes are improved.

Background: Catheter ablation for complex left-atrial arrhythmia is increasing worldwide with many centres admitting patients overnight. Same-day procedures using conscious sedation carry significant benefits to patients/healthcare providers but data are limited. We evaluated the safety and cost-effectiveness of same-day complex left-atrial arrhythmia ablation. Method: Multi-centre retrospective cohort study of all consecutive complex elective left-atrial ablation procedures performed between January 2011 and December 2019. Data were collected on planned same-day discharge versus overnight stay, baseline parameters, procedure details/success, ablation technology, postoperative complications, unplanned overnight admissions/outcomes at 4-months and mortality up to April 2020. A cost analysis of potential savings was also performed. Results: A total of 967 consecutive patients underwent complex left-ablation using radiofrequency (point-by point ablation aided by 3D-mapping or PVAC catheter ablation with fluoroscopic screening) or cryoballoonablation (mean age: 60.9 +/- 11.6 years, range 23-83 yrs., 572 [59%] females). The majority of patients had isolation of pulmonary veins alone (n = 846, 87%) and most using conscious-sedation alone (n = 921, 95%). Of the total cohort, 414 (43%) had planned same-day procedure with 35 (8%) admitted overnight due to major (n = 5) or minor (n = 30) complications. Overall acute procedural success-rate was 96% (n = 932). Complications in planned overnight-stay/same-day cohorts were low. At 4-month follow-up there were 62 (6.4%) readmissions (femoral haematomas, palpitation, other reasons); there were 3 deaths at mean follow-up of 42.0 +/- 27.6 months, none related to the procedure. Overnight stay costs 350; pound the same-day ablation policy over this period would have saved 310,450 pound. Conclusions: Same-day complex left-atrial catheter ablation using conscious sedation is safe and cost-effective with significant benefits for patients and healthcare providers. This is especially important in the current financial climate and Covid-19 pandemic. (C) 2020 Elsevier B.V. All rights reserved.

Background Cardiologists at Worcestershire Royal Hospital have provided email advice and guidance for local general practitioners. The performance of this service has not been formally evaluated. Methodology Data were collected prospectively throughout 2018 including patient demographics, GP practice, time/date of email and of response, the person responding, the nature of the clinical question and whether admission or clinic appointment was recommended. Patient records were reviewed two months after the email to evaluate outcome. Results In 2018, 2157 email queries were received about patients with a median age of 68 years (IQR 53–77). 52% were male. In total 2145 queries (99.44%) were sent on weekdays, mean of 8.25 per weekday. The median response time was 4 hours 19 minutes (IQR 1.78–17.45 hours), 14.6% received a response in under an hour, 86.1% of queries were responded to within 24 hours and 93.9% within 48 hours. Weekend emails explained the remainder. Overall 91.4% of emails were received between 0800–1700 and 36.2% of responses were sent outside of this time. We estimate 215 consultant hours were taken replying (assuming 6 minutes/email) equivalent to 54 programmed activity (PA) episodes. The most common queries related to interpretation or management of ECGs (44%), ambulatory ECG monitoring (12.5%) or echocardiography (9.2%). In total 73 GP Practices sent emails (mean of 28.6 queries/practice) of which 63 (86.3 %) were from the Worcestershire CCG area. Worcestershire GPs accounted for 97.5% of all queries. Variation exists between individual practices: three did not send any email queries; seven sent only one query over the year and one practice sent 179 queries (8.6% of total). If all practices participated as frequently, the number of emails received would increase five-fold to over 10,000 a year. Of the 10 Cardiology consultants within the deparment, not all participated equally with three consultants replying to 63% of all emails and one replying to 30%. Admission to hospital was recommended in one case and referral to outpatient clinic was recommended in 501 of 2152 cases (23.2%). Of these, a referral was only received within two months in 60.6% of cases. We estimate that this initiative avoided up to 1493 clinic appointments (124 Consultant PA episodes or 2 per week). Potential cost savings to CCG (1493 × £168 for cost of new outpatient consultation) = £250,824. Potential revenue to cardiology for ECG interpretation (44% of 2153 × £25 = £23,683) and for 24 hour holter interpretation 12.5% of 2153 × £45 =£12,110) (Price estimate from NICE Remote ECG interpretation consultancy services for cardiovascular disease MIB152)) Conclusion A cardiology advice and guidance email service is highly efficient use of specialist consultant time with a large number of outpatient clinic appointments being avoided at a cost saving to the CCG. Conflict of Interest None

Vedení antikoagulační léčby v perioperačním období je mnohdy náročným úkolem, který vyžaduje posouzení vztahu mezi tromboembolickým rizikem a rizikem krvácení vyplývajícím ze samotného chirurgického výkonu.Výsledky z velkých randomizovaných studií, které se zabývaly optimálním perioperačním režimem,

AIMS:In patients with severe neurally mediated syncope (NMS), radiofrequency catheter ablation (RFA) of ganglionic plexi (GP) has been proposed as a new therapeutic approach. Cardio-inhibitory response during NMS is usually related to the sinoatrial (SA) and less frequently to atrioventricular (AV) node. Differential effect of GP ablation on SA and AV node is poorly understood.METHODS AND RESULTS:We report a case of a 35-year-old female with frequent symptomatic episodes of advanced AV block treated by anatomically guided RFA at empirical sites of GPs. After RFA at the septal portion of the right atrium-superior vena cava junction, heart rate accelerated from 62 to 91 beats/min and PR interval prolonged from 213 to 344 ms. Sustained first-degree AV block allowed to observe directly the effects of subsequent RFA on the AV nodal properties. Subsequent RFA at right- and left-sided aspects of the inter-atrial septum had no further effect on heart rate and PR interval. Ablation at the inferior left GP was critical for restoration of normal AV conduction (final PR interval of 187 ms). No bradycardia episodes were observed by implantable loop recorder during the follow-up of 10 months and the patient was symptomatically improved.CONCLUSION:This is the first clinical case showing the differential effect of GP ablation on SA and AV nodal function, and critical importance of targeting the GP at the postero-inferior left atrium. The successful procedure corroborates clinical utility of ablation treatment instead of pacemaker implantation in selected patients with cardio-inhibitory NMS.

Background Mitral isthmus is often targeted as a part of stepwise approach during radiofrequency ablation for persistent atrial ablation. Acute success rate in achieving the mitral isthmus block is only modest, late reconduction rate is relatively high and, consequently, incomplete lesion may be proarrhythmic. We describe the first-in-man experience with successful MI ablation by bipolar RF energy delivery. Case presentation A 64-year-old caucasian man after two previous ablation procedures for drug resistant atrial fibrillation in recent four years, which included pulmonary vein isolation and linear left atrial lesions, was referred for the treatment of recurrent perimitral flutter. Despite the third attempt to create bidirectional block at the mitral isthmus region, we were not even able to stop the arrhythmia by aggressive unipolar radiofrequency ablation both from the left atrium and coronary sinus, because of deeply embedded slow conducting channel probably around the vein of Marshall. Arrhythmia was finally terminated and the block was achieved by bipolar radiofrequency ablation between two irrigated-tip catheters positioned at the left atrial endocardium and contralaterally inside the coronary sinus. Conclusion Bipolar radiofrequency energy delivery can be an option for ablation of perimitral flutter resistant to standard unipolar radiofrequency ablation. This may improve clinical outcome of patients undergoing non-pharmacological treatment for persistent atrial fibrillation. The safety and efficacy of this technique has to be confirmed in future studies.

VT Ablation in Patients With Preserved LV Function Introduction Patients with coronary artery disease (CAD), relatively preserved left ventricular ejection fraction (LVEF), and hemodynamically tolerated ventricular tachycardia (VT) may benefit from catheter ablation as the first‐line treatment. Our aim was to analyze the long‐term results of VT ablation in this population. Methods and Results Thirty‐one patients (1 woman, mean age 67 ± 10 years) with CAD, tolerated VT, and LVEF ≥40% underwent catheter ablation as the first‐line treatment of the arrhythmia. Catheter ablation was performed in order to abolish all inducible VTs. An ICD was implanted if sustained VT of any morphology remained inducible after the procedure. The mean LVEF was 48 ± 6% and the mean VT cycle length reached 348 ± 70 milliseconds in the study cohort. Clinical and all inducible VTs were abolished in 90% (28/31) and 58% (18/31) of the patients, respectively. An ICD was subsequently implanted in 42% of cases. Over a mean follow‐up of 3.8 ± 2.9 years, 42% (13/31) patients died. Survival of the patients with or without the ICD was not significantly different (P = 0.47). VT recurrence was observed in 11% (2/18) of patients who had complete elimination of all inducible VTs. No sudden death occurred in patients without the ICD. Conclusions Catheter ablation of VT as the first‐line treatment in patients with CAD and relatively preserved LVEF is a viable strategy. It may prevent implantation of the ICD in a considerable proportion of patients. Abolition of all inducible VTs confers low VT recurrence rate over a long‐term follow‐up.

Unipolar Voltage Mapping in ICM Introduction Following myocardial infarction (MI), left ventricular function is determined by cardiac remodeling occurring in both infarcted and noninfarcted myocardium (NIM). Unipolar voltage mapping may detect remodeling changes in NIM that are associated with the left ventricular ejection fraction (LVEF). We aimed to identify (1) unipolar voltage characteristics in patients with chronic MI, and (2) association of voltage abnormalities with degree of left ventricular dysfunction (LVD). Methods and Results Two groups of patients with ischemic cardiomyopathy (ICM) who underwent LV endocardial mapping during catheter ablation for ventricular tachycardia (VT) between January 2010 and December 2012 were studied. The first group (19 males) had mild to moderate LVD (M‐LVD, LVEF >35%) and was matched for age, sex, infarction size, and infarction location with 10 males who had severe LVD (S‐LVD, LVEF <35%). Both bipolar and unipolar endocardial abnormal voltage areas were measured and compared between groups. Abnormal bipolar area was comparable in both groups (30 ± 8% in the S‐LVD group vs 28 ± 8% in the M‐LVD group; P = 0.5). Total abnormal unipolar voltage area was significantly larger in the S‐LVD group (57 ± 14% vs 43 ± 13%; P = 0.02). The abnormal unipolar voltage area within the normal bipolar voltage area was greater in the S‐LVD group (26 ± 11% vs 15 ± 16%; P = 0.03). In receiver operating characteristic curve analysis, an 18.0% cut‐off value for abnormal unipolar area within NIM identified severe LVD, with 90% sensitivity and 79% specificity (area under the curve 0.821). Conclusions Patients with ICM and severe LVD have larger areas of unipolar voltage abnormality in the noninfarcted tissue than patients with M‐LVD.

BACKGROUND Patients with coronary artery disease (CAD) may have ventricular tachycardia (VT) from a separate nonischemic process. Catheter ablation in these patients can be misguided by abnormalities of coronary arteries.OBJECTIVE To identify (1) the prevalence of unanticipated nonischemic VT in patients with known CAD presenting with VT and (2) the substrate and VT characteristics of this unique subset of patients.METHODS We examined consecutive patients referred for VT catheter ablation who had a history of myocardial infarction and angiography documented CAD with presumed ischemic VT. Patients with low-voltage zones and/or VT origin inconsistent with CAD distribution were included for further analysis.RESULTS Of 732 patients, 9 (1.2%) (7 men; median age 74 years; ejection fraction 30%) fulfilled inclusion criteria. Endocardial left ventricular scar inconsistent with CAD distribution was found in 8 patients. In 1 patient, only epicardial left ventricular scar was found. The distribution of low voltage (<1.5 mV) was predominantly around the aortic and mitral valves. Thirty-one VTs were induced in 8 patients. Most VTs had right bundle branch block (68%); of these VTs, 67% had an R/S transition zone Later than lead V-4 consistent with basal VT origin. Epicardial ablation was necessary in 2 patients. During follow-up (30 [25-39] months), 7 of 9 patients (78%) were free of recurrent VT.CONCLUSIONS A small but important subgroup of patients with CAD and VT has a nonischemic substrate/etiology for VT. The presence of multiple VTs with basal origin suggests a potential nonischemic perivalvular substrate and possible need for epicardial VT ablation.