Baseline left atrial low-voltage area predicts recurrence after pulmonary vein isolation: WAVE-MAP AF results

AIMS

Electro-anatomical mapping may be critical to identify atrial fibrillation (AF) subjects who require substrate modification beyond pulmonary vein isolation (PVI). The objective was to determine correlations between pre-ablation mapping characteristics and 12-month outcomes after a single PVI-only catheter ablation of AF.

METHODS AND RESULTS

This study enrolled paroxysmal AF (PAF), early persistent AF (PsAF; 7 days-3 months), and non-early PsAF (>3-12 months) subjects undergoing de novo PVI-only radiofrequency catheter ablation. Sinus rhythm (SR) and AF voltage maps were created with the Advisor HD Grid™ Mapping Catheter, Sensor Enabled™ for each subject, and the presence of low-voltage area (LVA) (low-voltage cutoffs: 0.1-1.5 mV) was investigated. Follow-up visits were at 3, 6, and 12 months, with a 24-h Holter monitor at 12 months. A Cox proportional hazards model identified associations between mapping data and 12-month recurrence after a single PVI procedure. The study enrolled 300 subjects (113 PAF, 86 early PsAF, and 101 non-early PsAF) at 18 centres. At 12 months, 75.5% of subjects were free from AF/atrial flutter (AFL)/atrial tachycardia (AT) recurrence. Univariate analysis found that arrhythmia recurrence did not correlate with AF diagnosis, but LVA was significantly correlated. Low-voltage area (<0.5 mV) >28% of the left atrium in SR [hazard ratio (HR): 4.82, 95% confidence interval (CI): 2.08-11.18; P = 0.0003] and >72% in AF (HR: 5.66, 95% CI: 2.34-13.69; P = 0.0001) was associated with a higher risk of AF/AFL/AT recurrence at 12 months.

CONCLUSION

Larger extension of LVA was associated with an increased risk of arrhythmia recurrence. These subjects may benefit from substrate modification beyond PVI.

Lesion Index–guided workflow for the treatment of paroxysmal atrial fibrillation is safe and effective – Final results from the LSI Workflow Study

Background

Pulmonary vein isolation (PVI) ablation is a standard therapy for paroxysmal atrial fibrillation (PAF). Lesion Index (LSI) is a metric to guide radiofrequency (RF) ablation using the TactiCath Ablation Catheter, Sensor Enabled with the EnSite Cardiac Mapping System (Abbott).

Objective

This study (NCT-03906461) was designed to capture best practices using LSI-guided catheter ablation to treat PAF subjects in a real-world setting.

Methods

This prospective single-arm observational study enrolled 143 PAF subjects in the United States, Europe, and Japan undergoing de novo PVI with RF ablation. PVI lesions were assigned to 10 anatomically defined segments. Mean LSIs achieved for all lesions were analyzed. Follow-up was conducted between 3–6 months and 12 months after the procedure.

Results

Pulmonary veins were isolated in all subjects. The mean achieved LSI was 4.9, with lower values in Europe (4.4) and Japan (4.5) than the United States (5.5). First-pass success, defined as no gaps requiring touch-up ablation after 20 minutes post isolation, was achieved in 76.2% of subjects. Use of high LSI (≥5) resulted in shorter procedure, RF, and fluoroscopy times and fewer touch-up ablations compared to low LSI (<5). At 12 months, 99.3% of subjects were free from procedure- or device-related serious adverse events and 95.7% (112/117) (35.0% on antiarrhythmic drugs) were free from recurrence and/or a repeat ablation procedure for atrial fibrillation / atrial flutter / atrial tachycardia.

Conclusion

LSI-guided ablation strategies proved safe and effective despite differences in LSI workflows. Use of high LSI values resulted in shorter procedure, RF, and fluoroscopy times and fewer touch-up ablations compared to low LSI.

Inpatient mortality and healthcare resource utilization of nontraumatic intracerebral hemorrhage complications in the US

OBJECTIVE

Nontraumatic, primary intracerebral hemorrhage (ICH) accounts for 2 million strokes worldwide annually and has a 1-year survival rate of 50%. Recent studies examining functional outcomes from ICH evacuation have been performed, but limited work has been done quantifying the incidence of subsequent complications and their healthcare economic impact. The purpose of this study was to quantify the incidence and healthcare resource utilization (HCRU) for major complications that can arise from ICH.

METHODS

The IBM MarketScan Research databases were used to retrospectively identify patients with ICH from 2010 to 2015. Complications examined included cerebral edema, hydrocephalus, venous thromboembolic events (VTEs), pneumonia, urinary tract infections (UTIs), and seizures. For each complication, inpatient mortality and HCRU were assessed.

RESULTS

Of 25,322 adult patients included, 10,619 (42%) developed complications during the initial admission of ICH: 22% had cerebral edema, 11% hydrocephalus, 10% pneumonia, 6% UTIs, 5% seizures, and 5% VTEs. The inpatient mortality rates at 7 and 30 days for each complication of ICH ranked from highest to lowest were hydrocephalus (24% and 32%), cerebral edema (15% and 20%), pneumonia (8% and 18%), seizure (7% and 13%), VTE (4% and 11%), and UTI (4% and 8%). Hydrocephalus had the highest total cost (median $92,776, IQR $39,308-$180,716) at 7 days post-ICH diagnosis and the highest cumulative total cost (median $170,839, IQR $91,462-$330,673) at 1 year post-ICH diagnosis.

CONCLUSIONS

This study characterizes one of the largest cohorts of patients with nontraumatic ICH in the US. More than 42% of the patients with ICH developed complications during initial admission, which resulted in high inpatient mortality and considerable HCRU.

Evaluation of neurapheresis therapy in vitro: a novel approach for the treatment of leptomeningeal metastases

Background

Leptomeningeal metastases (LM), late-stage cancer when malignant cells migrate to the subarachnoid space (SAS), have an extremely poor prognosis. Current treatment regimens fall short in effectively reducing SAS tumor burden. Neurapheresis therapy is a novel approach employing filtration and enhanced circulation of the cerebrospinal fluid (CSF). Here, we examine the in vitro use of neurapheresis therapy as a novel, adjunctive treatment option for LM by filtering cells and augmenting the distribution of drugs that may have the potential to enhance the current clinical approach.

Methods

Clinically relevant concentrations of VX2 carcinoma cells were suspended in artificial CSF. The neurapheresis system’s ability to clear VX2 carcinoma cells was tested with and without the chemotherapeutic presence (methotrexate [MTX]). The VX2 cell concentration following each filtration cycle and the number of cycles required to reach the limit of detection were calculated. The ability of neurapheresis therapy to circulate, distribute, and maintain therapeutic levels of MTX was assessed using a cranial–spinal model of the SAS. The distribution of a 6 mg dose was monitored for 48 h. An MTX-specific ELISA measured drug concentration at ventricular, cervical, and lumbar sites in the model over time.

Results

In vitro filtration of VX2 cancer cells with neurapheresis therapy alone resulted in a 2.3-log reduction in cancer cell concentration in 7.5 h and a 2.4-log reduction in live-cancer cell concentration in 7.5 h when used with MTX. Cranial–spinal model experiments demonstrated the ability of neurapheresis therapy to enhance the circulation of MTX in CSF along the neuraxis.

Conclusion

Neurapheresis has the potential to act as an adjunct therapy for LM patients and significantly improve the standard of care.

Novel Treatment of Cryptococcal Meningitis via Neurapheresis Therapy

Cryptococcal meningitis (CM) has emerged as the most common life-threatening fungal meningitis worldwide. Current management involves a sequential, longitudinal regimen of antifungals; despite a significant improvement in survival compared with uniform mortality without treatment, this drug paradigm has not led to a consistent cure. Neurapheresis therapy, extracorporeal filtration of yeasts from cerebrospinal fluid (CSF) in infected hosts, is presented here as a novel, one-time therapy for CM. In vitro filtration of CSF through this platform yielded a 5-log reduction in concentration of the yeast and a 1-log reduction in its polysaccharide antigen over 24 hours. Additionally, an analogous closed-loop system achieved 97% clearance of yeasts from the subarachnoid space in a rabbit model over 4-6 hours. This is the first publication demonstrating the direct ability to rapidly clear, both in vitro and in vivo, the otherwise slowly removed fungal pathogen that directly contributes to the morbidity and mortality seen in CM.

Novel Dual Lumen Catheter and Filtration Device for Removal of Subarachnoid hemorrhage: First Case Report

BACKGROUND AND IMPORTANCE

The amount of subarachnoid blood and the presence of toxic blood breakdown products in the cerebrospinal fluid (CSF) have long been associated with poor outcomes in aneurysmal subarachnoid hemorrhage. The Neurapheresis™ system (Minnetronix Inc, St. Paul, Minnesota) has been developed to filter CSF and remove blood products, and is being investigated for safety and feasibility in the ExtracorPoreal FILtration of subarachnoid hemorrhage via SpinaL CAtheteR (PILLAR) study. We report the first case using this novel device.

CLINICAL PRESENTATION

A 65-yr-old female presented with a ruptured left posterior communicating artery aneurysm. Following placement of a ventriculostomy and coil embolization of her aneurysm, the patient underwent placement of a lumbar dual lumen catheter for CSF filtration as part of the PILLAR study. In this case, a total of 9 h of filtration during 31 h of catheter indwelling resulted in 309.47 mL of processed CSF without complication. Computed tomography images demonstrated an interval reduction of subarachnoid hemorrhage immediately after filtration. The patient was discharged home on postbleed day 11 and at 30 d showed good recovery.

CONCLUSION

Safety of the Neurapheresis procedure was confirmed in this first case, and we will continue to evaluate safety of the Neurapheresis system through the PILLAR trial.