High-precision, mass dependent Si isotope measurements the critical mixture double-spiking technique.

We have developed a new method for measuring mass dependent Si isotope fractionation critical mixture double-spiking. Samples need to be spiked before column chemistry to guarantee full equilibrium between the sample and double-spike (Si-Si spike). An iterative addition of the double-spike to the sample, usually 2-4 times, is needed to generate a solution very close to the critically spiked mixture.

High-density mapping for ablation of atypical atrial flutters - procedural characteristics related to outcome.

Background: High-density (HD) mapping is increasingly used to characterize arrhythmic substrate for ablation of atypical atrial flutters (AAFl). However, results on clinical outcomes and factors that are associated with arrhythmia recurrence are scarce.

Methods: Single-center, prospective, observational cohort study that enrolled patients with catheter ablation for AAFl using a HD mapping system and a grid-shaped mapping catheter.

Ultra-Low Temperature Cryoablation for Atrial Fibrillation: Primary Outcomes for Efficacy and Safety: The Cryocure-2 Study.

Ultra-low temperature cryoablation (ULTC) is a novel ablation modality aiming to combine the effectiveness of surgical lesion delivery with percutaneous safety to improve outcomes in catheter ablations of atrial fibrillation, particularly in persistent AF (PsAF). In the Cryocure-2 study (NCT02839304) 78 patients (56.4% PsAF) received ULTC pulmonary vein isolation plus posterior wall ablation, and linear left and right atrial lesions as needed.

Extracellular matrix remodeling precedes atrial fibrillation: Results of the PREDICT-AF trial.

Background: To which extent atrial remodeling occurs before atrial fibrillation (AF) is unknown.

Objective: The PREventive left atrial appenDage resection for the predICtion of fuTure Atrial Fibrillation (PREDICT-AF) study investigated such subclinical remodeling, which may be used for risk stratification and AF prevention.

Methods: Patients (N = 150) without a history of AF with a CHADS-VASc score of ≥2 at an increased risk of developing AF were included.

Efficacy and safety of the GOLD FORCE multicentre randomized clinical trial: multielectrode phased radiofrequency vs. irrigated radiofrequency single-tip catheter with contact force ablation for treatment of symptomatic paroxysmal atrial fibrillation.

Aims: Pulmonary vein isolation (PVI) for atrial fibrillation (AF) has become increasingly safe and effective with the evolution of single-tip ablation catheters aided by contact force sensing (ST-CF) and single-shot devices such as the second-generation pulmonary vein ablation catheter (PVAC) Gold multi-electrode array. The multicentre randomized GOLD FORCE trial was conducted to evaluate non-inferiority of safety and efficacy of PVAC Gold PVI compared to ST-CF ablation for paroxysmal AF.

Methods And Results: The primary efficacy endpoint documented AF recurrence ≥30 s was assessed by time-to-first-event analysis after a 90-day blanking period using repeated 7-day Holters.

Ultralow temperature cryoablation using near-critical nitrogen for cavotricuspid isthmus-ablation, first-in-human results.

Introduction: Cryoablation has evolved as a safe alternative to radiofrequency ablation in the treatment of several supraventricular arrhythmias and has potential advantages, yet is limited by the properties of the cryogen used. We investigated a novel ultralow temperature cryoablation (ULTC) system using nitrogen near its liquid-vapor critical point as a freezing source, achieving temperatures as low as -196 degrees Celsius in a long linear catheter with a continuous energy release. Initial safety, procedural and efficacy outcomes of ULTC are described in patients undergoing cavotricuspid isthmus (CTI) ablation.

Paroxysmal and persistent atrial fibrillation ablation outcomes with the pulmonary vein ablation catheter GOLD duty-cycled phased radiofrequency ablation catheter: quality of life and 12-month efficacy results from the GOLD Atrial Fibrillation Registry.

Aims: The GOLD AF Registry has been designed to prospectively assess the population, indications, and outcomes using second-generation phased radiofrequency (RF) ablation (pulmonary vein ablation catheter GOLD) in a global examination of standard-of-care use for the treatment of paroxysmal and persistent atrial fibrillation (AF).

Methods And Results: GOLD AF (NCT02433613) is a prospective, observational, multi-centre registry designed to characterize efficacy and safety of phased RF ablation in patients with AF. The primary endpoint was freedom from AF recurrence at 12-month follow-up after a 90-day blanking period.

Left atrial catheter ablation in patients with previously implanted left atrial appendage closure devices.

Aims: Left atrial appendage closure (LAAC) is increasingly used as an alternative to oral anticoagulation (OAC) for stroke prevention in atrial fibrillation (AF) patients. Feasibility and safety of left atrial (LA) catheter ablation (CA) in patients with previously implanted LAAC devices have not been well studied. We report on the feasibility, safety, and efficacy of LA CA in the presence of a previously implanted LAAC device.

[Percutaneous left atrial appendage closure for stroke prevention in atrial fibrillation: is left atrial appendage closure an alternative for anticoagulation?].

The left atrial appendage (LAA) is the main source of cardioembolic stroke in patients with atrial fibrillation without valvular disease. Oral anticoagulation (OAC) has proven effective for preventing strokes associated with atrial fibrillation but is complicated by inherent bleeding risk and therapeutic compliance. Mechanical closure of the left atrial appendage seems an attractive alternative, especially in patients for whom long-term oral anticoagulation is not a good option.

A distinct source and differentiation history for Kolumbo submarine volcano, Santorini volcanic field, Aegean arc.

This study reports the first detailed geochemical characterization of Kolumbo submarine volcano in order to investigate the role of source heterogeneity in controlling geochemical variability within the Santorini volcanic field in the central Aegean arc. Kolumbo, situated 15 km to the northeast of Santorini, last erupted in 1650 AD and is thus closely associated with the Santorini volcanic system in space and time. Samples taken by remotely-operated vehicle that were analyzed for major element, trace element and Sr-Nd-Hf-Pb isotope composition include the 1650 AD and underlying K2 rhyolitic, enclave-bearing pumices that are nearly identical in composition (73 wt.