Why ICDs are less effective in Non Ischemic DCM ?

We wish, our understanding about cardiac contractile physiology is deep and nearly complete. Heart is an irreversibly coupled electro-mechanical organ , right from the fetal days until the final heart beat. In myocardial pathology, the genesis and sustainability of ventricular arrhythmia are intricately related to the degree of LV dysfunction of any cause. SCD is the leading cause of mortality in heart failure. Tackling SCD was in God’s domain, until the brilliance of Dr. Michel Mirowski shrunk the defibrillator and implanted it under the chest in 1980. (Dr. MM’s s a unique and inspiring story, from Poland amidst the holocaust times, right up to his invention at Johns Hopkins) Why ICD for SCD ? Beta blockers and Amiodarone remain good options for mitigating SCD. (Of course, Amiodarone has a huge baggage of side effects.) But, as you know machines always beat drugs. After multiple RCTs, we found any severe LV dysfunction (EF <30%) requires an ICD to reduce SCD. Though MADIT trial required an inducibility of VT, MADIT-2 told us that just the presence of LV dysfunction is sufficient. Since then, ICDs have proliferated globally, of course with multiple collateral issues. As we navigated the cardiac EP terrain further, we found that all is not well. ICDs faced some foundational questions regarding its utility value vs. risk . ICD explanation epidemic in the past was a true story. Still, Mirowski”s electrical kid survived the test of time and evo...
Source: Dr.S.Venkatesan MD - Category: Cardiology Authors: Tags: Uncategorized crt device crt-p vs crt-d danish trial ischemic dcm madit trial non ischemic dcm Source Type: blogs