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37 into cardiac myocytes has been demonstrated experimentally.17 As umbilical cord stem cells can be obtained without the need to sacrifice an embryo their isolation, use for research purposes and clinical application is not complicated by the ethical and political issues. 6. Amniotic stem (AFS) cell: DeCoppi et al reported the isolation of a new type of stem cell from amniotic fluid that has many characteristics of ESC without the ethical baggage.18 AFS cells seem to represent an intermediate stage between embryonic and adult stem cells in terms of their versatility. They are fully undifferentiated and pluripotent. Cell delivery. The three most frequently used routes in clinical setting are intracoronary infusion, percutaneous endocardial or direct intramyocardial injection during surgery. Intracoronary infusion requires migration through the vessel wall into the damaged tissue. Direct delivery of progenitor cells into scar tissue or areas of hibernating myocardium by catheter or surgical-based needle injection may generate relative higher local retention and less systemic distribution. Clinical trials. The most frequently tested cell types in clinical trials are skeletal myoblasts and bone-marrow or blood-derived progenitor cells. One major pitfall of using autologous cells is that the number of functional stem cells is generally depleted, with a markedly reduced proliferation potential in the elderly and in patients with cardiovascular disease. scientists and clinicians, developmental biologists and engineers, has led to a better understanding of the molecular signals and cues of cardiac regeneration. Despite the advances that have been made in this broad area, it is important to emphasize that there are still fundamental questions that need to be addressed both experimentally and clinically regarding potential features of cell repair. The most eminent unresolved issues are: cell delivery, optimization of cell retention, distribution, best route of delivery, time of transplantation, cell type, cell number, and viability of grafted cells. Hill et al 20 observed a strong correlation between the number of circulating EPCs and the subjects’ combined Framingham cardiovascular risk factor score. Therefore, with the onset of disease (or the presence of risk factors), the relevant cells appear to decrease in number and lose their reparative function. Despite the high number of stem cell studies performed, there is still no consensus on the optimal/minimal cell number required to achieve any effect. Much more work needs to be done before cellbased therapy can be used routinely in the clinical setting for people. ■ The authors can be contacted at nchronos@sjha.org Challenge and the future Cardiac tissue engineering, a novel concept, involves grafting ex vivo engineered heart muscle. This approach may theoretically allow complete replacement of diseased myocardium or reconstitution of cardiac malformations, but is still in its infancy.19 Stem cell treatment of the heart has not been shown to lead to the development of large-caliber coronary vessels, but rather to capillaries and arterioles by both angiogenesis and vasculogenesis. Therefore, stem cells are either used as adjunct to percutaneous coronary intervention or coronary artery bypass graft surgery, or in patients with angiographically-proven coronary artery disease without viable percutaneous or surgical treatment options. Knowledge, created by basic References 1. Hunt SA, Abraham WT, Chin MH, et al. ACC/AHA 2005 Guideline Update for the Diagnosis and Management of Chronic Heart Failure in the Adult — Summary Article: A Report of the American College of Cardiology/ American Heart Association Task Force on Practice Guidelines (Writing Committee to Update the 2001 Guidelines for the Evaluation and Management of Heart Failure): Developed in Collaboration With the American College of Chest Physicians and the International Society for Heart and Lung Transplantation: Endorsed by Heart Rhythm Society. Circulation 2005;112:1825–1852. 2. McAlister FA and Ezekowitz JA, N. Wiebe, et al. Systematic review: cardiac resynchronization in patients with symptomatic heart failure. Ann Intern Med 2004;141:381. 3. Lenzen MJ, Boersma E, Bertrand ME, et al. European Society of Cardiology: Management and outcome of patients with established coronary artery disease: the Euro Heart Survey on coronary revascularization. Eur Heart J 2005; 26: 1169–1179. 4. Lee MS and Makkar RR. Stem-cell transplantation in myocardial infarction: a status report. Ann Intern Med 2004;140:729. 5. Murry CE, Field LJ, Menasche P. Cellbased cardiac repair: reflections at the 10-year point. Circulation 2005; 112:3174. 6. Orlic D, Kajstura J, Chimenti S, et al. Bone marrow cells regenerate infarcted myocardium. Nature 2001;410: 701–705. 7. Goldman JM, Horowitz MM. The international bone marrow transplant registry. Int J Hematol 2002;76: 393–397. 8. Orlic D, Kajstura J, Chimenti S, et al. Mobilized bone marrow cells repair the infarcted heart, improving function and survival. Proc Natl Acad Sci U S A 2001;98:10344–10349. 9.Gehling UM, Ergun S, Schumacher U, et al. In vitro differentiation of endothelial cells from AC133-positive progenitor cells. Blood 2000;95:3106–3112. 10. Tavassoli M and Crosby WH. Transplantation of marrow to extramedullary sites. Science 1968; 161:54–56. 11. Conget PA and Minguell JJ. Phenotypical and functional properties of human bone marrow mesenchymal progenitor cells. J Cell Physiol 1999; 181:67–73. 12. Pittenger MF, Mackay AM, Beck SC, et al. Multilineage potential of adulthuman mesenchymal stem cells. Science 1999;284:143–147. 13. Azizi SA, Stokes D, Augelli BJ, et al. Engraftment and migration of human bone marrow stromal cells implanted in the brains of albino rats — similarities to astrocyte grafts. Proc Natl Acad Sci U S A 1998;95:3908–3913. 14. Makino S, Fukuda K, Miyoshi S, et al. Cardiomyocytes can be generated from marrow stromal cells in vitro. J Clin Invest 1999;103:697–705. 15. Beltrami AP, Barlucchi L, Torella D, et al. Adult cardiac stem cells are multipotent and support myocardial regeneration. Cell 2003;114:763. 16. Kehat I, Kenyagin-Karsenti D, Snir M, et al. Human embryonic stem cells can differentiate into myocytes with structural and functional properties of cardiomyocytes. J Clin Invest 2001;108: 407–414. 17. Kogler G, Sensken S, Airey JA, et al. A new human somatic stem cell from placental cord blood with intrinsic pluripotent differentiation potential. J Exp Med 2004;200:123–135. 18. De Coppi P, Bartsch Jr G, Siddiqui MM, et al. Isolation of amniotic stem cell lines with potential for therapy. Nat Biotech 2007;25:100–106. 19. Zimmermann WH, Melnychenko I, Wasmeier G, et al. Engineered heart tissue grafts improve systolic and diastolic function in infarcted rat hearts. Nat Med 2006;12,452–458. 20. Hill JM, Zalos G, Halcox JP, et al. Circulating endothelial progenitor cells, vascular function, and cardiovascular risk. N Engl J Med 2003;348:593–600. http://modulardevices.com http://modulardevices.com

Table of Contents Feed for the Digital Edition of Cath Lab Digest - March 2008

Cath Lab Digest - March 2008 Are You Being Paid Fair Market Value in 2008? A Cardiac Cath Lab Professionals Survey by Cath Lab Digest and the Society of Invasive Cardiovascular Professionals Saint Joseph’s Hospital Invasive Imaging Tools for Optimizing Coronary Stent Deployment Contents Clinical Editor’s Corner A Workflow Revolution in Cath Lab Reporting Advantages of a New Digital Lab at Baystate Medical Center Cardiac Computed Tomography: What Does it Mean for the Cath Lab? The Latest in Cardiac Magnetic Resonance Imaging (MRI) Cellular Cardiomyoplasty and Cardiac Regeneration Intravascular Ultrasound in the Cath Lab: A Powerful — and Underutilized — Tool to Improve Patient Outcomes The Stentplus™ Patient Success Program Cardiac Cath Lab Clutter — or, Spring into Action! Groin Bleeds and Other Hemorrhagic Complications of Cardiac Catheterization: A List of Relevant Issues Ask the Clinical Instructor: A Q&A Column for Those New to the Cath Lab What Do You Think? Experience with a New Guidewire: The Terumo Runthrough NS The Ostial Pro™ Stent Positioning System: Perfecting Aorto-Ostial Stent Placement Precious Minutes The Ten-Minute Interview with…Mark Bowles, BSN, CCRN Vascular Care in the Cath Lab: Planning a Smooth Transition Cath Laughs CMS 2008 OPPS Final Rule Review An Extensive Set of Review Courses for the CCI Basic Science, Non-Invasive Echocardiography and Vascular, and ARDMS Ultrasound Exams Meetings Calendar CEU Education Center Clinical & Industry News STEMI Interventions Classifieds Advertisers Index

Cath Lab Digest - March 2008

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