Simultaneous intramyocardial injection of autologous CD133+ bone marrow stemcells and mitral valve surgery in patients with cardiomyopathy

Objective: Intramyocardial transplantation of autologous bone marrow derived CD133+ stemcells (SC) in combination with CABG surgery has been shown to improve left ventricular function. As previously reported by our group, highly impaired left ventricular ejection fraction (LVEF) improved by 15%. Here we present the follow-up data from patients with cardiomyopathy who received simultaneous intramyocardial SC therapy and mitral valve surgery.

Methods: 10 patients with severe cardiomyopathy (8 ischemic/2 non ischemic) and concomitant mitral valve insufficiency were enrolled for the study. Stem cells were intraoperatively separated from bone marrow aspirates by immunomagnetic techniques. Clinical baseline data and results from echocardiography, Holter-electrocardiography and SPECT-perfusion-scan were analyzed preoperatively, before discharge and six month after surgery.

Results: The follow-up mortality was 0%. Mitral valve surgery (9 repairs, 1 replacement) and stem cell transplantation (SC-Tx) were performed simultaneously. Averagely, 6.7±3.4×10e6 CD133+ SC (purity 75%) were injected into the borderzone of scar tissue or into regions with poor contractility. No SC-Tx related complications were observed. After 6 month, there was an improvement in NYHA functional class from 2.6 to 1.9 (p=0.1). Interestingly, diagnostical evaluation did neither show a significant increase in LVEF (26.8±8.7% vs. 25.6±6.8%, p=0.7) nor an obvious decrease in left ventricular enddiastolic diameter (65.8±10mm vs. 67.3±10mm, p=0.7).

Conclusion: In this small series, the simultaneous mitral valve surgery and CD133+ SC-Tx did not show a comparable improvement in ventricular function as previously observed after CABG surgery and SC-Tx. The stage and aetiology of cardiomyopathy might essentially determine the outcome after SC-Tx.