Charles Butcher

Left Atrial Appendage Electrical Isolation and Concomitant Device Occlusion to Treat Persistent Atrial Fibrillation: A First-in-Human Safety, Feasibility, and Efficacy Study.

Background—Left atrial appendage (LAA) electric isolation is reported to improve persistent atrial fibrillation (AF) ablation outcomes. However, loss of LAA mechanical function may increase thromboembolic risk. Concomitant LAA electric isolation and occlusion as part of conventional AF ablation has never been tested in humans. We therefore evaluated the feasibility, safety, and efficacy of LAA electric isolation and occlusion in patients undergoing long-standing persistent AF ablation. Methods and Results—Patients with long-standing persistent AF (age, 68±7 years; left atrium diameter, 46±3 mm; and AF duration, 25±15 months) underwent AF ablation, LAA electric isolation, and occlusion. Outcomes were compared with a balanced (1:2 ratio) control group who had AF ablation alone. Among 22 patients who underwent ablation, LAA electric isolation was possible in 20. Intraprocedural LAA reconnection occurred in 17 of 20 (85%) patients, predominantly at anterior and superior locations. All were reisolated. LAA occlusion was successful in all 20 patients. There were no major periprocedural complications. Imaging at 45 days and 9 months confirmed satisfactory device position and excluded pericardial effusion. One of twenty (5%) patients had a gap of ≥5 mm requiring anticoagulation. Nineteen of twenty (95%) patients stopped warfarin at 3 months. Without antiarrhythmic drugs, freedom from AF at 12 months after a single procedure was significantly higher in the study group (19/20, 95%) than in the control group (25/40, 63%), P=0.036. Freedom from atrial arrhythmias was demonstrated in 12 of 20 (60%) and 18 of 20 (90%) patients after 1 and ⩽2 procedures (mean, 1.3), respectively. Conclusions—Persistent AF ablation, LAA electric isolation, and mechanical occlusion can be performed concomitantly. This technique may improve the success of persistent AF ablation while obviating the need for chronic anticoagulation. Clinical Trial Registration—URL: https://clinicaltrials.gov. Unique identifier: NCT02028130.

Outcomes and costs of left atrial appendage closure from randomized controlled trial and real-world experience relative to oral anticoagulation

AIMS The aim of this study was to analyse randomized controlled study and real-world outcomes of patients with non-valvular atrial fibrillation (NVAF) undergoing left atrial appendage closure (LAAC) with the Watchman device and to compare costs with available antithrombotic therapies. METHODS AND RESULTS Registry data of LAAC from two centres were prospectively collected from 110 patients with NVAF at risk of stroke, suitable and unsuitable for long-term anticoagulation (age 71.3 ± 9.2 years, CHADS2 2.8 ± 1.2, CHA2DS2-VASc 4.5 ± 1.6, and HAS-BLED 3.8 ± 1.1). Outcomes from PROTECT AF and registry study LAAC were compared with warfarin, dabigatran, rivaroxaban, apixaban, aspirin, and no treatment using a network meta-analysis. Costs were estimated over a 10-year horizon. Uncertainty was assessed using sensitivity analyses. The procedural success rate was 92% (103/112). Follow-up was 24.1 ± 4.6 months, during which annual rates of stroke, major bleeding, and all-cause mortality were 0.9% (2/223 patient-years), 0.9% (2/223 patient-years), and 1.8% (4/223 patient-years), respectively. Anticoagulant therapy was successfully stopped in 91.2% (93/102) of implanted patients by 12 months. Registry study LAAC stroke and major bleeding rates were significantly lower than PROTECT AF results: mean absolute difference of stroke, 0.89% (P = 0.02) and major bleeding, 5.48% (P < 0.001). Left atrial appendage closure achieved cost parity between 4.9 years vs. dabigatran 110 mg and 8.4 years vs. warfarin. At 10 years, LAAC was cost-saving against all therapies (range £1162-£7194). CONCLUSION Left atrial appendage closure in NVAF in a real-world setting may result in lower stroke and major bleeding rates than reported in LAAC clinical trials. Left atrial appendage closure in both settings achieves cost parity in a relatively short period of time and may offer substantial savings compared with current therapies. Savings are most pronounced among higher risk patients and those unsuitable for anticoagulation.

Evaluation of a novel high-resolution mapping system for catheter ablation of ventricular arrhythmias.

BACKGROUND The mapping of ventricular arrhythmias in humans using a minibasket 64-electrode catheter paired with a novel automatic mapping system (Rhythmia) has not been evaluated. OBJECTIVE The purpose of this study was to evaluate the safety and efficacy of mapping ventricular arrhythmias and clinical outcomes after ablation using this system. METHODS Electroanatomic maps for ventricular arrhythmias were obtained during 20 consecutive procedures in 19 patients (12 with ventricular tachycardia [VT] and 2 with ventricular ectopy [VE]). High-density maps were acquired using automatic beat acceptance and automatic system annotation of electrograms. RESULTS Forty-seven electroanatomic maps (including 3 right ventricular and 9 epicardial maps) were obtained. Left ventricular endocardial mapping by transseptal (n = 13) and/or transaortic (n = 11) access was safe with no complications related to the minibasket catheter. VT substrate maps (n = 14; median 10,184 points) consistently demonstrated late potentials with high resolution. VT activation maps (n = 25; median 6401 points) obtained by automatic annotation included 7 complete maps (covering ≥90% of the tachycardia cycle length) in 5 patients in whom the entire VT circuit was accurately visualized. VE timing maps (n = 8) successfully localized the origin of VEs in all, with all accepted beats consistent with clinical VEs. Over a median follow-up of 10 months, no arrhythmia recurrence was noted in 75% after VT ablation and 86% after VE ablation. CONCLUSION In this first human experience for ventricular arrhythmias using this system, ultra-high-density maps were created rapidly and safely, with a reliable automatic annotation of VT and consistent recording of abnormal electrograms. Medium-term outcomes after ablation were encouraging. Further larger studies are needed to validate these findings.

When Is it Appropriate to Withdraw Cardiac Resynchronization Therapy? Guesses and Evidence∗

In designing clinical trials, investigators consider many factors. The population should have the disease in question and have needs unmet by conventional care that might be improved by intervention. Guessing which clinical variables will identify patients who respond to a therapy, especially when

Algorithms to guide ambulance clinicians in the management of emergencies in patients with implanted rotary left ventricular assist devices

Advances in left ventricular assist device (LVAD) therapy have resulted in increasing numbers of adult LVAD recipients in the community. However, device failure, stroke, bleeding, LVAD thrombosis and systemic infection can be life-threatening emergencies. Currently, four LVAD systems are implanted in six UK transplant centres, each of which provides device-specific information to local emergency services. This has resulted in inconsistent availability and content of information with the risks of delayed or inappropriate decision-making. In order to improve patient safety, a consortium of UK healthcare professionals with expertise in LVADs developed universally applicable prehospital emergency algorithms. Guidance was framed as closely as possible on the standard ABCDE approach to the assessment of critically ill patients.

Response by Panikker et al to Letter Regarding Article, “Left Atrial Appendage Electrical Isolation and Concomitant Device Occlusion to Treat Persistent Atrial Fibrillation: A First-in-Human Safety, Feasibility, and Efficacy Study”

We thank Vroomen et al1 for their letter detailing the benefits of hybrid atrial fibrillation ablation, involving thoracoscopic epicardial ablation combined with endocardial catheter ablation followed by an epicardial left atrial appendage (LAA) clip procedure, performed in an experienced center.2 However, wider adoption of this approach as routine clinical practice is not without concerns. Epicardial LAA closure/excision has been performed for many years although follow-up imaging studies have shown that successful closure using a variety of closure techniques may only range between 0% and 73%. Importantly, a significant proportion of patients with unsuccessful closure had evidence …

Letter by Mareev et al Regarding Article, “Comparative Effectiveness of Implantable Cardioverter Defibrillators for Primary Prevention in Women”

Zeitler et al1 suggest that implantable cardioverter defibrillators (ICDs) exert a similar reduction in mortality in men and women, but their estimate of the absolute reduction in mortality for either sex (≈7.5% at 1 year and 10% by 3 years) far exceeds that observed (about 0% and 5% at 1 and 3 years, respectively)2 in randomized controlled trials (RCTs) These large differences require reconciliation. RCTs could underestimate the impact of interventions in clinical practice. If true, this could have led to the rejection of many useful therapies. Selection criteria for inclusion in RCTs usually result in populations at intermediate risk; patients at low risk who have little to gain are excluded, as …

0092 Clinical risk reduction in simulated settings (CRRISIS): An initial 2-year experience implementing a hospital-wide simulation programme in a cardiothoracic centre

Background The management of patients in a cardiothoracic centre requires effective interaction between clinical care groups. CRRISiS (Clinical Risk Reduction in Simulated Settings) was developed to support this. These high-fidelity, simulation sessions involve the multidisciplinary-team across departments. A debrief structure focussing on human factors and clinical outcomes facilitates a ‘common debrief language’ across departments. We report participant feedback from our first 2 years. Methodology 43 training sessions were delivered across cardiology, transplant, intensive care and cardiothoracic departments. All staff were encouraged to attend and signed consent forms. Sessions commenced with an introduction to crisis resource management principles. A structured, step-wise, immersive simulation followed with events occurring in real time, with staff participating in their clinical roles. Scenarios were based on a previously challenging clinical situation or “never events”. These included cardiac tamponade and fluoroscopic failure during primary angioplasty. Each scenario was followed by a debrief, facilitated by a simulation instructor, reflecting on both clinical and human factors. The simulation team included teaching fellows, resuscitation officers, allied healthcare professionals and consultants. Feedback was collected using Likert Scale. Results 202 responses were analysed (16 physiologists, 13 radiographers, 8 students, 3 healthcare assistants, 7 physiotherapists, 50 nurses, 30 junior doctors, 6 registrars, 6 consultants, 68 other/unknown). Group sizes varied from 4–23 staff. 99.5% agreed/strongly agreed that the scenario felt realistic and they had increased awareness of human factors. 99.2% felt they had increased their clinical knowledge and enhanced inter-professional relationships. 99.5% would recommend to colleagues and like to attend more sessions. Conclusions Implementation of a formal simulation-training programme across a specialist centre is possible. Although it is difficult to assess whether attendance at CRRISiS sessions impacts upon clinical outcomes, candidates have reported improvements in awareness of human factors, clinical knowledge and inter-professional relationships. Moving forward, this may have positive implications for patient care.