page_title: Acute cardiac unloading
section_title: Myocardial infarction
hierarchical_section_title: Acute cardiac unloading / Myocardial infarction
caption_attribution_description: English: Describes increased levels of cardiac unloading and how this uncouples ventricular function from aortic pressure.
context_page_description: Acute cardiac unloading is any maneuver, therapy, or intervention that decreases the power expenditure of the ventricle and limits the hemodynamic forces that lead to ventricular remodeling after insult or injury to the heart. This technique is being investigated as a therapeutic to aid after damage has occurred to the heart, such as after a heart attack. The theory behind this approach is that by simultaneously limiting the oxygen demand and maximizing oxygen delivery to the heart after damage has occurred, the heart is more fully able to recover. This is primarily achieved by using temporary minimally invasive mechanical circulatory support to supplant the pumping of blood by the heart. Using mechanical support decreases the workload of the heart, or unloads it.
  Cardiac traumas such as myocardial infarction, myocarditis, peripartum cardiomyopathy, cardiogenic shock, and takotsubo cardiomyopathy result in an impaired ability of the heart to pump blood. Without proper blood flow the person will ultimately die. Maintaining sufficient cardiac output is the primary objective of therapeutic approaches treating these cardiac conditions.
context_section_description: When the heart is damaged by a myocardial infarction a portion of muscle is permanently lost. The heart has a limited innate ability to replace dead muscle with new, functional muscle. The dead heart muscle is replaced by non-contractile fibrotic tissue, forming the myocardial scar. Scar tissue does not contract, and it does not help the heart pump blood.  This persistently stresses the heart and increases the workload of the lasting myocardium as measured by MVO2. Clinical research indicates that as the size of the myocardial scar increases, so does the likelihood of the patient to develop heart failure.  Acute cardiac unloading decreases cardiac MVO2 and has been demonstrated to limit the amount of scar tissue that forms, thus preserving heart function after a heart attack.
caption: As the level of support increases, aortic pressure is maintained independent of ventricular function. Perfusion pressure is uncoupled from heart function (1-4).[2]
exif: {}