Identifying high-risk post-infarction patients by autonomic testing - Below the tip of the iceberg.
Despite major advances in medical therapies late mortality after myocardial infarction (MI) is still high. A substantial proportion of post-MI patients die from sudden cardiac death. Prophylactic implantable-cardioverter defibrillator (ICD) therapy has been established for post-MI patients with reduced left ventricular ejection fraction (LVEF ≤35%). However, most patients who die after MI have an LVEF >35%. For this large group of patients, no specific prophylactic strategies exist. There is strong evidence that measures of cardiac autonomic dysfunction after MI provide important prognostic information in post-MI patients with preserved LVEF. Combinations of autonomic markers can identify high-risk patients after MI with LVEF >35% whose prognosis is equally worse than that of patients with LVEF ≤35%. The ongoing REFINE-ICD (NCT00673842) and SMART-MI trials (NCT02594488) test different preventive strategies in high-risk post-MI patients with cardiac autonomic dysfunction and LVEF 36-50%. While REFINE-ICD follows the traditional concept of ICD-implantation, SMART-MI uses implantable cardiac monitors with remote monitoring capabilities to sensitively detect asymptomatic, but prognostically relevant arrhythmias that could trigger specific diagnostic and therapeutic interventions.
Medizinische Klinik und Poliklinik I, Munich University Clinic, Munich, Germany; German Center for Cardiovascular Research (DZHK), Germany. Electronic address: axel.bauer@med.uni-muenchen.de.
Axel
A
Bauer
D001342:Autonomic Nervous System Diseases / Q000175:diagnosis* / Q000503:physiopathology* / Q000628:therapy; D017147:Defibrillators, Implantable / Q000639:trends; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000503:physiopathology* / Q000628:therapy; D016032:Randomized Controlled Trials as Topic / Q000379:methods; D012307:Risk Factors
Cardiac autonomic function; ECG; Heart rate variability; Implantable defibrillator myocardial infarction; Sudden cardiac death