From the Guidelines
Implantable Cardioverter-Defibrillator (ICD) placement is recommended for patients with NYHA class II or III heart failure who have a left ventricular ejection fraction (LVEF) of 35% or less, or 31-35% with NYHA class II or III, despite receiving optimal medical therapy for at least three months, as indicated in the 2025 ACC/AHA/ACEP/NAEMSP/SCAI guideline 1.
Key Considerations for ICD Placement
- Patients should be on guideline-directed medical therapy including beta-blockers, ACE inhibitors or ARBs, mineralocorticoid receptor antagonists, and potentially SGLT2 inhibitors before ICD placement is considered.
- The patient should have a reasonable expectation of survival with good functional status for more than one year.
- For ischemic cardiomyopathy patients, ICD placement should be at least 40 days post-myocardial infarction and 90 days post-revascularization.
- Non-ischemic cardiomyopathy patients should demonstrate persistent reduced ejection fraction despite optimal medical therapy.
- Cardiac resynchronization therapy with defibrillator (CRT-D) should be considered for patients with NYHA class II-III, LVEF ≤35%, and a QRS duration ≥130 ms, particularly with left bundle branch block, as supported by the 2015 ESC guidelines 1.
Rationale for ICD Placement
- ICDs are effective because they can detect life-threatening arrhythmias and deliver appropriate therapy to terminate ventricular tachycardia or fibrillation, which are common causes of sudden cardiac death in heart failure patients with reduced ejection fraction.
- The benefit of ICD placement in reducing sudden cardiac death has been demonstrated in several studies, including the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT) 1.
Additional Considerations
- ICD therapy is also recommended in patients with documented ventricular fibrillation or hemodynamically unstable VT in the absence of reversible causes, or within 48 hours of MI, as stated in the 2020 ESC guidelines on diabetes, pre-diabetes, and cardiovascular diseases 1.
- Beta-blockers are recommended for patients with heart failure and after acute MI with LVEF <40%, to prevent sudden cardiac death.
From the Research
Criteria for ICD Placement in NYHA Class II or III Heart Failure
The criteria for Implantable Cardioverter-Defibrillator (ICD) placement in patients with New York Heart Association (NYHA) class II or III heart failure are based on several studies, including 2, 3, 4, 5, 6.
- Left Ventricular Ejection Fraction (LVEF): Patients with an LVEF of 35% or less are considered eligible for ICD placement, as shown in studies 2, 3, 4.
- NYHA Class: Patients with NYHA class II or III symptoms are considered eligible for ICD placement, as shown in studies 2, 3, 4.
- Optimal Medical Therapy: Patients should be on optimal medical therapy, including diuretics, angiotensin-converting enzyme (ACE) inhibitors, beta blockers, and angiotensin II receptor blockers, as recommended in study 3.
- Expectation of Survival: Patients should have an expectation of survival of at least 1 year, as recommended in study 3.
- Ischemic or Nonischemic Cardiomyopathy: Patients with ischemic or nonischemic cardiomyopathy are considered eligible for ICD placement, as shown in studies 2, 3, 4.
- History of Cardiac Arrest or Ventricular Tachycardia: Patients with a history of cardiac arrest, ventricular fibrillation, or hemodynamically unstable ventricular tachycardia are considered eligible for ICD placement, as recommended in study 3.
Additional Considerations
- Cardiac Resynchronization Therapy: Patients with an LVEF of 35% or less, NYHA class III or IV symptoms, and a QRS duration greater than 120 ms may be considered for cardiac resynchronization therapy, as recommended in study 3.
- Aldosterone Antagonists: Patients with moderate to severe heart failure symptoms and reduced LVEF may be considered for aldosterone antagonists, as recommended in study 5.
- Monitoring: Patients with ICDs should be closely monitored for device therapy and mortality, as shown in study 6.