When would a patient with atrial fibrillation (afib) require implantable cardioverter-defibrillator (ICD) placement?

From the Guidelines

A patient with atrial fibrillation (AFib) requires implantable cardioverter-defibrillator (ICD) placement if they have additional high-risk cardiac conditions, such as heart failure with reduced ejection fraction (LVEF ≤35%) or genetic arrhythmogenic cardiomyopathy with high-risk features of sudden death. When considering ICD placement for AFib patients, it's crucial to assess their overall cardiac risk profile, including the presence of heart failure, reduced ejection fraction, and history of ventricular arrhythmias. According to the 2022 AHA/ACC/HFSA guideline for the management of heart failure 1, ICD implantation is reasonable in patients with genetic arrhythmogenic cardiomyopathy with high-risk features of sudden death and an ejection fraction (EF) ≤45%. Key considerations for ICD placement in AFib patients include:

• Presence of heart failure with reduced ejection fraction (LVEF ≤35%) despite optimal medical therapy
• History of sudden cardiac arrest or sustained ventricular tachycardia
• Certain genetic heart conditions like hypertrophic cardiomyopathy or arrhythmogenic cardiomyopathy
• Anticipated requirement for significant ventricular pacing The primary goal of ICD placement in these high-risk patients is to reduce the risk of sudden cardiac death by automatically detecting and treating life-threatening ventricular arrhythmias. In contrast, standard AFib management focuses on rate control, rhythm control, and stroke prevention, rather than ICD therapy, unless the patient has one of the aforementioned high-risk conditions.

From the Research

Implantable Cardioverter-Defibrillator (ICD) Placement in Atrial Fibrillation (AFib)

• ICD placement is typically recommended for primary prevention of sudden cardiac death (SCD) in patients with heart failure with reduced ejection fraction (HFrEF) [(2,3,4,5,6)].
• The decision to implant an ICD in patients with AFib should be based on individual risk assessment, taking into account factors such as left ventricular ejection fraction, symptoms, and comorbidities [(4,5,6)].
• Current guidelines recommend ICD implantation for primary prevention in patients with HFrEF and a left ventricular ejection fraction ≤35% after at least 3 months of optimized heart failure treatment [(2,3)].

Predictors of ICD Use

• Predictors of ICD use include higher predicted proportional sudden cardiac death risk, follow-up in specialty care, lower comorbidity burden, and higher socioeconomic status 6.
• Barriers to ICD use include lack of specialized follow-up, higher comorbidity burden, and lower socioeconomic status 6.

Mortality Risk and ICD Use

• ICD use is associated with reduced short- and long-term all-cause mortality in patients with HFrEF 5.
• The association between ICD use and reduced mortality is consistent across all investigated subgroups, including patients with versus without ischemic heart disease, men versus women, and those aged <75 versus ≥75 years 5.
• ICD use is associated with lower mortality only in patients with higher predicted sudden cardiac death and lower mortality risk 6.