From the Guidelines
An Automated Implantable Cardioverter-Defibrillator (AICD) is needed for cardiomyopathy patients with high-risk features of sudden death, such as those with genetic arrhythmogenic cardiomyopathy and an ejection fraction (EF) ≤45%. According to the most recent guidelines, specifically the 2022 AHA/ACC/HFSA guideline for the management of heart failure 1, AICD implantation is reasonable in patients with genetic arrhythmogenic cardiomyopathy with high-risk features of sudden death and an EF ≤45%.
Key Considerations for AICD Implantation
- High-risk features of sudden death, such as family history of sudden death, unexplained syncope, or documented ventricular arrhythmias
- EF ≤45%
- Genetic arrhythmogenic cardiomyopathy
- Patients who have survived a cardiac arrest or experienced sustained ventricular tachycardia not due to reversible causes, regardless of ejection fraction
Optimal Medical Therapy Before AICD Implantation
Before AICD implantation, patients should be on optimal medical therapy, including:
- Beta-blockers (such as carvedilol, metoprolol)
- ACE inhibitors or ARBs
- Mineralocorticoid receptor antagonists when appropriate
Individualized Decision-Making
The decision for AICD implantation should be individualized, considering the patient's overall prognosis, comorbidities, and preferences. This approach is supported by the 2019 ACC/AHA versus ESC guidelines on heart failure, which emphasize the importance of considering patient-specific factors in device-based therapies for heart failure with reduced ejection fraction (HFrEF) 2.
Prioritizing Morbidity, Mortality, and Quality of Life
In making recommendations for AICD implantation, it is essential to prioritize morbidity, mortality, and quality of life outcomes. The most recent and highest-quality studies, such as the 2022 AHA/ACC/HFSA guideline, should be given precedence in guiding clinical decision-making 1.
From the Research
Indications for AICD in Cardiomyopathy
- An Automated Implantable Cardioverter Defibrillator (AICD) is needed for cardiomyopathy in patients with a left ventricular ejection fraction (LVEF) ≤ 35% 3.
- Patients with hypertrophic cardiomyopathy (HCM) may also benefit from an AICD, especially those at high risk of sudden cardiac death (SCD) 4.
- In patients with idiopathic dilated cardiomyopathy, an AICD may be indicated for primary or secondary prevention of SCD, depending on the patient's risk factors and LVEF 5.
Risk Stratification
- Risk stratification is crucial in determining which patients with cardiomyopathy would benefit from an AICD 4, 6.
- Classical risk factors, such as LVEF and New York Heart Association (NYHA) class, may not be sufficient to identify patients at high risk of SCD 4.
- A new risk prediction model that provides individual 5-year estimated risk may be superior to traditional models based on bivariate risk factors 4.
Medical Treatment Optimization
- Optimization of medical treatment, including the use of β-blockers and angiotensin-converting enzyme inhibitors, may avoid unnecessary AICD implantations in patients with idiopathic dilated cardiomyopathy 7.
- Two thirds of patients with idiopathic dilated cardiomyopathy and "SCD-HeFT criteria" at presentation did not maintain AICD indications 3 to 9 months later with optimal medical therapy 7.
Device Selection and Outcome
- The selection of patients for AICD treatment, device selection, and programming require an individualized approach 6.
- AICDs have evolved from simple defibrillation-only devices to more advanced technologies, including multi-chamber devices and subcutaneous ICDs 6.
- The outcome of AICD implantation depends on various factors, including the patient's underlying condition, LVEF, and NYHA class 3, 5.