Long term outcome after mononuclear bone marrow or peripheral blood cells infusion after myocardial infarction

Objectives This study reports the long-term follow-up of the randomised controlled HEBE trial. The HEBE study is a multicentre trial that randomised 200 patients with large first acute myocardial infarction (AMI) treated with primary percutaneous coronary intervention to either intracoronary infusion of bone marrow mononuclear cells (BMMCs) (n=69), peripheral blood mononuclear cells (PBMCs) (n=66) or standard therapy (n=65). Methods In addition to 3-5 days, and 4 months after AMI, all patients underwent cardiac MRI after 2 years. A follow-up for 5 years after AMI was performed to assess clinical adverse events, including death, myocardial reinfarction and hospitalisation for heart failure. Results Of the 200 patients enrolled, 9 patients died and 12 patients were lost to follow-up at 5 years after AMI. BMMC group showed less increase in LV enddiastolic volume (LVEDV) (3.5±16.9 mL/m²) compared with (11.2±19.8 mL/m2, p=0.03) in the control group, with no difference between the PBMC group (9.2 ±20.9 mL/m2) and controls (p=0.69). Moreover, the BMMC group showed a trend for decrease in LV end systolic volume (-1.8±15.0 mL/m²) as compared with controls (3.0±16.3 mL/m², p=0.07), with again no difference between PBMC (3.3±18.8 mL/m2) and controls (p=0.66). The combined endpoint of death and hospitalisation for heart failure was non-significantly less frequent in the BMMC group compared with the control group (n=4 vs n=1, p=0.20), with no difference between PBMC and controls (n=6 vs n=4, p=0.74). The composite endpoint of death or recurrent myocardial infarction was significantly higher in the PBMC group compared with controls (14 patients vs 3 patients, p=0.008), with no difference between the BMMC group and controls (2 vs 3 patients, p=0.67). Conclusions Long-term follow-up of the HEBE trial showed that increase in LVEDV was lower in the BMMC group. This study supports the long-term safety of intracoronary BMMC therapy. However, major clinical cardiovascular adverse events were significantly more frequent in the PBMC group.