Usefulness of Multisite Ventricular Pacing in Nonresponders to Cardiac Resynchronization Therapy.

Cardiac resynchronization therapy (CRT) is an established treatment for heart failure patients with myocardial dysfunction and delayed ventricular activation, but approximately 25% to 40% of patients do not respond to CRT. Left ventricular (LV) multisite pacing (MSP) has been proposed as a tool to improve CRT response. The goal of this study is to examine the safety and efficacy of LV MSP in CRT nonresponders.

Implanted Monitor Alerting to Reduce Treatment Delay in Patients With Acute Coronary Syndrome Events.

Background: Increased pre-hospital delay during acute coronary syndrome (ACS) events contributes to worse outcome.

Objectives: The purpose of this study was to assess the effectiveness of an implanted cardiac monitor with real-time alarms for abnormal ST-segment shifts to reduce pre-hospital delay during ACS events.

Methods: In the ALERTS (AngeLmed Early Recognition and Treatment of STEMI) pivotal study, subjects at high risk for recurrent ACS events (n = 907) were randomized to control (Alarms OFF) or treatment groups for 6 months, after which alarms were activated in all subjects (Alarms ON).

Implantable Cardiac Alert System for Early Recognition of ST-Segment Elevation Myocardial Infarction.

Background: Symptoms remain a poor prompt for acute coronary syndromes (ACS). Timely restoration of perfusion in ST-segment elevation myocardial infarction is associated with improved left ventricular function and survival.

Objectives: This report details the results of ALERTS (AngelMed for Early Recognition and Treatment of STEMI), a multicenter, randomized trial of an implantable cardiac monitor that alerts patients with rapidly progressive ST-segment deviation.

Performance of Anatomically Designed Quadripolar Left Ventricular Leads: Results from the NAVIGATE X4 Clinical Trial.

Introduction: The safety and efficacy of a novel family of quadripolar left ventricular (LV) pacing leads designed to pace from nonapical regions of the LV with low pacing capture thresholds was studied in patients undergoing implantation of a cardiac resynchronization therapy defibrillator (CRT-D).

Methods And Results: Patients receiving a CRT-D were implanted with 1 of 3 ACUITY X4 leads (Spiral Long, Spiral Short, or Straight), designed to address coronary venous anatomical variability. Electrical performance and LV lead related complications were evaluated 3 and 6 months post implantation, respectively.

Image Quality of Cardiac Magnetic Resonance Imaging in Patients With an Implantable Cardioverter Defibrillator System Designed for the Magnetic Resonance Imaging Environment.

Background: Recently, magnetic resonance (MR)-conditional implantable cardioverter defibrillator (ICD) systems have become available. However, associated cardiac MR image (MRI) quality is unknown. The goal was to evaluate the image quality performance of various cardiac MR sequences in a multicenter trial of patients implanted with an MR-conditional ICD system.

Full-Body MRI in Patients With an Implantable Cardioverter-Defibrillator: Primary Results of a Randomized Study.

Background: Magnetic resonance imaging (MRI) of patients with conventional implantable cardioverter-defibrillators (ICD) is contraindicated.

Objectives: This multicenter, randomized trial evaluated safety and efficacy of a novel ICD system specially designed for full-body MRI without restrictions on heart rate or pacing dependency. The primary safety objective was >90% freedom from MRI-related events composite endpoint within 30 days post-MRI.