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Updated: May 12, 2026
Postconditioning with Lactate-enriched Blood for Cardioprotection in ST-segment Elevation Myocardial Infarction
Published on: May 28, 2019
Long-term impact of postconditioning on infarct size and left ventricular ejection fraction in patients with
Peder Sörensson1, Lars Rydén, Nawsad Saleh
1Karolinska Institutet, Department of Medicine, Unit of Cardiology, Karolinska University Hospital, Stockholm, Sweden. peder.sorensson@karolinska.se
Insights
Ischemic postconditioning (PostC) did not reduce infarct size or improve ejection fraction in STEMI patients long-term. However, PostC showed benefits for patients with large myocardium at risk, extending previous short-term findings.
Area of Science:
- Cardiology
- Interventional Cardiology
- Myocardial Infarction Research
Background:
- Ischemic postconditioning (PostC) involves brief reperfusion cycles to reduce infarct size in ST-elevation myocardial infarction (STEMI).
- Previous studies indicated short-term benefits of PostC, particularly in patients with large myocardium at risk (MaR).
Purpose of the Study:
- To investigate the long-term effects of PostC on infarct size and left ventricular ejection fraction (LVEF) in STEMI patients.
- To determine if PostC provides sustained benefits beyond initial observations.
Main Methods:
- Sixty-eight STEMI patients were randomized to primary percutaneous coronary intervention (PCI) or PCI followed by PostC.
- Infarct size and LVEF were assessed using cardiac magnetic resonance imaging at 3 and 12 months post-intervention.
- Myocardium at risk (MaR) was defined by abnormally contracting segments on left ventricular angiograms.
Main Results:
- Overall, no significant difference in infarct size (as % of MaR) or LVEF was observed between PostC and control groups at 12 months.
- Patients in the PostC group with MaR in the upper quartile demonstrated significantly smaller infarct size compared to controls (p < 0.05).
- In the subgroup with large MaR, LVEF was significantly higher in the PostC group than in the control group at 12 months (p < 0.01).
Conclusions:
- Long-term PostC did not reduce infarct size relative to MaR or improve LVEF in the overall STEMI population.
- The study suggests that PostC may offer sustained beneficial effects specifically in STEMI patients with large myocardium at risk.
- These findings extend previous short-term observations regarding the efficacy of PostC in a select group of STEMI patients.
Background:
Ischemic postconditioning (PostC), reperfusion in brief cycles, is known to induce short-term reduction in infarct size in patients with ST elevation myocardial infarction (STEMI), especially among those with large myocardium at risk (MaR). The aim of the present study was to investigate the long-term effect of PostC on infarct size and left ventricular ejection fraction (LVEF).
Methods:
Sixty-eight patients with a first STEMI were randomised to primary percutaneous coronary intervention (PCI) (n = 35) or PCI followed by PostC (n = 33). MaR was determined as abnormally contracting segments on left ventricular angiogram. Cardiac magnetic resonance was performed at 3 and 12 months for the determination of infarct size and LVEF.
Results:
Overall there was no difference in infarct size expressed in percentage of MaR between patients randomised to the control (31%; 23, 41) and PostC (31%; 23, 43) groups at 12 months. Likewise there was no difference in LVEF between control (49%; 41, 55) and PostC (52%; 45, 55). In contrast, patients in the PostC group with MaR in the upper quartile had a significantly smaller infarct size (29%; 18, 38) than those in the control group (40%; 34, 48; p < 0.05) at 12 months. In these patients LVEF was higher in the PostC (47%; 43, 50) compared to the control group (38%; 34, 42; p < 0.01).
Conclusions:
In this long-term follow-up study PostC did not reduce infarct size in relation to MaR or improved LVEF in the overall study population. However, the present data suggest that PostC exerts long-term beneficial effects in patients with large MaR thereby extending previously published short-term observations.
Trial Registration:
Karolinska Clinical Trial Registration (http://www.kctr.se). Unique identifier: CT20080014.
