Concomitant cryoballoon pulmonary vein and posterior wall isolation in persistent atrial fibrillation: Results from the Left Atrial Posterior Wall Isolation in Conjunction With Pulmonary Vein Isolation Using the Cryoballoon for Treatment of Persistent Atrial Fibrillation (PIVoTAL) IDE trial.

Background: Pulmonary vein isolation (PVI) remains the cornerstone of atrial fibrillation (AF) ablation, but its efficacy in patients with persistent AF (PersAF) remains suboptimal compared with those with paroxysmal AF.

Objective: This study investigated the outcomes of cryoballoon PVI with concomitant "direct" posterior wall isolation (PWI) vs PVI alone in patients with symptomatic PersAF.

Methods: The PIVoTAL IDE was a prospective, multicenter trial (NCT04505163) that randomized patients with symptomatic antiarrhythmic drug-refractory PersAF to cryoballoon PVI vs PVI + PWI.

Outcomes of adjunct posterior wall isolation in atrial fibrillation patients with cardiac implantable electronic devices.

Background: Although pulmonary vein isolation (PVI) remains the cornerstone of catheter ablation of atrial fibrillation (AF), several studies have illustrated clinical benefits associated with PVI with posterior wall isolation (PWI).

Methods: This retrospective study investigated the outcomes of PVI alone versus PVI+PWI performed using the cryoballoon in patients with cardiac implantable electronic devices (CIEDs) and paroxysmal AF (PAF) or persistent AF (PersAF).

Results: Acute PVI was achieved in all patients using cryoballoon ablation.

Pulmonary Vein Isolation With and Without Posterior Wall Isolation in Paroxysmal Atrial Fibrillation: IMPPROVE-PAF Trial.

Background: Prior studies have demonstrated clinical benefits associated with cryoballoon pulmonary vein isolation (PVI) and concomitant posterior wall isolation (PWI) in patients with persistent atrial fibrillation (AF). However, the role for this approach in patients with paroxysmal atrial fibrillation (PAF) remains unclear.

Objectives: This study investigated the acute and long-term outcomes of PVI vs PVI+PWI using cryoballoon in patients with symptomatic PAF.

Acid-induced unfolding of the amino-terminal domains of the lethal and edema factors of anthrax toxin.

The two enzymatic components of anthrax toxin, lethal factor (LF) and edema factor (EF), are transported to the cytosol of mammalian cells by the third component, protective antigen (PA). A heptameric form of PA binds LF and/or EF and, under the acidic conditions encountered in endosomes, generates a membrane-spanning pore that is thought to serve as a passageway for these enzymes to enter the cytosol. The pore contains a 14-stranded transmembrane beta-barrel that is too narrow to accommodate a fully folded protein, necessitating that LF and EF unfold, at least partly, in order to pass.