Unloading the Left Ventricle Before Reperfusion in Patients With Anterior ST-Segment-Elevation Myocardial Infarction

Circulation. 2019 Jan 15;139(3):337-346. doi: 10.1161/CIRCULATIONAHA.118.038269.

Abstract

Background: In ST-segment-elevation myocardial infarction (STEMI), infarct size correlates directly with heart failure and mortality. Preclinical testing has shown that, in comparison with reperfusion alone, mechanically unloading the left ventricle (LV) before reperfusion reduces infarct size and that 30 minutes of unloading activates a cardioprotective program that limits reperfusion injury. The DTU-STEMI pilot trial (Door-To-Unload in STEMI Pilot Trial) represents the first exploratory study testing whether LV unloading and delayed reperfusion in patients with STEMI without cardiogenic shock is safe and feasible.

Methods: In a multicenter, prospective, randomized exploratory safety and feasibility trial, we assigned 50 patients with anterior STEMI to LV unloading by using the Impella CP followed by immediate reperfusion (U-IR) versus delayed reperfusion after 30 minutes of unloading (U-DR). The primary safety outcome was a composite of major adverse cardiovascular and cerebrovascular events at 30 days. Efficacy parameters included the assessment of infarct size by using cardiac magnetic resonance imaging.

Results: All patients completed the U-IR (n=25) or U-DR (n=25) protocols with respective mean door-to-balloon times of 72 versus 97 minutes. Major adverse cardiovascular and cerebrovascular event rates were not statistically different between the U-IR versus U-DR groups (8% versus 12%, respectively, P=0.99). In comparison with the U-IR group, delaying reperfusion in the U-DR group did not affect 30-day mean infarct size measured as a percentage of LV mass (15±12% versus 13±11%, U-IR versus U-DR, P=0.53).

Conclusions: We report that LV unloading using the Impella CP device with a 30-minute delay before reperfusion is feasible within a relatively short time period in anterior STEMI. The DTU-STEMI pilot trial did not identify prohibitive safety signals that would preclude proceeding to a larger pivotal study of LV unloading before reperfusion. An appropriately powered pivotal trial comparing LV unloading before reperfusion to the current standard of care is required.

Clinical trial registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT03000270.

Keywords: heart failure; heart ventricles; heart-assist devices; myocardial infarction; reperfusion injury.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Anterior Wall Myocardial Infarction / diagnostic imaging
  • Anterior Wall Myocardial Infarction / physiopathology
  • Anterior Wall Myocardial Infarction / therapy*
  • Cerebrovascular Disorders / etiology
  • Cerebrovascular Disorders / physiopathology
  • Cerebrovascular Disorders / prevention & control
  • Feasibility Studies
  • Female
  • Heart-Assist Devices*
  • Humans
  • Magnetic Resonance Imaging, Cine
  • Male
  • Middle Aged
  • Myocardial Reperfusion / adverse effects
  • Myocardial Reperfusion / methods*
  • Myocardial Reperfusion Injury / etiology
  • Myocardial Reperfusion Injury / physiopathology
  • Myocardial Reperfusion Injury / prevention & control
  • Pilot Projects
  • Prospective Studies
  • Prosthesis Implantation / adverse effects
  • Prosthesis Implantation / instrumentation*
  • Recovery of Function
  • Recurrence
  • Risk Factors
  • ST Elevation Myocardial Infarction / diagnostic imaging
  • ST Elevation Myocardial Infarction / physiopathology
  • ST Elevation Myocardial Infarction / therapy*
  • Time Factors
  • Treatment Outcome
  • United States
  • Ventricular Function, Left*
  • Young Adult

Associated data

  • ClinicalTrials.gov/NCT03000270