Abstract 2095: Influence of Patient Profiles on Outcomes With Implantable Mechanical Circulatory Support (MCS): Results from the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS)
Background: For severe, refractory heart failure, implantable MCS is an established therapy when other forms of treatment are ineffective. To refine patient selection to maximize MCS outcomes, a series of 7 patient profiles reflecting acuity and severity of illness were created for the INTERMACS registry. The following analysis was performed to examine the hypothesis that “survival with MCS could be improved by device implantation before the terminal phase of cardiac failure.”
Methods: From 61 centers, 187 pts were entered prospectively into INTERMACS. Pre-implant assignment to an INTERMACS profile was based on level of inotropic support and hemodynamic stability. Ventricular arrhythmias were assigned an additional modifier variable-A.
Results: Of the 187 patients, 78 were assigned to INTERMACS Level 1: Critical cardiogenic shock “crash and burn”; 74 to Level 2: Progressive decline despite inotropes; and 35 assigned to the more stable Levels 3 through 7. Due to varying inotropic support, hemodynamics and renal function did not distinguish between levels 1 through 3. Actuarial survival for patients in INTERMACS Level 1 was 77%±5% and 66%±6% at 1 and 6 months post MCS support and was significantly (P=0.01) less compared to Levels 2 through 7 (91%±3% and 76%±5%, respectively). Addition of the arrhythmia modifier did not impact survival.
Conclusion: Implantation of MCS in the terminal phases of heart failure (INTERMACS 1) is associated with worse outcome than all other profiles. The development of patient profiles beyond measured hemodynamic criteria may help to refine selection and timing for new and future MCS devices.