ICD Therapy

ICDs in the Post-ACS Period

DINAMIT: Prophylactic implantation of an ICD 6-40 days after acute MI in patients with LV dysfunction (LVEF ≤ 35%) and impaired autonomic function reduces arrhythmic deaths but does not improve all-cause mortality.
1. Increased non-arrhythmic death
IRIS: Prophylactic ICD therapy did not reduce overall mortality in patients with AMI and clinical features that increased risk of death/SCD (LVEF < 40%, HR > 90 or nonsustained VT on Holter). Timeframe was 5-31 days.
1. Decreased SCD
2. Increased nonsudden cardiac death
CABG-Patch showed no survival benefit with early ICD implantation in high-risk patients who underwent bypass surgery with a low LVEF, presumably because of an altered risk of SCD with revascularization

ICDs are generally only recommended for patients with ischemic/non-ischemic CM at least 40 days post-MI with reduced EF < 35% and NYHA class II-III symptoms on Guideline-Directed Medical Therapy with expected survival > 1 year. (IA recommendation)
ICDs are recommended for patients with ischemic CM at least 40 days post-MI with reduced EF < 30% and NYHA class I symptoms on GDMT with expected survival > 1 year. (IB recommendation)

ICDs are indicated if:

Cardiac arrest due to ventricular arrhythmia in the absence of reversible cause
Sustained VT/VF in the absence of reversible causes (at least 48 hours post-MI or revascularization)
Syncope in the presence of structural heart disease, where the underlying cause is thought to be sustained VT/VF and the risk of recurrence is high or proven to be reproducible on EP studies