Endothelial progenitor cells, microvascular obstruction, and left ventricular remodeling in patients with ST
Italo Porto1, Giovanni Luigi De Maria, Antonio Maria Leone
1Department of Cardiovascular Medicine, San Donato Hospital, Arezzo, Italy. italo.porto@gmail.com
Insights
Mobilization of endothelial progenitor cells (EPCs) during myocardial infarction correlates with infarct size and microvascular obstruction. Persistently low EPC levels predict adverse left ventricular remodeling after ST-elevation myocardial infarction.
Area of Science:
- Cardiovascular Medicine
- Regenerative Medicine
- Cell Biology
Background:
- Endothelial progenitor cells (EPCs) are crucial for vascular repair.
- EPC mobilization from bone marrow is observed during cardiac ischemic events.
- The role of EPCs in ST-elevation myocardial infarction (STEMI) and subsequent left ventricular (LV) remodeling requires further investigation.
Purpose of the Study:
- To assess clinical and angiographic correlates of EPC mobilization during primary percutaneous coronary intervention in STEMI patients.
- To evaluate the impact of baseline and follow-up EPC levels on LV remodeling.
- To understand the relationship between EPC levels and infarct characteristics.
Main Methods:
- Cytofluorimetric detection of EPCs (CD34+CD45dimKDR+ cells) in aortic and intracoronary blood during primary PCI.
- Assessment of area at risk, thrombus burden, and microvascular obstruction (MVO).
- Echocardiographic evaluation of LV remodeling at 1-year follow-up; reassessment of peripheral EPC levels.
Main Results:
- Intracoronary EPC levels were significantly higher than aortic levels during STEMI.
- Both intracoronary and aortic EPC levels correlated with infarct size, thrombus burden, and inversely with MVO.
- Lower peripheral EPC levels at 1-year follow-up were associated with LV remodeling and predicted its absence.
Conclusions:
- Rapid intracoronary EPC recruitment occurs early in STEMI, suggesting a reparative response.
- The extent of EPC mobilization is linked to infarct severity and MVO.
- Persistently low EPC levels are associated with adverse LV remodeling post-STEMI.
Abstract:
Endothelial progenitor cells (EPCs) are released from the bone marrow during cardiac ischemic events, potentially influencing vascular and myocardial repair. We assessed the clinical and angiographic correlates of EPC mobilization at the time of primary percutaneous coronary intervention in 78 patients with ST elevation myocardial infarction and the impact of both baseline and follow-up EPC levels on left ventricular (LV) remodeling. Blood samples were drawn from the aorta and the culprit coronary artery for cytofluorimetric EPC detection (CD34+CD45dimKDR+ cells, in percentage of cytofluorimetric counts). Area at risk was assessed by Bypass Angioplasty Revascularization Investigation myocardial jeopardy index, thrombotic burden as thrombus score and microvascular obstruction (MVO) as a combination of ST segment resolution and myocardial blush grade. Echocardiographic evaluation of LV remodeling was performed at 1-year follow-up in 54 patients, whereas peripheral EPC levels were reassessed in 40 patients. EPC levels during primary percutaneous coronary intervention were significantly higher in intracoronary than in aortic blood (0.043% vs 0.0006%, p <0.001). Both intracoronary and aortic EPC were related to area at risk extent, to intracoronary thrombus score (p <0.001), and inversely to MVO (p = 0.001). Peripheral EPC levels at 1-year follow-up were lower in patients with LV remodeling than in those without (0.001% [0.001 to 0.002] vs 0.003% [0.002 to 0.010]; p = 0.01) and independently predicted absence of remodeling at multivariate analysis. In conclusion, a rapid intracoronary EPC recruitment takes place in the early phases of ST elevation myocardial infarction, possibly reflecting an attempted reparative response. The extent of this mobilization seems to be correlated to the area at risk and to the amount of MVO. Persistently low levels of EPC are associated to LV remodeling.
