Improved Heart Function after the Combined Treatment of Patients Undergoing Coronary Artery Bypass Grafting through Stem Cell Therapy and Transmyocardial Laser Revascularisation.

To improve tissue regeneration of ischemic myocardium, autologous bone marrow-derived stem cells have been injected intramyocardially in five patients undergoing coronary artery bypass grafting and transmyocardial laser revascularization. We have established an innovative method for the intraoperative isolation of CD133⁺-stem cells in less than 3 hours. After induction of general anesthesia, approx. 60 – 240 ml of bone marrow were harvested from the posterior iliac crest and processed in the operating room under GMP conditions using the automated cell selection device CliniMACS. Following standard coronary artery bypass grafting, laser channels were shot in predefined areas within the hibernating myocardium. Subsequently, autologous CD133⁺-stem cells (1.9–9.7 x 10⁶ cells; purity up to 97%) were injected in a predefined pattern around the laser channels (0.5–1.0x10⁶ cells/channel). Three months postoperatively, significant improvement of cardiac function as assessed by transthoracal echocardiography (ejection fraction before treatment: 25–30% - after treatment: 38–46%; left ventricular enddiastolic volume before treatment: 58 – 64 mm - after treatment: 40–44 mm; endsystolic wall thickness before treatment: 5–7 mm - after treatment 9–13 mm) and improvement of cardiac wall motion (electrocardiographically-triggered magnetic resonance imaging) were documented. This significant gain in heart function might be partly explained through the synergistic angiogenic effect of transmyocardial laser revascularization leading to a localized inflammatory response and the cellular effects of intramyocardially injected pluripotent bone marrow-derived stem cells promoting tissue repair. Through the intraoperative isolation of CD133⁺-cells, this effective treatment of ischemic myocardium can be applied to patients scheduled both for elective and for emergency revascularisation procedures.