Clinical variability within the INTERMACS 1 profile

Purpose of review The Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) I classification encompasses patients with varying clinical presentations and prognoses. The purpose of this review is to discuss four sub-classifications of cardiogenic shock patients (acute myocardial infarction, acute decompensated heart failure, biventricular failure, and myocarditis), and explore management considerations for these groups, with particular emphasis on strategies for device placement. Recent findings In single-center studies, the use of intra-aortic balloon counterpulsation, percutaneous ventricular assist devices, and extra-corporeal membrane oxygenation (ECMO) has allowed approximately half of cardiogenic shock patients to receive an implantable left ventricular assist device (LVAD) or heart transplant, or experience myocardial recovery. Primary implantation of a durable LVAD in well-selected myocardial infarction shock patients was associated with a 1-year survival of 86% in one small case series. Analysis of a multi-institutional database suggests patients older than 65 years have a lower post-implantation survival compared with younger recipients. Summary Device selection strategies for INTERMACS I patients are predicated on a patient's prognosis, hemodynamic stability, end organ, and neurologic status. Percutaneous assist devices may be preferred for patients with favorable prognoses, ECMO for patients with hemodynamic compromise, and durable mechanical support for patients failing to recover sustainable myocardial function after short-term device use.