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Updated: Jun 18, 2025
Post-Myocardial Infarction Heart Failure in Closed-chest Coronary Occlusion/Reperfusion Model in Göttingen Minipigs and Landrace Pigs
Published on: April 17, 2021
The Role of Microvascular Obstruction and Intra-Myocardial Hemorrhage in Reperfusion Cardiac Injury. Analysis of
Vyacheslav V Ryabov1, Evgenii V Vyshlov1, Leonid N Maslov1
1Department of Emergency Cardiology and Laboratory of Experimental Cardiology, Cardiology Research Institute, branch of the Federal State Budgetary Scientific Institution "Tomsk National Research Medical Center of the Russian Academy of Sciences", 634012 Tomsk, Russia.
Abstract:
Microvascular obstruction (MVO) of coronary arteries promotes an increase in mortality and major adverse cardiac events in patients with acute myocardial infarction (AMI) and percutaneous coronary intervention (PCI). Intramyocardial hemorrhage (IMH) is observed in 41-50% of patients with ST-segment elevation myocardial infarction and PCI. The occurrence of IMH is accompanied by inflammation. There is evidence that microthrombi are not involved in the development of MVO. The appearance of MVO is associated with infarct size, the duration of ischemia of the heart, and myocardial edema. However, there is no conclusive evidence that myocardial edema plays an important role in the development of MVO. There is evidence that platelets, inflammation, overload, neuropeptide Y, and endothelin-1 could be involved in the pathogenesis of MVO. The role of endothelial cell damage in MVO formation remains unclear in patients with AMI and PCI. It is unclear whether nitric oxide production is reduced in patients with MVO. Only indirect evidence on the involvement of inflammation in the development of MVO has been obtained. The role of reactive oxygen species (ROS) in the pathogenesis of MVO is not studied. The role of necroptosis and pyroptosis in the pathogenesis of MVO in patients with AMI and PCI is also not studied. The significance of the balance of thromboxane A2, vasopressin, angiotensin II, and prostacyclin in the formation of MVO is currently unknown. Conclusive evidence regarding the role of coronary artery spasm in the development of MVhasn't been established. Correlation analysis of the neuropeptide Y, endothelin-1 levels and the MVO size in patients with AMI and PCI has not previously been performed. It is unclear whether epinephrine aggravates reperfusion necrosis of cardiomyocytes. Dual antiplatelet therapy improves the efficacy of PCI in prevention of MVO. It is unknown whether epinephrine or L-type channel blockers result in the long-term improvement of coronary blood flow in patients with MVO.
Insights
Microvascular obstruction (MVO) after heart attack treatment increases mortality. Key factors like inflammation and platelets are implicated, but many pathways, including oxidative stress and specific signaling molecules, require further investigation for better prevention strategies.
Area of Science:
- Cardiology
- Pathophysiology
- Interventional Cardiology
Background:
- Microvascular obstruction (MVO) is a significant complication following acute myocardial infarction (AMI) treated with percutaneous coronary intervention (PCI), leading to increased mortality and adverse cardiac events.
- Intramyocardial hemorrhage (IMH), often associated with inflammation, occurs in a substantial percentage of STEMI patients undergoing PCI.
- While MVO is linked to infarct size and ischemia duration, the precise underlying mechanisms involving platelets, inflammation, neuropeptide Y, endothelin-1, and other factors remain incompletely understood.
Purpose of the Study:
- To elucidate the complex pathogenesis of microvascular obstruction (MVO) in patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI).
- To investigate the roles of various potential contributors to MVO, including inflammation, platelets, specific signaling molecules, and cellular processes.
- To identify gaps in current knowledge regarding MVO development and to highlight areas for future research.
Main Methods:
- Review of existing evidence on the factors implicated in MVO development, including inflammatory mediators, vasoactive substances, and cellular damage.
- Analysis of associations between MVO and clinical parameters such as infarct size, ischemia duration, and myocardial edema.
- Identification of pathways and molecules with unclear or unstudied roles in MVO pathogenesis, such as reactive oxygen species (ROS), necroptosis, and pyroptosis.
Main Results:
- Microvascular obstruction (MVO) is associated with increased mortality and adverse cardiac events post-PCI for AMI.
- Platelets, inflammation, neuropeptide Y, and endothelin-1 are suggested contributors to MVO, though definitive evidence is lacking for some.
- The roles of endothelial cell damage, nitric oxide production, reactive oxygen species (ROS), necroptosis, pyroptosis, and the balance of specific hormones remain largely uninvestigated.
- Dual antiplatelet therapy shows efficacy in preventing MVO, but long-term effects of certain interventions like epinephrine or calcium channel blockers are unknown.
Conclusions:
- The pathogenesis of microvascular obstruction (MVO) following AMI and PCI is multifactorial and not fully elucidated.
- Further research is crucial to understand the roles of inflammation, oxidative stress, specific signaling pathways, and cell death mechanisms in MVO.
- Clarifying these mechanisms is essential for developing targeted therapies to prevent MVO and improve outcomes for patients with acute myocardial infarction.
