Uncovering interim clinical events at the time of clinical encounter by reviewing intrathoracic impedance threshold crossings.

Background: Acute decreases in intrathoracic impedance monitored by implanted devices have been shown to precede heart failure exacerbations, although there is still debate regarding its clinical utility in predicting and preventing future events. However, the usefulness of such information to direct patient encounter and enhance patient recall of relevant preceding clinical events at the point of care has not been carefully examined.

Methods And Results: In this multicenter study, we interviewed 326 patients with heart failure who received an implanted device with intrathoracic impedance-monitoring capabilities both before and after device information was reviewed.

Changes in intrathoracic impedance are associated with subsequent risk of hospitalizations for acute decompensated heart failure: clinical utility of implanted device monitoring without a patient alert.

Background: Acute decreases in intrathoracic impedance monitoring have been shown to precede heart failure hospitalization in a limited population of heart failure patients. We evaluated the relationship between changes in intrathoracic impedance with hospitalizations associated with acute decompensated heart failure (ADHF) in patients with cardiac resynchronization therapy plus defibrillator (CRT-D) devices.

Methods And Results: The study enrolled 326 heart failure patients who had received CRT-D with impedance-monitoring capabilities (InSync Sentry, Medtronic).

Ventricular arrhythmia discriminator programming and the impact on the incidence of inappropriate therapy in patients with implantable cardiac defibrillators.

Background: The incidence of inappropriate therapy from implantable cardioverter defibrillators (ICDs) has been reduced by programming ventricular arrhythmia discriminators (VAD) on at the time of implant.

Objective: To determine which VAD is most effective in preventing inappropriate therapy.

Methods And Results: Dual chamber ICD (n=48) or cardiac resynchronization therapy defibrillator (CRT-D) (n=55) implantation was performed in 103 patients (M=94, F=9).

Separating atrial flutter from atrial fibrillation with apparent electrocardiographic organization using dominant and narrow F-wave spectra.

Objectives: The purpose of this study was to separate atrial flutter (AFL) with atypical F waves from fibrillation (AF) with "apparent organization."

Background: We hypothesized that F-wave spectra should reveal a dominant and narrow peak in AFL, reflecting its single macro-re-entrant wave front, but broad spectra in AF, reflecting multiple wave fronts.

Methods: We identified 39 patients with electrocardiograms (ECGs) of "AFL/AF" or "coarse AF" from 134 consecutive patients referred for ablation: 21 had AFL (18 atypical, 3 typical), 18 had AF, and all were successfully ablated.

Sex differences in the causes and natural history of heart failure.

Heart failure is a clinical syndrome of increasing prevalence in the United States, with significant morbidity and mortality. Although men have a higher annual mortality rate, more women than men die from heart failure each year. Optimal disease management is critical in limiting the impact of heart failure on life quality, quantity, and health care expenditures.

Beyond peripheral arteries in Buerger's disease: angiographic considerations in thromboangiitis obliterans.

Thromboangiitis obliterans is an inflammatory peripheral vascular disease that is strongly associated with smoking. It predominantly affects distal small- and medium-sized blood vessels of both the upper and lower extremities. We present histological evidence of this disease process affecting the internal mammary arteries.