Negative Impact of Acute Reloading after Mechanical Left Ventricular Unloading

J Cardiovasc Transl Res. 2024 Apr;17(2):233-241. doi: 10.1007/s12265-023-10371-z. Epub 2023 Apr 6.

Abstract

Mechanical LV unloading for acute myocardial infarction (MI) is a promising supportive therapy to reperfusion. However, no data is available on exit strategy. We evaluated hemodynamic and cellular effects of reloading after Impella-mediated LV unloading in Yorkshire pigs. First, we conducted an acute study in normal heart to observe effects of unloading and reloading independent of MI-induced ischemic effects. We then completed an MI study to investigate optimal exit strategy on one-week infarct size, no-reflow area, and LV function with different reloading speeds. Initial studies showed that acute reloading causes an immediate rise in end-diastolic wall stress followed by a significant increase in cardiomyocyte apoptosis. The MI study did not result in any statistically significant findings; however, numerically smaller average infarct size and no-reflow area in the gradual reloading group prompt further examination of reloading approach as an important clinically relevant consideration.

Keywords: Acute myocardial infarction; Cardiomyocyte apoptosis; Mechanical left ventricle unloading; Reloading; Weaning.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Apoptosis*
  • Disease Models, Animal*
  • Heart-Assist Devices*
  • Hemodynamics
  • Male
  • Myocardial Infarction* / physiopathology
  • Myocardial Infarction* / therapy
  • Myocardium / metabolism
  • Myocardium / pathology
  • Myocytes, Cardiac* / metabolism
  • Myocytes, Cardiac* / pathology
  • No-Reflow Phenomenon / etiology
  • No-Reflow Phenomenon / physiopathology
  • Recovery of Function
  • Sus scrofa*
  • Time Factors
  • Ventricular Function, Left*