Percutaneous cryoablation for papillary muscle ventricular arrhythmias after failed radiofrequency catheter ablation.

Background: Catheter ablation of ventricular arrhythmias (VA) from the papillary muscles (PM) is challenging due to limited catheter stability and contact on the PMs with their anatomic complexity and mobility.

Objective: This study aimed to evaluate the effectiveness of cryoablation as an adjunctive therapy for PM VAs when radiofrequency (RF) ablation has failed.

Methods: We evaluated a retrospective series of patients who underwent cryoablation for PM VAs when RF ablation had failed.

Development of new anatomy reconstruction software to localize cardiac isochrones to the cardiac surface from the 12 lead ECG.

Non-invasive electrocardiographic imaging (ECGI) of the cardiac muscle can help the pre-procedure planning of the ablation of ventricular arrhythmias by reducing the time to localize the origin. Our non-invasive ECGI system, the cardiac isochrone positioning system (CIPS), requires non-intersecting meshes of the heart, lungs and torso. However, software to reconstruct the meshes of the heart, lungs and torso with the capability to check and prevent these intersections is currently lacking.

Sensitivity of CIPS-computed PVC location to measurement errors in ECG electrode position: the need for the 3D camera.

Background: The Cardiac Isochrone Positioning System (CIPS) is a non-invasive method able to localize the origins of PVCs, VT and WPW from the 12 lead ECG. The CIPS model integrates a standard 12-lead ECG with an MRI derived model of the heart, lungs, and torso in order to compute the precise electrical origin of a PVC from within the myocardium. To make these calculations, CIPS uses virtually represented ECG electrode positions.

SIRT2 is a negative regulator of anoxia-reoxygenation tolerance via regulation of 14-3-3 zeta and BAD in H9c2 cells.

Knockdown or inhibition of SIRT2 enhances biological stress-tolerance. We extend this phenotype showing that SIRT2 knockdown reduces anoxia-reoxygenation injury in H9c2 cells. Gene array analysis following SIRT2 siRNA knockdown identifies 14-3-3 zeta as the most robustly induced gene.