Increased intraventricular pressures are as harmful as the electrophysiological substrate of heart failure in favoring sustained reentry in the swine heart.

Background: Heart failure (HF) electrophysiological remodeling (HF-ER) often includes the effect of chronically increased intraventricular pressures (IVPs) and promotes ventricular tachycardia/ventricular fibrillation (VT/VF). In addition, acutely increased IVPs have been associated with a higher rate of VT/VF episodes in chronic HF.

Objective: We hypothesized that increased IVPs and/or an ionic-imbalanced (acidified), catecholamine-rich (adrenergic) milieu (AA milieu) may contribute as much as HF-ER to the substrate for reentry in HF.

Morphological and thermodynamic comparison of the lesions created by 4 open-irrigated catheters in 2 experimental models.

Introduction: New generation open-irrigated catheters aim to improve irrigation efficiency. This may change lesion patterns, challenging operators. Indeed, safety issues have recently arisen.

KATP channel opening accelerates and stabilizes rotors in a swine heart model of ventricular fibrillation.

Aims: The mechanisms underlying ventricular fibrillation (VF) are still disputed. Recent studies have highlighted the role of KATP-channels. We hypothesized that, under certain conditions, VF can be driven by stable and epicardially detectable rotors in large hearts.