Key Points Question What is the clinical significance of clonal hematopoiesis of indeterminate potential (CHIP) for chronic heart failure (CHF) owing to ischemic origin? Findings In this cohort study, CHIP had a high prevalence in 200 investigated patients with CHF. While no clinical baseline characteristics associated with CHF were different between CHIP carriers and non-CHIP carriers, except for the mean age, harboring mutations in the most prevalent driver genes associated with CHIP, namely DNMT3A and TET2 , was associated with a significant and profound increase in death and rehospitalization for heart failure. Meaning Clonal hematopoiesis of indeterminate potential is presented as a newly identified risk factor for impaired long-term survival and increased disease progression in patients with CHF that may be well targetable as a valuable approach to precision medicine in patients with CHF carrying specific mutations encoding for clonal hematopoiesis.

Aims Somatic mutations of the epigenetic regulators DNMT3A and TET2 causing clonal expansion of haematopoietic cells (clonal haematopoiesis; CH) were shown to be associated with poor prognosis in chronic ischaemic heart failure (CHF). The aim of our analysis was to define a threshold of variant allele frequency (VAF) for the prognostic significance of CH in CHF. Methods and results We analysed bone marrow and peripheral blood-derived cells from 419 patients with CHF by error-corrected amplicon sequencing. Cut-off VAFs were optimized by maximizing sensitivity plus specificity from a time-dependent receiver operating characteristic (ROC) curve analysis from censored data. 56.2% of patients were carriers of a DNMT3A- (N = 173) or a TET2- (N = 113) mutation with a VAF >0.5%, with 59 patients harbouring mutations in both genes. Survival ROC analyses revealed an optimized cut-off value of 0.73% for TET2- and 1.15% for DNMT3A-CH-driver mutations. Five-year-mortality was 18% in patients without any detected DNMT3A- or TET2 mutation (VAF < 0.5%), 29% with only one DNMT3A- or TET2-CH-driver mutations above the respective cut-off level and 42% in patients harbouring both DNMT3A- and TET2-CH-driver mutations above the respective cut-off levels. In carriers of a DNMT3A mutation with VAF ≥ 1.15%, 5-year mortality was 31%, compared with 18% mortality in those with VAF < 1.15% (P = 0.048). Likewise, in patients with TET2 mutations, 5-year mortality was 32% with VAF ≥ 0.73%, compared with 19% mortality with VAF < 0.73% (P = 0.029). Conclusion The present study defines novel threshold levels for clone size caused by acquired somatic mutations in the CH-driver genes DNMT3A and TET2 that are associated with worse outcome in patients with CHF.

Objective-Bone marrow-derived mononuclear cells (BMCs) improve the functional recovery after ischemia. However, BMCs comprise a heterogeneous mixture of cells, and it is not known which cell types are responsible for the induction of neovascularization after cell therapy. Because cell recruitment is critically dependent on the expression of the SDF-1-receptor CXCR4, we examined whether the expression of CXCR4 may identify a therapeutically active population of BMCs. Methods and Results-Human CXCR4ϩ and CXCR4 Ϫ BMCs were sorted by magnetic beads. CXCR4 ϩ BMCs showed a significantly higher invasion capacity under basal conditions and after SDF-1 stimulation. Hematopoietic or mesenchymal colony-forming capacity did not differ between CXCR4 ϩ and CXCR4 Ϫ BMCs. Injection of CXCR4ϩ BMCs in mice after induction of hindlimb ischemia significantly improved the recovery of perfusion compared to injection of CXCR4 Ϫ BMCs. Likewise, capillary density was significantly increased in CXCR4 ϩ BMC-treated mice. Because part of the beneficial effects of cell therapy were attributed to the release of paracrine effectors, we analyzed BMC supernatants for secreted factors. Importantly, supernatants of CXCR4 ϩ BMCs were enriched in the proangiogenic cytokines HGF and PDGF-BB. Conclusion-CXCR4ϩ BMCs exhibit an increased therapeutic potential for blood flow recovery after acute ischemia. Mechanistically, their higher migratory capacity and their increased release of paracrine factors may contribute to enhanced tissue repair. espite improved interventional and pharmacological therapy, postinfarction heart failure remains a challenge in patients with large myocardial infarctions. 1,2 Cell therapy may provide a novel therapeutic option to modify left ventricular remodeling processes and prevent postinfarction heart failure. Several clinical pilot trials and randomized studies showed beneficial effects of cell therapy on left ventricular ejection fraction. 3 In addition, intracoronary administration of bone marrow-derived mononuclear cells (BMCs) was shown to be associated with a significant reduction of the occurrence of major adverse cardiovascular events after AMI. 4 Most of the clinical studies used BMCs isolated from bone marrow aspirates by density gradient centrifugation for intracoronary cell therapy (for review see 5,6 ). BMCs comprise a heterogeneous mixture of cells containing endothelial progenitor cells (EPCs), hematopoietic progenitor cells, mesenchymal stem cells (MSCs), multipotent adult mesenchymal progenitors, and very small embryonic-like (VSEL) stem cells. Although various studies provide evidence that selected endothelial/hematopoietic progenitor cells expressing the marker CD34 or CD133, 7,8 cultured MSCs, 9 -11 and VSEL cells 12 improve the recovery after acute myocardial infarction, the subsets of cells responsible for these beneficial effects of total BMCs are not yet identified.The chemokine stromal cell-derived factor-1 (SDF-1) and its specific receptor, CXCR4, play a pivotal role in normal cardiovascular develop...

Rationale: Cell therapy is a promising option for the treatment of acute or chronic myocardial ischemia. The intracoronary infusion of cells imposes the potential risk of cell clotting, which may be prevented by the addition of anticoagulants. However, a comprehensive analysis of the effects of anticoagulants on the function of the cells is missing.Objective: Here, we investigated the effects of heparin and the thrombin inhibitor bivalirudin on bone marrow-derived mononuclear cell (BMC) functional activity and homing capacity. Methods and Results: