The use of Impella 2.5 in severe refractory cardiogenic shock complicating an acute myocardial infarction.

Objectives: To investigate the outcome of patients with acute myocardial infarction (AMI) complicated by refractory cardiogenic shock (CS) who underwent mechanical circulatory support with Impella 2.5.

Background: AMI complicated by CS remains a highly fatal condition. A potent and minimally invasive left ventricular assist device might improve patient outcomes.

Methods: We analyzed the procedural characteristics and outcomes of 22 consecutive patients who underwent, between July 2008 and December 2012, a percutaneous coronary intervention and Impella 2.5 support for AMI complicated by CS refractory to first-line therapy with inotropes and/or Intra-aortic balloon pump.

Results: In this analysis, patients were relatively young with a mean age of 57.9 ± 11.6 year old and 59.1% were male. The majority of patients (77.3%) were admitted in CS and 40.9% sustained cardiac arrest prior to admission. Hemodynamics improved significantly upon initiation of support, end-organ and tissue perfusion improved subsequently demonstrated by a significant decrease in lactate levels from 6.37 ± 5.3 mmol/L to 2.41 ± 2.1 mmo/L, (P =  0.008) after 2 days of support. Thirteen (59.1%) patients were successfully weaned-off Impella 2.5 and 4 (18.2%) were transitioned to another device. We observed a functional recovery of the left ventricle when compared to baseline (43 ± 10% vs. 27 ± 9%, P < 0.0001). The survival rate at 6 months and 1 year was 59.1% and 54.5%, respectively.

Conclusion: Impella 2.5 was initiated as a last resort therapy to support very sick patients with refractory CS after failed conventional therapy. The use of the device yielded favorable short and mid-term survival results with recovery being the most frequently observed outcome.