Emerson C. Perin

Transendocardial, Autologous Bone Marrow Cell Transplantation for Severe, Chronic Ischemic Heart Failure

Background—This study evaluated the hypothesis that transendocardial injections of autologous mononuclear bone marrow cells in patients with end-stage ischemic heart disease could safely promote neovascularization and improve perfusion and myocardial contractility. Methods and Results—Twenty-one patients were enrolled in this prospective, nonrandomized, open-label study (first 14 patients, treatment; last 7 patients, control). Baseline evaluations included complete clinical and laboratory evaluations, exercise stress (ramp treadmill), 2D Doppler echocardiogram, single-photon emission computed tomography perfusion scan, and 24-hour Holter monitoring. Bone marrow mononuclear cells were harvested, isolated, washed, and resuspended in saline for injection by NOGA catheter (15 injections of 0.2 cc). Electromechanical mapping was used to identify viable myocardium (unipolar voltage ≥6.9 mV) for treatment. Treated and control patients underwent 2-month noninvasive follow-up, and treated patients alone underwent a 4-month invasive follow-up according to standard protocols and with the same procedures used as at baseline. Patient population demographics and exercise test variables did not differ significantly between the treatment and control groups; only serum creatinine and brain natriuretic peptide levels varied in laboratory evaluations at follow-up, being relatively higher in control patients. At 2 months, there was a significant reduction in total reversible defect and improvement in global left ventricular function within the treatment group and between the treatment and control groups (P =0.02) on quantitative single-photon emission computed tomography analysis. At 4 months, there was improvement in ejection fraction from a baseline of 20% to 29% (P =0.003) and a reduction in end-systolic volume (P =0.03) in the treated patients. Electromechanical mapping revealed significant mechanical improvement of the injected segments (P <0.0005) at 4 months after treatment. Conclusions—Thus, the present study demonstrates the relative safety of intramyocardial injections of bone marrow–derived stem cells in humans with severe heart failure and the potential for improving myocardial blood flow with associated enhancement of regional and global left ventricular function.

Mesenchymal Stem Cells Differentiate into an Endothelial Phenotype, Enhance Vascular Density, and Improve Heart Function in a Canine Chronic Ischemia Model

Background—Bone marrow–derived stem cells are under investigation as a treatment for ischemic heart disease. Mesenchymal stem cells (MSCs) have been used preferentially in the acute ischemia model; data in the chronic ischemia model are lacking. Methods and Results—Twelve dogs underwent ameroid constrictor placement. Thirty days later, they received intramyocardial injections of either MSCs (100×106 MSCs/10 mL saline) (n=6) or saline only (10 mL) (controls) (n=6). All were euthanized at 60 days. Resting and stress 2D echocardiography was performed at 30 and 60 days after ameroid placement. White blood cell count (WBC), C-reactive protein (CRP), creatine kinase MB (CK-MB), and troponin I levels were measured. Histopathological and immunohistochemical analyses were performed. Mean left ventricular ejection fraction was similar in both groups at baseline but significantly higher in treated dogs at 60 days. WBC and CRP levels were similar over time in both groups. CK-MB and troponin I increased from baseline to 48 hours, eventually returning to baseline. There was a trend toward reduced fibrosis and greater vascular density in the treated group. MSCs colocalized with endothelial and smooth muscle cells but not with myocytes. Conclusions—In a canine chronic ischemia model, MSCs differentiated into smooth muscle cells and endothelial cells, resulting in increased vascularity and improved cardiac function.

Improved Exercise Capacity and Ischemia 6 and 12 Months After Transendocardial Injection of Autologous Bone Marrow Mononuclear Cells for Ischemic Cardiomyopathy

Background—We recently reported the safety and feasibility of autologous bone marrow mononuclear cell (ABMMNC) injection into areas of ischemic myocardium in patients with end-stage ischemic cardiomyopathy. The present study evaluated the safety and efficacy of this therapy at 6- and 12-month follow-up. Methods and Results—Twenty patients with 6- and 12-month follow-up (11 treated subjects; 9 controls) were enrolled in this prospective, nonrandomized, open-label study. Complete clinical and laboratory evaluations as well as exercise stress (ramp treadmill), 2-dimensional Doppler echocardiography, single-photon emission computed tomography (SPECT) perfusion scanning, and 24-hour Holter monitoring were performed at baseline and follow-up. Transendocardial delivery of ABMMNCs was performed with the aid of electromechanical mapping to identify viable myocardium. Each patient received 15 ABMMNC injections of 0.2 mL each. At 6 and 12 months, total reversible defect, as measured by SPECT perfusion scanning, was significantly reduced in the treatment group as compared with the control group. At 12 months, exercise capacity was significantly improved in the treatment group. This improvement correlated well with monocyte, B-cell, hematopoietic progenitor cell, and early hemapoietic progenitor cell phenotypes. Conclusions—The 6- and 12-month follow-up data in this study suggest that transendocardial injection of ABMMNCs in patients with end-stage ischemic heart disease may produce a durable therapeutic effect and improve myocardial perfusion and exercise capacity.

Effect of transendocardial delivery of autologous bone marrow mononuclear cells on functional capacity, left ventricular function, and perfusion in chronic heart failure: the FOCUS-CCTRN trial.

CONTEXT Previous studies using autologous bone marrow mononuclear cells (BMCs) in patients with ischemic cardiomyopathy have demonstrated safety and suggested efficacy. OBJECTIVE To determine if administration of BMCs through transendocardial injections improves myocardial perfusion, reduces left ventricular end-systolic volume (LVESV), or enhances maximal oxygen consumption in patients with coronary artery disease or LV dysfunction, and limiting heart failure or angina. DESIGN, SETTING, AND PATIENTS A phase 2 randomized double-blind, placebo-controlled trial of symptomatic patients (New York Heart Association classification II-III or Canadian Cardiovascular Society classification II-IV) with a left ventricular ejection fraction of 45% or less, a perfusion defect by single-photon emission tomography (SPECT), and coronary artery disease not amenable to revascularization who were receiving maximal medical therapy at 5 National Heart, Lung, and Blood Institute-sponsored Cardiovascular Cell Therapy Research Network (CCTRN) sites between April 29, 2009, and April 18, 2011. INTERVENTION Bone marrow aspiration (isolation of BMCs using a standardized automated system performed locally) and transendocardial injection of 100 million BMCs or placebo (ratio of 2 for BMC group to 1 for placebo group). MAIN OUTCOME MEASURES Co-primary end points assessed at 6 months: changes in LVESV assessed by echocardiography, maximal oxygen consumption, and reversibility on SPECT. Phenotypic and functional analyses of the cell product were performed by the CCTRN biorepository core laboratory. RESULTS Of 153 patients who provided consent, a total of 92 (82 men; average age: 63 years) were randomized (n = 61 in BMC group and n = 31 in placebo group). Changes in LVESV index (-0.9 mL/m(2) [95% CI, -6.1 to 4.3]; P = .73), maximal oxygen consumption (1.0 [95% CI, -0.42 to 2.34]; P = .17), and reversible defect (-1.2 [95% CI, -12.50 to 10.12]; P = .84) were not statistically significant. There were no differences found in any of the secondary outcomes, including percent myocardial defect, total defect size, fixed defect size, regional wall motion, and clinical improvement. CONCLUSION Among patients with chronic ischemic heart failure, transendocardial injection of autologous BMCs compared with placebo did not improve LVESV, maximal oxygen consumption, or reversibility on SPECT. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00824005.

Effect of Intracoronary Delivery of Autologous Bone Marrow Mononuclear Cells 2 to 3 Weeks Following Acute Myocardial Infarction on Left Ventricular Function The LateTIME Randomized Trial

CONTEXT Clinical trial results suggest that intracoronary delivery of autologous bone marrow mononuclear cells (BMCs) may improve left ventricular (LV) function when administered within the first week following myocardial infarction (MI). However, because a substantial number of patients may not present for early cell delivery, the efficacy of autologous BMC delivery 2 to 3 weeks post-MI warrants investigation. OBJECTIVE To determine if intracoronary delivery of autologous BMCs improves global and regional LV function when delivered 2 to 3 weeks following first MI. DESIGN, SETTING, AND PATIENTS A randomized, double-blind, placebo-controlled trial (LateTIME) of the National Heart, Lung, and Blood Institute-sponsored Cardiovascular Cell Therapy Research Network of 87 patients with significant LV dysfunction (LV ejection fraction [LVEF] ≤45%) following successful primary percutaneous coronary intervention (PCI) between July 8, 2008, and February 28, 2011. INTERVENTIONS Intracoronary infusion of 150 × 10(6) autologous BMCs (total nucleated cells) or placebo (BMC:placebo, 2:1) was performed within 12 hours of bone marrow aspiration after local automated cell processing. MAIN OUTCOME MEASURES Changes in global (LVEF) and regional (wall motion) LV function in the infarct and border zone between baseline and 6 months, measured by cardiac magnetic resonance imaging. Secondary end points included changes in LV volumes and infarct size. RESULTS A total of 87 patients were randomized (mean [SD] age, 57 [11] years; 83% men). Harvesting, processing, and intracoronary delivery of BMCs in this setting was feasible. Change between baseline and 6 months in the BMC group vs placebo for mean LVEF (48.7% to 49.2% vs 45.3% to 48.8%; between-group mean difference, -3.00; 95% CI, -7.05 to 0.95), wall motion in the infarct zone (6.2 to 6.5 mm vs 4.9 to 5.9 mm; between-group mean difference, -0.70; 95% CI, -2.78 to 1.34), and wall motion in the border zone (16.0 to 16.6 mm vs 16.1 to 19.3 mm; between-group mean difference, -2.60; 95% CI, -6.03 to 0.77) were not statistically significant. No significant change in LV volumes and infarct volumes was observed; both groups decreased by a similar amount at 6 months vs baseline. CONCLUSION Among patients with MI and LV dysfunction following reperfusion with PCI, intracoronary infusion of autologous BMCs vs intracoronary placebo infusion, 2 to 3 weeks after PCI, did not improve global or regional function at 6 months. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00684060.

Adipose-derived regenerative cells in patients with ischemic cardiomyopathy: The PRECISE Trial.

AIMS Adipose-derived regenerative cells (ADRCs) can be isolated from liposuction aspirates and prepared as fresh cells for immediate administration in cell therapy. We performed the first randomized, placebo-controlled, double-blind trial to examine the safety and feasibility of the transendocardial injections of ADRCs in no-option patients with ischemic cardiomyopathy. METHODS AND RESULTS Procedural, postoperative, and follow-up safety end points were monitored up to 36 months. After baseline measurements, efficacy was assessed by echocardiography and single-photon emission computed tomography (6, 12, and 18 months), metabolic equivalents and maximal oxygen consumption (MVO2) (6 and 18 months), and cardiac magnetic resonance imaging (6 months). We enrolled 21 ADRC-treated and 6 control patients. Liposuction was well tolerated, ADRCs were successfully prepared, and transendocardial injections were feasible in all patients. No malignant arrhythmias were seen. Adverse events were similar between groups. Metabolic equivalents and MVO2 values were preserved over time in ADRC-treated patients but declined significantly in the control group. The difference in the change in MVO2 from baseline to 6 and 18 months was significantly better in ADRC-treated patients compared with controls. The ADRC-treated patients showed significant improvements in total left ventricular mass by magnetic resonance imaging and wall motion score index. Single-photon emission computed tomography results suggested a reduction in inducible ischemia in ADRC-treated patients up to 18 months. CONCLUSION Isolation and transendocardial injection of autologous ADRCs in no-option patients were safe and feasible. Our results suggest that ADRCs may preserve ventricular function, myocardial perfusion, and exercise capacity in these patients.

Assessing Myocardial Viability and Infarct Transmurality With Left Ventricular Electromechanical Mapping in Patients With Stable Coronary Artery Disease Validation by Delayed-Enhancement Magnetic Resonance Imaging

Background—This study was designed to define myocardial viability and establish practical cut-off values for differentiating normal myocardial tissue from subendocardial and transmural scar tissue by using electromechanical mapping (EMM). We validated our results by delayed-enhancement cardiac MRI (DE-MRI). Methods and Results—We prospectively studied 15 ambulatory patients with stable coronary disease who were candidates for cardiac catheterization. Within 48 hours of EMM, DE-MRI was performed. Using EMM software, we created a bull’s eye precisely matched to that generated by DE-MRI. Segment by segment, we compared the MRI results to the corresponding unipolar voltage value for that same segment in the EMM bull’s eye. Of 300 total segments, 275 were compared. The segments were divided into normal (n=211), subendocardial scar (n=49), and transmural scar (n=15). We found that subendocardial (6.8±2.9 mV) and transmural (4.6±1.9 mV) scar segments had significantly less unipolar voltage than normal (11.6±4.5 mV) segments (P <0.05 for each comparison). When normal myocardium was compared with myocardium with subendocardial scar, the threshold for differentiating between the two areas was 7.9 mV (sensitivity, 80%; specificity, 80%). Comparison of normal tissue to transmural scar yielded a threshold of 6.9 mV (sensitivity, 93%; specificity, 88%). Conclusions—Our results demonstrate that normal myocardium can be accurately distinguished from myocardium with subendocardial or transmural infarcts on the basis of unipolar voltage values obtained through EMM. This is the first study to validate these results by using cardiac DE-MRI in humans.

Adult Stem Cell Therapy in Perspective

Ventricular remodeling and ultimately heart failure are the inexorable consequences of substantial myocardial infarction. In recent years, the understanding that regenerative processes exist at the level of the myocardium has placed stem cell research at center stage in cardiology. Through cellular therapies, the concept of “growing” heart muscle and vascular tissue and manipulating the myocardial cellular environment has revolutionized the approach to treating heart disease. Unfortunately, however, the vast field of possibilities opened by stem cell therapy has frequently given rise to more questions than answers. A few of these questions include: Which patients with cardiovascular diseases should be considered for stem cell therapy? Which type of stem cell(s) should be used? What quantity and concentration of cells should be administered? By what mechanisms do stem cells engraft, survive, and differentiate? Is the functional and morphological cardiac improvement achieved actively (ie, by increasing contractility) or passively (ie, by limiting infarct expansion and remodeling)? What is the lifespan of transplanted stem cells in the heart? How safe is this therapy, and is there potential tumorigenesis of stem cells? What might be the potential benefits of cell transplantation in nonischemic heart failure? In this report, we wish to review available information about cardiovascular stem cell therapy, share our early experience in this new field, and speculate about future directions. Although embryonic stem cells have been shown to have greater potency for proliferation and differentiation than adult stem cells, their lack of availability and ethical issues hamper clinical applications. This report will, therefore, focus on the therapeutic applications of adult stem cells. The diverse literature on stem cell research comprises the work of basic and clinical scientists from many different subspecialties. This may account for the heterogeneous mixture of models, methods, types, quantity, and nature of the cells employed and the timing of …

CD34+ cell infusion after ST elevation myocardial infarction is associated with improved perfusion and is dose dependent

BACKGROUND the objective of the study was to determine whether the effects of infarct-related artery (IRA) infusion of autologous bone marrow-derived CD34(+) cells after ST elevation myocardial infarction (STEMI) are dependent on the dose (quantity and mobility) of the cells infused. Beneficial effects of IRA infusion of mononuclear cells after STEMI have been inconsistent, possibly because of differences in timing, cell type, quantity, and mobility of infused cells. METHODS patients were randomized to bone marrow harvest (n = 16) or control (n = 15). At a median of 8.3 days after coronary stenting for STEMI, CD34(+) cells were infused via the IRA at 3 dose levels (5, 10, and 15 × 10(6)) in cohorts of 5 patients each. Baseline and follow-up imaging and ex vivo CD34(+) cell mobility were performed. RESULTS Cell harvest and infusion were safe. Quantitative rest hypoperfusion score measured by single-photon emission computed tomography improved at 6 months in the ≥ 10 million cohorts compared with controls (-256 vs +14, P = .02). There was a trend toward improved ejection fraction at 6 months (+4.5%) in the ≥ 10 million cohorts compared with no change in the controls and 5 million cohort (+0.7%). Improved perfusion and infarct size reduction correlated with the quantity and mobility of the infused CD34(+) cells. CONCLUSIONS the effects of CD34(+) cell IRA infusion during the repair phase after STEMI are dose dependent and, at a threshold dose of 10 million CD34(+) cells, associated with a significant improvement in perfusion that may limit deterioration in cardiac function (IRA infusion of CD34(+) cells in patients with acute myocardial infarction [AMR-01] NCT00313339).

Transendocardial autologous bone marrow mononuclear cell injection in ischemic heart failure: postmortem anatomicopathologic and immunohistochemical findings.

Background—Cell-based therapies for treatment of ischemic heart disease are currently under investigation. We previously reported the results of a phase I trial of transendocardial injection of autologous bone marrow mononuclear (ABMM) cells in patients with end-stage ischemic heart disease. The current report focuses on postmortem cardiac findings from one of the treated patients, who died 11 months after cell therapy. Methods and Results—Anatomicopathologic, morphometric, and immunocytochemical findings from the anterolateral ventricular wall (with cell therapy) were compared with findings from the interventricular septum (normal perfusion and no cell therapy) and from the inferoposterior ventricular wall (extensive scar tissue and no cell therapy). No signs of adverse events were found in the cell-injected areas. Capillary density was significantly higher (P<0.001) in the anterolateral wall than in the previously infarcted tissue in the posterior wall. The prominent vasculature of the anterolateral wall was associated with hyperplasia of pericytes, mural cells, and adventitia. Some of these cells had acquired cytoskeletal elements and contractile proteins (troponin, sarcomeric &agr;-actinin, actinin), as well as the morphology of cardiomyocytes, and appeared to have migrated toward adjacent bundles of cardiomyocytes. Conclusions—Eleven months after treatment, morphological and immunocytochemical analysis of the sites of ABMM cell injection showed no abnormal cell growth or tissue lesions and suggested that an active process of angiogenesis was present in both the fibrotic cicatricial tissue and the adjacent cardiac muscle. Some of the pericytes had acquired the morphology of cardiomyocytes, suggesting long-term sequential regeneration of the cardiac vascular tree and muscle.