A multicenter study of shock pathways for subcutaneous implantable defibrillators.

Introduction: A purely subcutaneous implantable cardioverter defibrillator (ICD) requires higher energy but may be an effective alternative to transvenous ICDs to deliver lifesaving therapies.

Objective: To identify combinations of anteroposterior subcutaneous shock pathways and waveforms with defibrillation efficacy comparable to transvenous ICDs.

Methods: Defibrillation testing was performed in 141 patients temporarily implanted with an active can emulator and subcutaneous coil electrodes.

Performance of Lead Integrity Alert to assist in the clinical diagnosis of implantable cardioverter defibrillator lead failures: analysis of different implantable cardioverter defibrillator leads.

Background: The Lead Integrity Alert (LIA) was developed for Medtronic implantable cardioverter defibrillators to reduce inappropriate shocks for rapid oversensing caused by conductor fractures and reported for Medtronic Fidelis conductor fractures. The goal of this study was to compare the performance of LIA with conventional impedance monitoring for identifying lead system events (LSEs) and lead failures (LFs) in lead families that differ from Fidelis.

Methods And Results: We analyzed data from 12 793 LIA enabled implantable cardioverter-defibrillator and lead combinations including 6123 St.

Influence of intracardiac pressure on spontaneous ventricular arrhythmias in patients with systolic heart failure: insights from the REDUCEhf trial.

Background: The implantation of a combination hemodynamic monitor-cardioverter-defibrillator in the Reducing Decompensation Events Utilizing Intracardiac Pressures in Patients with Chronic Heart Failure (REDUCEhf) study allowed assessment of the relationship between daily intracardiac pressure and occurrence of ventricular arrhythmic (VT/VF) events.

Methods And Results: Median estimated pulmonary artery diastolic pressures (ePAD) were calculated every 24 hours in 378 subjects with New York Heart Association functional class II-III heart failure who had at least 60 days of hemodynamic data. Forty-six subjects experienced 140 VT/VF events on 80 unique study days in which daily median ePAD was available.

Alcoholism treatment episodes validly defined using mental health care utilization records.

Objective: We propose a method for defining and empirically validating episodes of alcoholism treatment from health care utilization records.

Study Design And Setting: The study includes utilization records from 86,207 patients enrolled in a large managed behavioral care company who had at least one alcoholism encounter between 1991 and 1998. Treatment episodes are defined as a minimum number of alcoholism treatment encounters with the behavioral care company prior to a "clear zone" of no encounters.