Homsy, Christian

Abstract Aims Left ventricular (LV) reverse remodelling is an important marker of improved outcomes in patients with advanced heart failure (HF). We examined the impact of the intramyocardial administration of bone-marrow-derived, lineage-directed, autologous cardiopoietic mesenchymal stem cells (C3BS-CQR-1) on LV remodelling in patients with advanced HF enrolled in the CHART-1 study. Methods and results Patients (n=351) with symptomatic advanced HF secondary to ischaemic heart disease, and reduced LV ejection fraction (LVEF <35%) were randomized to receive C3BS-CQR-1 or a sham procedure. In a post hoc analysis we examined the effect of C3BS-CQR-1 on LV reverse remodelling within 1 year of the procedure and the influence of C3BS-CQR-1 dosing in the 271 patients treated as randomized. Delivery of C3BS-CQR-1 was associated with a progressive decrease in both LV end-diastolic volume (LVEDV) and end-systolic volume (LVESV) within 52 weeks after treatment. At 1 year, the LVEDV and LVESV of treated patients decreased by 17.0 mL and 12.8 mL greater than controls (P=0.006 and P=0.017, respectively). The effect on LVEDV was maintained after multivariable adjustment for baseline age, systolic blood pressure, LVEDV, LVEF and history of myocardial infarction. The largest reverse remodelling was evident in the patients receiving a moderate number of injections (<20). Conclusion In CHART-1, intramyocardial administration of cardiopoietic stem cells led to reverse remodelling as evidenced by significant progressive decreases in LVEDV and LVESV through the 52 weeks of follow-up. Further studies are needed to explore the dose response with regard to cell number and injected volume, and reverse remodelling.

Abstract Aims Cardiopoiesis is a conditioning programme that aims to upgrade the cardioregenerative aptitude of patient-derived stem cells through lineage specification. Cardiopoietic stem cells tested initially for feasibility and safety exhibited signs of clinical benefit in patients with ischaemic heart failure (HF) warranting definitive evaluation. Accordingly, CHART-1 is designed as a large randomized, sham-controlled multicentre study aimed to validate cardiopoietic stem cell therapy. Methods Patients (n = 240) with chronic HF secondary to ischaemic heart disease, reduced LVEF (<35%), and at high risk for recurrent HF-related events, despite optimal medical therapy, will be randomized 1:1 to receive 600 × 106 bone marrow-derived and lineage-directed autologous cardiopoietic stem cells administered via a retention-enhanced intramyocardial injection catheter or a sham procedure. The primary efficacy endpoint is a hierarchical composite of mortality, worsening HF, Minnesota Living with Heart Failure Questionnaire score, 6 min walk test, LV end-systolic volume, and LVEF at 9 months. The secondary efficacy endpoint is the time to cardiovascular death or worsening HF at 12 months. Safety endpoints include mortality, readmissions, aborted sudden deaths, and serious adverse events at 12 and 24 months. Conclusion The CHART-1 clinical trial is powered to examine the therapeutic impact of lineage-directed stem cells as a strategy to achieve cardiac regeneration in HF populations. On completion, CHART-1 will offer a definitive evaluation of the efficacy and safety of cardiopoietic stem cells in the treatment of chronic ischaemic HF. Trial registration: NCT01768702

Background— Regenerative cell-based therapies are associated with limited myocardial retention of delivered stem cells. The objective of this study is to develop an endocardial delivery system for enhanced cell retention. Methods and Results— Stem cell retention was simulated in silico using 1- and 3-dimensional models of tissue distortion and compliance associated with delivery. Needle designs, predicted to be optimal, were accordingly engineered using nitinol, a nickel and titanium alloy displaying shape memory and superelasticity. Biocompatibility was tested with human mesenchymal stem cells. Experimental validation was performed with species-matched cells directly delivered into Langendorff-perfused porcine hearts or administered percutaneously into the endocardium of infarcted pigs. Cell retention was quantified by flow cytometry and real-time quantitative polymerase chain reaction methodology. Models, computing optimal distribution of distortion calibrated to favor tissue compliance, predicted that a 75°-curved needle featuring small-to-large graded side holes would ensure the highest cell retention profile. In isolated hearts, the nitinol curved needle catheter (C-Cath) design ensured 3-fold superior stem cell retention compared with a standard needle. In the setting of chronic infarction, percutaneous delivery of stem cells with C-Cath yielded a 37.7±7.1% versus 10.0±2.8% retention achieved with a traditional needle without effect on biocompatibility or safety. Conclusions— Modeling-guided development of a nitinol-based curved needle delivery system with incremental side holes achieved enhanced myocardial stem cell retention.