General anesthesia during atrial fibrillation ablation: Standardized protocol and experience.

BACKGROUND: Most atrial fibrillation (AF) ablations are performed with general anesthesia (GA). The ideal GA protocol is unknown, but it affects ablation outcomes and laboratory utilization. We sought to report a GA protocol used at a high-volume center, with special consideration on efficiency and optimization of mapping and ablation conditions. METHODS: Our protocol consists of propofol as sole anesthetic agent and analgesia with Fentanyl. IV fluids are minimized. After transseptal access, the right phrenic nerve is tagged, rocuronium is given, and redosing avoided. Ventilation is modulated to optimize mapping and ablation. After ablation, isoproterenol is infused for 20 min. After 10 min, propofol is gradually decreased and ventilation set to SIMV 8 breaths/min to promote spontaneous breathing, and then switched to pressure support and propofol stopped. Paralysis is reversed and furosemide given. Patient is extubated once meeting standard criteria. RESULTS: A total of 1286 patients underwent AF ablation from January 2017 to December 2018 using the protocol. Mean age was 66 years (41% paroxysmal AF, CHADS2Vasc 2.6). Total procedure time was 86 min. Median time to extubation was 9 min (first and third quartile 6-16) after procedure completed, with total anesthesia time of 116 min. On average 370 mL of fluids were given by anesthesia. Only one patient who had heart failure required reintubation with no other anesthesia-related complications seen. CONCLUSION: Our GA protocol was specifically designed for AF ablation. It was safe and led to efficient recovery and extubation times. It maximizes laboratory utilization time without compromising safety.

General anesthesia (GA) has been shown to improve outcomes of atrial fibrillation (AF) ablation. However, the ideal anesthetic protocol is unknown. We describe a GA protocol developed by the anesthesiology and electrophysiology team. It considers each phase of the ablation procedure separately in choosing drugs to be used and also careful modulation of ventilator settings to improve mapping and ablation conditions. This GA protocol was then utilized in 1286 patients undergoing AF ablation and it was safe and produced very efficient median time to extubation (9 min).

Human α-amylase present in lower-genital-tract mucosal fluid processes glycogen to support vaginal colonization by Lactobacillus.

Lactobacillus colonization of the lower female genital tract provides protection from the acquisition of sexually transmitted diseases, including human immunodeficiency virus, and from adverse pregnancy outcomes. While glycogen in vaginal epithelium is thought to support Lactobacillus colonization in vivo, many Lactobacillus isolates cannot utilize glycogen in vitro. This study investigated how glycogen could be utilized by vaginal lactobacilli in the genital tract. Several Lactobacillus isolates were confirmed to not grow in glycogen, but did grow in glycogen-breakdown products, including maltose, maltotriose, maltopentaose, maltodextrins, and glycogen treated with salivary α-amylase. A temperature-dependent glycogen-degrading activity was detected in genital fluids that correlated with levels of α-amylase. Treatment of glycogen with genital fluids resulted in production of maltose, maltotriose, and maltotetraose, the major products of α-amylase digestion. These studies show that human α-amylase is present in the female lower genital tract and elucidates how epithelial glycogen can support Lactobacillus colonization in the genital tract.

Venous Vascular Closure System Versus Manual Compression Following Multiple Access Electrophysiology Procedures: The AMBULATE Trial.

OBJECTIVES: This study compared the efficacy and safety of the VASCADE MVP Venous Vascular Closure System (VVCS) device (Cardiva Medical, Santa Clara, California) to manual compression (MC) for closing multiple access sites after catheter-based electrophysiology procedures. BACKGROUND: The VASCADE MVP VVCS is designed to provide earlier ambulatory hemostasis than MC after catheter-based procedures. METHODS: The AMBULATE (A Randomized, Multi-center Trial to Compare Cardiva Mid-Bore [VASCADE MVP] VVCS to Manual Compression in Closure of Multiple Femoral Venous Access Sites in 6 - 12 Fr Sheath Sizes) trial was a multicenter, randomized trial of device closure versus MC in patients who underwent ablation. Outcomes included time to ambulation (TTA), total post-procedure time (TPPT), time to discharge eligibility (TTDe), time to hemostasis (TTH), 30-day major and minor complications, pain medication usage, and patient-reported outcomes. RESULTS: A total of 204 patients at 13 sites were randomized to the device arm (n = 100; 369 access sites) or the MC arm (n = 104; 382 access sites). Baseline characteristics were similar between groups. Mean TTA, TPPT, TTDe, and TTH were substantially lower in the device arm (respective decreases of 54%, 54%, 52%, and 55%; all p < 0.0001). Opioid use was reduced by 58% (p = 0.001). There were no major access site complications. Incidence of minor complications was 1.0% for the device arm and 2.4% for the MC arm (p = 0.45). Patient satisfaction scores with duration of and comfort during bedrest were 63% and 36% higher in device group (both p < 0.0001). Satisfaction with bedrest pain was 25% higher (p = 0.001) for the device overall, and 40% higher (p = 0.002) for patients with a previous ablation. CONCLUSIONS: Use of the closure device for multiple access ablation procedures resulted in significant reductions in TTA, TPPT, TTH, TTDe, and opioid use, with increased patient satisfaction and no increase in complications. (A Randomized, Multi-center Trial to Compare Cardiva Mid-Bore VVCS to Manual Compression in Closure of Multiple Femoral Venous Access Sites in 6 - 12 Fr Sheath Sizes [AMBULATE]; NCT03193021).

Prospective study of atrial fibrillation termination during ablation guided by automated detection of fractionated electrograms.

INTRODUCTION: Complex fractionated atrial electrograms (CFAE) may identify critical sites for perpetuation of atrial fibrillation (AF) and provide useful targets for ablation. Current assessment of CFAE is subjective; automated detection algorithms may improve reproducibility, but their utility in guiding ablation has not been tested. METHODS AND RESULTS: In 67 patients presenting for initial AF ablation (42 paroxysmal, 25 persistent), LA and CS mapping were performed during induced or spontaneous AF. CFAE were identified by an online automated computer algorithm and displayed on electroanatomical maps. A mean of 28 +/- 18 sites/patient were identified (20 +/- 13% of mapped sites), and were more frequent during persistent AF. CFAE occurred most commonly within the CS, on the atrial septum, and around the pulmonary veins. Ablation initially targeting CFAE terminated AF in 88% of paroxysmal AF, but only 20% of persistent AF (P < 0.001). Subsequently, additional ablation was performed in all patients (PV isolation for paroxysmal AF, PV isolation + mitral and roof lines for persistent AF). Minimum follow-up was 1 year. One-year freedom from recurrent atrial arrhythmias without antiarrhythmic drug therapy after a single procedure was 90% for paroxysmal AF, and 68% for persistent AF. CONCLUSIONS: Ablation guided by automated detection of CFAE proved feasible, and was associated with a high AF termination rate in paroxysmal, but not persistent AF. As an adjunct to conventional techniques, it was associated with excellent long-term single procedure outcomes in both groups. Criteria for identifying optimal CFAE sites for ablation, and selection of patients most likely to benefit, require additional study.

Polysorbate 80 and polymyxin B inhibit Stenotrophomonas maltophilia biofilm.

Stenotrophomonas maltophilia is an opportunistic multiple-drug-resistant human pathogen that forms biofilms on implanted medical devices. We examined the potential inhibitory activity of polysorbate 80 and polymyxin B against S. maltophilia. A combination of subMIC polymyxin B and polysorbate 80 was the most effective inhibitor of growth and biofilm formation.

MAGNETIC VT study: a prospective, multicenter, post-market randomized controlled trial comparing VT ablation outcomes using remote magnetic navigation-guided substrate mapping and ablation versus manual approach in a low LVEF population.

PURPOSE: Patients with ischemic cardiomyopathy (ICM) are prone to scar-related ventricular tachycardia (VT). The success of VT ablation depends on accurate arrhythmogenic substrate localization, followed by optimal delivery of energy provided by constant electrode-tissue contact. Current manual and remote magnetic navigation (RMN)-guided ablation strategies aim to identify a reentry circuit and to target a critical isthmus through activation and entrainment mapping during ongoing tachycardia. The MAGNETIC VT trial will assess if VT ablation using the Niobe™ ES magnetic navigation system results in superior outcomes compared to a manual approach in subjects with ischemic scar VT and low ejection fraction. METHODS AND RESULTS: This is a randomized, single-blind, prospective, multicenter post-market study. A total of 386 subjects (193 per group) will be enrolled and randomized 1:1 between treatment with the Niobe ES system and treatment via a manual procedure at up to 20 sites. The study population will consist of patients with ischemic cardiomyopathy with left ventricular ejection fraction (LVEF) of ≤35% and implantable cardioverter defibrillator (ICD) who have sustained monomorphic VT. The primary study endpoint is freedom from any recurrence of VT through 12 months. The secondary endpoints are acute success; freedom from any VT at 1 year in a large-scar subpopulation; procedure-related major adverse events; and mortality rate through 12-month follow-up. Follow-up will consist of visits at 3, 6, 9, and 12 months, all of which will include ICD interrogation. CONCLUSIONS: The MAGNETIC VT trial will help determine whether substrate-based ablation of VT with RMN has clinical advantages over manual catheter manipulation. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT02637947.