Abstract

Objectives: Clinical studies on intracoronary stem cell infusion in patients with acute myocardial infarction (AMI) revealed promising results concerning left ventricular ejection fraction (LVEF). However, intramyocardial cell injection has shown to be superior to the intracoronary approach in preclinical studies. This study was designed to test safety and feasibility of intramyocardial cell injection and left ventricular endocardial mapping (EMM) early after AMI.

Design: On day 10.5±5 after AMI and PCI with stent implantation (culprit lesion: 18 LCA, 2 RCA) 20 patients (mean 60.4±11.4 years) received bone marrow derived mononuclear cells (BMC) in the low voltage area using EMM-guided percutaneous intramyocardial injection. EMM and coronary angiogram was performed in 15 patients at 6-month follow-up. Echocardiography, laboratory data and clinical assessment (6-month and 12-month follow-up) were performed in all 20 patients.

Results: None of the patients showed periprocedural complications. Three patients received an ICD for primary prevention of sudden cardiac death and 6 (30%) patients showed in-stent restenosis. One patient underwent bypass surgery due to chronic stent occlusion after 6 months. We injected 2.0±0.3x10(8) cells including 1.0±0.3x10(6) CD45-/CD34+ stem cells in each patient. EMM showed an improvement from baseline UV 45.5±14.3% to 59.3±19.2% of normal voltage (p=0.002) and reduction of the low voltage area from 28.7±12% to 20.3±13.5% (p=0.016). During the 12-month follow-up, LVEF improved from 40.8±6.8% to 47,0±10,5%;(p=0.037).

Conclusion: Left ventricular electromechanical mapping and percutaneous intramyocardial cell injection in patients with AMI was shown to be a safe procedure. It is associated with improved LVEF and electromechanical parameters after a 12-month-follow-up.