Guy Haywood

Long‐Term Outcomes Following High Intensity Focused Ultrasound Ablation for Atrial Fibrillation

The aim of this study is to assess the safety and efficacy of the Epicor high intensity focused ultrasound (St. Jude, Inc.®, Minneapolis, MN, USA) system using seven‐day ambulatory electrocardiogram (ECG) monitoring over a two‐year follow‐up period.

“Double” Potentials Define Linear Lesion Conduction Block Using A Novel Mapping/Linear Lesion Ablation Catheter

Introduction: A novel mapping/ablation catheter using a coaxially ablation electrode (E) that is moveable between distal and proximal ring electrodes along its shaft was used to create a linear lesion over the cavotricuspid isthmus (CTI) and bidirectional block in 32 patients (21 men; age 38–79 years) undergoing ablation for counterclockwise atrial flutter.

Biventricular pacing in heart failure: update on results from clinical trials

Biventricular pacing or resynchronisation therapy is a non-pharmacological therapy for patients with chronic heart failure. Since being originally described in 1994, biventricular pacing has become a subject of intense interest and investigation. This review analyses the results reported in observational series and randomised trials, and seeks to answer two questions. If it works, why does it work? Which heart failure patients will it benefit?

Transseptal left ventricular lead placement using snare technique.

Background:  Coronary sinus (CS) lead placement for cardiac resynchronization therapy has a failure rate of ∼5–10%. Here we describe a way of implanting an endocardial left ventricular (LV) lead via a transseptal puncture (TSP), using a GooseNeck snare and active fixation lead.

Can atrial fibrillation with a coarse electrocardiographic appearance be treated with catheter ablation of the tricuspid valve-inferior vena cava isthmus? Results of a multicentre randomised controlled trial

Objective: To see if strategy of ablating the tricuspid annulus–inferior vena cava isthmus (TV–IVC) is superior to electrical cardioversion to prevent recurrences in patients with coarse atrial fibrillation. Design: Prospective randomised controlled multicentre study. Setting: Four tertiary referral hospitals in the UK. Patients: 57 patients with persistent coarse atrial fibrillation (irregular P waves ⩾0.15 mV in ⩾1 ECG lead). Interventions: Patients were randomised to receive external cardioversion (group A, n = 30) or TV–IVC ablation +/− DC cardioversion (group B, n = 27). Main outcome measures: Cardiac rhythm, scores on quality of life and symptom questionnaires were assessed at 4, 16 and 52 weeks after the procedure. Results: 20 (67%) patients in group A and 19 (70%) patients in group B were in sinus rhythm immediately after their index procedure. At 4, 16 and 52 weeks, the number of patients in sinus rhythm were 5, 3 and 2 in group A and 3, 3 and 1 in group B (p = NS). The quality of life and symptom questionnaire scores were similar in the two groups at each period of follow-up, although they were significantly better for sinus rhythm than for atrial fibrillation at each follow-up visit. Conclusions: As a first-line strategy, TV–IVC ablation offers no advantages over direct current cardioversion for the management of coarse atrial fibrillation.

The use of an esophageal catheter to check the results of left atrial posterior wall isolation in the treatment of atrial fibrillation

Left atrial posterior wall isolation (LAPWI) via catheter, surgical, and hybrid techniques is a promising treatment for persistent atrial fibrillation (PersAF). We investigated whether confirmation of LAPWI can be achieved using an esophageal pacing and recording electrode.

A novel approach to mapping the atrial ganglionated plexus network by generating a distribution probability atlas: KIM et al.

The ganglionated plexuses (GPs) of the intrinsic cardiac autonomic system are implicated in arrhythmogenesis. GP localization by stimulation of the epicardial fat pads to produce atrioventricular dissociating (AVD) effects is well described. We determined the anatomical distribution of the left atrial GPs that influence atrioventricular (AV) dissociation.

37 Thromboembolic events in left ventricular endocardial pacing: long-term outcomes from a multicentre uk registry

Background Endocardial left ventricular (LV) pacing is an effective alternative in patients with failed coronary sinus lead. However, the major concern is the unknown long-term thromboembolic risk and much of the data has come from a small number of centres. We examined the safety and efficacy of endocardial LV pacing across 4 UK centres, to determine the long-term thromboembolic risk. Methods and Results Independent prospective registries from four UK centres were combied to include 68 consecutive patients from 2010–2015. Medical records were reviewed and patients were contacted for follow-up. Thromboembolic events were confirmed on imaging. Baseline patient demographics are shown in Table 1.Abstract 37 Table 1 Baseline demographics 65% patients were already anticoagulated (39 AF, 1 DVT, 2 prosthetic valve, 2 previous LV thrombus). Mean CHADS2VASC2 score for the cohort was 3.5. 44% patients had trans-ventricular LV lead. The mean procedure and fluoroscopy times were 200±120 and 32±28 min. 75% had a silicone-insulated pacing lead. Post-procedure, three patients had haematomas and one had tamponade requiring pericardial drain. Functional improvement was noted with decrease in mean NYHA from 3.5±1 to 2.1±1.2 (p=0.001) and increase in LVEF from 26.5±12 to 34±18.1 (p=0.005) over a 20 month follow-up. Re-do procedure due to lead displacement was required in two patients. One patient underwent system extraction and surgical epicardial lead after device infection. The ischaemic stroke rate, defined as transient or permanent loss of function associated with imaging confirmation of a cerebral infarct in the appropriate territory, occurred in 4 patients (6%) providing an annual event rate of 3.6%. In multivariate analyses, the only significant correlation with the risk of CVA was sub-therapeutic INRs (p<0.01, CI 0.02–0.68, HR 0.12). There was no association between lead material and mode of delivery (transatrial/ventricular) and CVA. 14 patients died during follow-up with mean time to death post-procedure of 20 months. Cause of death was end-stage heart failure in all patients except three (pneumonia in two, knee sepsis). Conclusion Endocardial LV lead in heart failure patients has a good success rate at 1.6 year follow-up. However, it is associated with a modest thromboembolic risk largely due to sub-therapeutic anticoagulation. These results have potential for improvement and newer oral anticoagulants might play a role in this setting.

Persistent Atrial Fibrillation Ablation using the Tip-Versatile Ablation Catheter.

BACKGROUND The mechanisms by which persistent atrial fibrillation (PsAF) develops are incompletely understood. Consequently, the optimal strategy for the ablative management of PsAF remains debated. Current methods are often time consuming, complex and non-reproducible. We assessed the Tip-Versatile Ablation Catheter (T-VAC) technique, a rapidly delivered, empirical technique based on the box-set concept using duty-cycled linear catheter ablation technology. METHODS Forty-four procedures in 40 patients undergoing PsAF ablation with the novel technique were prospectively entered onto a database: 27 de novo. Primary endpoint was freedom from arrhythmia at over two-year follow-up. Secondary endpoints were time to first arrhythmia recurrence, freedom from atrial fibrillation (AF) on and off antiarrhythmic drugs (AAD), procedural and fluoroscopy duration and complication rate. RESULTS At mean follow-up of 33 months, absolute freedom from arrhythmia recurrence was 45% in the de novo group. Overall, at 33 (IQR 24-63) months, 60% of de novo patients were in sustained normal sinus rhythm and a further 15% reported only occasional paroxysms of AF at long-term follow-up. Procedure time was 192±25 mins, total energy delivered 2239±883s and fluoroscopy time was 60±10mins. CONCLUSION In selected patients with persistent AF, a long-term rate of 60% arrhythmia free survival off AAD can be achieved using this novel T-VAC technique.

075 CROCODILE CLIPS: A NEW TECHNIQUE TO DELIVER RADIOFREQUENCY ENERGY THROUGH A BROCKENBROUGH NEEDLE TO FACILITATE DIFFICULT TRANSSEPTAL PUNCTURE. A SINGLE CENTRE EXPERIENCE

Introduction Transseptal puncture (TSP) using a Brockenbrough needle (BN) may be unsuccessful due to a thickened or fibrosed intra-atrial septum. This is especially true of redo procedures which are increasingly encountered. We describe our novel crocodile clip method and experience of using radio-frequency (RF) energy delivered via a standard BN to facilitate difficult TSP. Method and results Our transseptal puncture technique uses an SL1 sheath and BN. The BN is passed up the sheath several times and the sheath is flushed outside the body to protect against shards. The BN is then placed at the fossa ovalis (FO) and position is confirmed via fluoroscopy in standard orthogonal LAO and RAO views. Contrast is injected to visualise tenting, but not staining, of the FO. Puncture is attempted but if unsuccessful with our usual pressure RF energy is used via our crocodile clip technique. A non-sterile ablation catheter is attached to the proximal end of the BN using sterile crocodile clips and using a standard generator in unipolar mode we deliver RF energy of 20 W for up to 10 s at a time. Care must be taken so that the BN and crocodile clips do not touch the skin. Puncture is confirmed by operator feel, fluoroscopy and pressure monitoring. Our Initial cases were trans-oesophageal echocardiography (TOE) guided but later procedures used fluroscopy alone. Our experience of this technique was reviewed using procedural notes and medical records. Over 36 months, 244 left atrial procedures were performed by two operators at our tertiary centre. 49 cases were redo procedures. RF assisted TSP was used in 23 procedures (17 males, 6 females, Mean age 63±10). In total 13/195 (6.66%) of first time procedures had resistant atrial septa compared to 10/49 (20.4%) of ablation procedures requiring redo TSP. TOE was used in 8 cases, 15 were performed with fluoroscopy only. RF was successful after a median 2 bursts (max 4). There were no complications acutely or at follow-up (mean 10.4 months) Conclusions RF is an effective tool to use in challenging TSP and is easily incorporated into normal practice with a variety of AF ablation techniques. Previous case series have described TSP with direct contact between the BN an ablation catheter or a diathermy needle without complication. Our technique only requires a non-sterile reusable catheter and the additional cost is negligible; being only the one-off cost of crocodile clips and their sterilisation between cases.