Related Experiment Video
Updated: May 8, 2026
Chronic Thromboembolic Pulmonary Hypertension and Assessment of Right Ventricular Function in the Piglet
Published on: November 4, 2015
Microvascular obstruction in the right ventricle in reperfused anterior myocardial infarction. Macroscopic and
Clara Bonanad1, Amparo Ruiz-Sauri, Maria J Forteza
1Department of Cardiology, Hospital Clinico Universitario, INCLIVA, University of Valencia, Spain.
Introduction:
Data on right ventricular (RV) involvement in anterior myocardial infarction are scarce. The presence of RV microvascular obstruction (MVO) in this context has not been analyzed yet. The aim of the present study was to characterize the presence of MVO in the RV in a controlled experimental swine model of reperfused anterior myocardial infarction.
Materials And Methods:
Left anterior descending (LAD) artery-perfused area (thioflavin-S staining after selective infusion in LAD artery), infarct size (lack of triphenyltetrazolium-chloride staining) and MVO (lack of thioflavin-S staining in the core of the infarcted area) in the RV were studied. A quantitative (% of the ventricular volume) and semiquantitative (number of segments involved) analysis was carried out both in the RV and LV in a 90-min left anterior descending balloon occlusion and 3-day reperfusion model in swine (n=15).
Results:
RV infarction and RV MVO (>1 segment) were detected in 9 (60%) and 6 (40%) cases respectively. Mean LAD-perfused area, infarct size and MVO in the RV were 33.8 ± 13%, 13.53 ± 11.7% and 3.4 ± 4.5%. Haematoxylin and eosin stains and electron microscopy of the RV-MVO areas demonstrated generalized cardiomyocyte necrosis and inflammatory infiltration along with patched hemorrhagic areas. Ex-vivo nuclear magnetic resonance (T2 sequences) microimaging of RV-MVO showed, in comparison with remote non-infarcted territories, marked hypointense zones (corresponding to necrosis, inflammation and hemorrhage) in the core of hyperintense regions (corresponding to edema).
Conclusions:
In reperfused anterior myocardial infarction, MVO is frequently present in the RV. It is associated with severe histologic repercussion on the RV wall. Nuclear magnetic resonance appears as a promising technique for the noninvasive detection of this phenomenon. Further studies are warranted to evaluate the pathophysiological and clinical implications.
Insights
Microvascular obstruction (MVO) frequently affects the right ventricle (RV) in anterior myocardial infarction, causing severe RV wall damage. Nuclear magnetic resonance shows promise for noninvasive detection of this condition.
Area of Science:
- Cardiovascular Research
- Myocardial Infarction Pathophysiology
- Experimental Cardiology
Background:
- Limited data exists on right ventricular (RV) involvement in anterior myocardial infarction.
- The presence and characteristics of RV microvascular obstruction (MVO) in this context remain unanalyzed.
Purpose of the Study:
- To investigate the occurrence and extent of RV microvascular obstruction (MVO) in a swine model of reperfused anterior myocardial infarction.
- To characterize the histological and imaging features of RV MVO.
Main Methods:
- A swine model with 90-minute LAD occlusion and 3-day reperfusion was used (n=15).
- RV infarct size, LAD-perfused area, and MVO were quantified using histological staining (thioflavin-S, triphenyltetrazolium-chloride).
- RV MVO was further assessed using ex-vivo nuclear magnetic resonance (T2 sequences).
Main Results:
- RV infarction occurred in 60% and RV MVO in 40% of cases.
- Histology revealed cardiomyocyte necrosis, inflammation, and hemorrhage in RV MVO areas.
- Nuclear magnetic resonance demonstrated hypointense zones in RV MVO, correlating with necrosis, inflammation, and hemorrhage.
Conclusions:
- Microvascular obstruction (MVO) is a frequent finding in the right ventricle (RV) following reperfused anterior myocardial infarction.
- RV MVO is associated with significant histological damage to the RV wall.
- Nuclear magnetic resonance is a promising noninvasive technique for detecting RV MVO, warranting further clinical investigation.
