Biventricular ICD Placement Percutaneously Via the Iliac Vein: Case Reports and a Review.

Cardiac resynchronization therapy (CRT) has been demonstrated to improve symptoms of heart failure. As a result, it has become the standard of care in selected patients, and is commonly completed with three leads placed via an upper-extremity vein. However, in rare situations, such as in the case of superior vena cava occlusion, venous access is not possible via the upper extremity.

Assessing the Risks Associated with MRI in Patients with a Pacemaker or Defibrillator.

Background: The presence of a cardiovascular implantable electronic device has long been a contraindication for the performance of magnetic resonance imaging (MRI). We established a prospective registry to determine the risks associated with MRI at a magnetic field strength of 1.5 tesla for patients who had a pacemaker or implantable cardioverter-defibrillator (ICD) that was "non-MRI-conditional" (i.

A novel patch for heart rhythm monitoring: is the Holter monitor obsolete?

A number of substantial improvements to the 60-year-old concept of the Holter monitor have recently been developed. One promising advance is the Zio(®) Patch (iRhythm Technologies, Inc., CA, USA), a small 2 × 5-inch patch, which can continuously record up to 14 days of a single ECG channel of cardiac rhythm without the need for removal during exercise, sleeping or bathing.

Cardiac-resynchronization therapy for the prevention of heart-failure events.

Background: This trial was designed to determine whether cardiac-resynchronization therapy (CRT) with biventricular pacing would reduce the risk of death or heart-failure events in patients with mild cardiac symptoms, a reduced ejection fraction, and a wide QRS complex.

Methods: During a 4.5-year period, we enrolled and followed 1820 patients with ischemic or nonischemic cardiomyopathy, an ejection fraction of 30% or less, a QRS duration of 130 msec or more, and New York Heart Association class I or II symptoms.

Adjudication of mortality events in a heart failure-arrhythmia trial by a multiparameter descriptive method: comparison with methods used in heart failure trials and methods used in arrhythmia trials.

Introduction: Mortality events in studies of cardiovascular disease are currently adjudicated using different methodologies depending on the investigators' preferences. Traditionally, deaths have been categorized by a single term, such as sudden, ischemic, or pump failure, a method that can be referred to as "categorical". In contrast, deaths may be categorized using several specific pieces of information about the event, a method that can be referred to as "multiparameter descriptive.

Inappropriate implantable cardioverter-defibrillator shocks in MADIT II: frequency, mechanisms, predictors, and survival impact.

Objectives: This study sought to identify the incidence and outcome related to inappropriate implantable cardioverter-defibrillator (ICD) shocks, that is, those for nonventricular arrhythmias.

Background: The MADIT (Multicenter Automatic Defibrillator Implantation Trial) II showed that prophylactic ICD implantation improves survival in post-myocardial infarction patients with reduced ejection fraction. Inappropriate ICD shocks are common adverse consequences that may impair quality of life.

Multicenter automatic defibrillator implantation trial-cardiac resynchronization therapy (MADIT-CRT): design and clinical protocol.

The planned MADIT-CRT trial is designed to determine if CRT-D will reduce the risk of mortality and HF events by approximately 25% in subjects with ischemic (NYHA class I-II) and non-ischemic (NYHA class II) cardiomyopathy, left ventricular dysfunction (EFor=130 ms).

Efficacy of lower-energy biphasic shocks for transthoracic defibrillation: a follow-up clinical study.

Objective: This clinical study prospectively evaluated the first-shock defibrillation efficacy of 150-joule impedance-compensated, 200-microF biphasic truncated exponential (BTE) shocks in patients with electrically-induced ventricular fibrillation (VF), and compared it with a historical control group treated with 200-J monophasic damped sine (MDS) shocks.

Methods: Ventricular tachyarrhythmias were induced in patients undergoing electrophysiologic (EP) testing for ventricular arrhythmias or testing of an implantable cardioverter-defibrillator (ICD). A 150-J shock was delivered as the primary therapy to terminate induced arrhythmias in the EP group, and as a "rescue" shock when a single ICD shock failed to terminate the arrhythmias in the ICD group.

Cardiac resynchronization therapy for the treatment of heart failure in patients with intraventricular conduction delay and malignant ventricular tachyarrhythmias.

Objectives: This study was conducted to assess the safety and effectiveness of cardiac resynchronization therapy (CRT) when combined with an implantable cardioverter defibrillator (ICD).

Background: Long-term outcome of CRT was measured in patients with symptomatic heart failure (HF), intraventricular conduction delay, and malignant ventricular tachyarrhythmias (ventricular tachycardia/ventricular fibrillation [VT/VF]) requiring therapy from an ICD.

Methods: Patients (n = 490) were implanted with a device capable of providing both CRT and ICD therapy and randomized to CRT (n = 245) or control (no CRT, n = 245) for up to six months.

Automatic Implantable Cardiac Defibrillators.

Since its first human application in 1980, the automatic implantable cardioverter defibrillator (ICD) has undergone remarkable advances leading to expanded acceptance. Originally indicated only for patients who had survived two cardiac arrests, the devices have recently been shown to improve survival in all patients with prior myocardial infarction and an ejection fraction of 30% or less. The devices have been miniaturized and are now implanted transvenously, often with hospital discharge within 24 hours of surgery.

Prophylactic implantation of a defibrillator in patients with myocardial infarction and reduced ejection fraction.

Background: Patients with reduced left ventricular function after myocardial infarction are at risk for life-threatening ventricular arrhythmias. This randomized trial was designed to evaluate the effect of an implantable defibrillator on survival in such patients.

Methods: Over the course of four years, we enrolled 1232 patients with a prior myocardial infarction and a left ventricular ejection fraction of 0.

The Low Energy Safety Study (LESS): rationale, design, patient characteristics, and device utilization.

Background: A 10-J energy safety margin has traditionally been used in programming implantable cardioverter defibrillators (ICDs). The Low Energy Safety Study (LESS) tests the hypothesis that programming shocks to lower energy margins is safe and effective.

Methods: Patients with standard ICD indications undergo defibrillation threshold testing (DFT) at the time of ICD implant, with reconfirmation of lowest successful energy twice (DFT++).