Autologous Bone-Marrow Stem Cell Support in Acute Anterior Myocardial Infarction.

Purpose- Emerging evidence suggests that stem and progenitor cells derived from bone marrow can improve cardiac function and perhaps outcome in patients after acute myocardial infarction (AMI). In this single-centre randomised trial, we evaluated whether intracoronary transfer of autologous bone-marrow stem cells can affect not only global left ventricular (LV) function (nuclear scintigraphy) but also autonomic control (heart rate variability, HRV) and baroreflex sensitivity (BRS) at 12 months’ follow-up.

Methods- After successful percutaneous coronary intervention (PCI) for acute ST-segment elevation myocardial infarction and residual LV dysfunction, 33 patients were randomly assigned to either a control group (n=17) that received optimum postinfarction treatment, or a bone-marrow-stem-cell group (n=16) that received optimum treatment plus intracoronary infusion of autologous bone-marrow stem cells 4±1 days after PCI. Test analyses were done by two investigators blinded for treatment assignment.

Results- Global LVEF at baseline (determined 3±1 days after PCI) was 36.2±9.4 in controls and 35.1±9.8 in the bone-marrow cell group (P=NS). After 12 months, mean global LVEF had increased by 25% in the control group but 41% in the treated group with an anti-remodeling effect in the latter: LVEDV increased by 12% in the control vs 2% in the treated group (P<0.05). This was associated with improved HRV (SD −20ms vs +644 ms in the treated group P<0.01), particularly in the parasympathetic-related oscillation (HF +85.7±216 ms vs. +289.3±366 ms) and higher BRS (+3.4±11.7 vs +8.7±6.3 ms/mmHg) (control vs treated, P<0.05 in all comparisons). Cell transfer did not increase the risk of adverse clinical events, in-stent restenosis, or proarrhythmic effects. In 12 months follow-up 4 exitus (24%) were observed in the control group vs. only 1 (6%) in the treated group

Conclusions- The improvement of left-ventricular systolic function and prognosis in AMI patients by intracoronary transfer of autologous bone-marrow-cells may be mediated by higher vagal tone. (ClinicalTrials.gov number, NCT00437710).