Related Experiment Video
Updated: Aug 7, 2026
12:45
Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
DEFibrillators In Non-Ischemic Cardiomyopathy Treatment Evaluation (DEFINITE)
Andi Schaechter1, Alan H Kadish,
1Division of Cardiology, Department of Medicine, Northwestern University Medical School, Chicago, IL, USA.
Cardiac Electrophysiology Review
|April 9, 2004
Summary
The DEFINITE trial evaluated implantable cardioverter defibrillators (ICDs) for non-ischemic cardiomyopathy. ICDs are expected to significantly reduce mortality in high-risk heart failure patients.
Area of Science:
- Cardiology
- Clinical Trials
- Medical Devices
Background:
- Non-ischemic cardiomyopathy (NICM) with reduced ejection fraction (
- Standard medical therapy for heart failure may not sufficiently mitigate sudden cardiac death risk in these patients.
Purpose of the Study:
- To evaluate the efficacy of implantable cardioverter defibrillators (ICDs) in reducing total mortality in patients with NICM.
- To assess the impact of ICDs on quality of life and healthcare costs in this population.
Main Methods:
- The DEFibrillators In Non-Ischemic Cardiomyopathy Treatment Evaluation (DEFINITE) trial was a multi-center, randomized study.
- Patients with NICM, symptomatic heart failure, and documented arrhythmias were randomized to ICD or no ICD, alongside standard medical therapy.
- Follow-up was for 2-3 years, with total mortality as the primary endpoint.
Main Results:
- An estimated annual mortality of 15% at 2 years was projected for the no-ICD arm.
- ICDs were anticipated to reduce mortality by 50% in the target population.
- The study required approximately 229 patients per group for adequate statistical power.
Conclusions:
- ICDs represent a potential life-saving intervention for select patients with non-ischemic cardiomyopathy and high-risk arrhythmias.
- Further analysis of quality of life and pharmacoeconomics is crucial for comprehensive treatment evaluation.
Related Concept Videos
01:26Heart Failure Drugs: Inotropic Agents
Positive inotropic agents are commonly used as the first line of treatment for heart failure. One such agent is digoxin, derived from the genus Digitalis, which has been known for centuries but effectively utilized since 1785. However, these cardiac glycosides can have potentially toxic effects due to their mechanism of action, which involves inhibiting Na+/K+-ATPase and increasing contractility. Digoxin is absorbed orally and distributed in various tissues, including the CNS. It has a long...
01:25Dysrhythmias VI: Management of Dysrhythmias
Dysrhythmia management involves a multifaceted approach, incorporating pharmacological treatments, medical procedures, surgical interventions, lifestyle modifications, and patient education.Pharmacological ManagementAntiarrhythmic Drugs:Class I (Sodium Channel Blockers): This class includes quinidine and procainamide, which reduce the speed of impulse conduction in the heart, stabilize the cardiac membrane, and control arrhythmias. Quinidine and procainamide are Class IA agents that prolong the...
01:30Cardiomyopathy II: Dilated Cardiomyopathy
Dilated cardiomyopathy, or DCM, is a progressive myocardial disorder characterized by ventricular chamber dilation and contractile dysfunction.EtiologyVarious factors can cause DCM, including hypertension and heavy alcohol intake, which contribute to the weakening and enlargement of the heart muscle. Viral infections, such as Coxsackievirus B, adenoviruses, and influenza, can lead to DCM by causing inflammation and damage to heart tissue. Certain chemotherapeutic agents, including daunorubicin,...
01:29Cardiomyopathy III: Hypertrophic Cardiomyopathy
Hypertrophic cardiomyopathy, or HCM, is an autosomal dominant genetic disorder characterized by asymmetric left ventricular hypertrophy without ventricular dilation. It is more common in men and is typically diagnosed in young, athletic adults.EtiologyHCM is primarily genetic and is caused by mutations in genes encoding sarcomeric proteins. Researchers have identified over 1400 mutations across at least 11 different genes. Among these, the most frequently occurring mutations are found in the...
01:29Cardiomyopathy V: Interprofessional Care
Managing cardiomyopathy involves addressing underlying or precipitating causes, treating heart failure with medications, and implementing dietary changes and a balanced exercise and rest regimen.Lifestyle ModificationsCardiomyopathy patients should adopt a low-sodium diet to reduce fluid retention and manage heart failure. A personalized exercise and rest plan helps maintain physical fitness without overstraining the heart. Avoiding alcohol and tobacco is essential to prevent further damage to...
01:25ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias
Arrhythmia is a condition characterized by an irregular heart rhythm, with ECG changes that differ based on its origin and nature. The types of arrhythmias discussed below include atrial, junctional, and ventricular arrhythmias.Atrial ArrhythmiasPremature Atrial Complexes (PACs): PACs are early atrial beats caused by stress, caffeine, alcohol, electrolyte imbalances, hypoxia, hyperthyroidism, or certain medications (e.g., bronchodilators and decongestants). The ECG shows early P waves with an...