Steven Poelzing, Ph.D.
- Cardiovascular engineering
Sudden cardiac death is a significant cause of mortality in the United States and around the world. There is an increasing awareness that sudden cardiac death is linked to genetic mutations in cardiac proteins, or changes in those same proteins during diseases such as heart failure, ischemia, or diabetes.
One cardiac gap junction protein of interest, Connexin43, or Cx43, allows the spread of electrical activity between cardiac myocytes for the purpose of coordinating uniform and synchronized contraction. Conventional theory suggests that reducing Cx43 expression should slow the spread of electrical activity—conduction—in the heart and increase risk of arrhythmias leading to sudden death. The experimental relationships between conduction slowing, sudden cardiac death, and loss of Cx43 is not straightforward, however, and conflicting laboratory findings have led to a lack of experimental agreement on the degree of conduction slowing expected from a quantifiable reduction of Cx43.
Steven Poelzing hypothesizes that the spread of electrical activity between cardiac myocytes is not only mediated through connexins, but also through electric fields between myocytes. His laboratory has demonstrated that the hydration state of the heart can mask or unmask conduction slowing in the presence of reduced Cx43 expression. Poelzing’s group uses high-resolution optical mapping, isolated cellular electrophysiological measurements, and immunohistochemistry to determine the mechanisms of non-gap junction–mediated conduction and its dependence on Cx43 and the gap junction. In particular, Poelzing is seeking to determine how pathological insults such as cardiac inflammation and edema modulate the risk of sudden death in the young and how age changes this relationship.
- MetroHealth Medical Center: Postdoctoral fellowship
- Case Western Reserve University: Ph.D., Biomedical Engineering
- Case Western Reserve University: M.S.E., Biomedical Engineering
- Wright State University: B.S., Biomedical Engineering
Awards, Honors and Services
- Fellow, Heart Rhythm Society, 2015
- Fellow, American Heart Association, 2014
- Editorial Board, Frontiers in Cardiac Electrophysiology editorial board, 2010-Present
- Top Instructors in Engineering, University of Utah, 2008, 2009, 2010, 2011
- Michael Bilitch Fellowship in Cardiac Pacing and Electrophysiology, Heart Rhythm Society, 2004
- Rammelkamp Research Days, 1st Place Oral Presentation Presentation, MetroHealth Med. Center, 2004
- National Institutes of Health National Research Award, Case Western Reserve University, 1997-1999
Veeraraghavan R, Lin J, Keener JP, Gourdie RG, Poelzing S. (2016). Potassium Channels in the Cx43 Gap Junction Perinexus Modulate Ephaptic Coupling: An Experimental and Modeling Study. Pflugers Archiv.
Abdullah OM, Gomez AD, Merchant S, Heidinger M, Poelzing S, Hsu EW. (2015). Orientation dependence of microcirculation-induced diffusion signal in anisotropic tissues. Magnetic Resonance in Medicine.
Veeraraghavan R, Lin J, Hoeker GS, Keener JP*, Gourdie RG*, Poelzing S*. (2015). Sodium channels in the Cx43 gap junction perinexus may constitute a cardiac ephapse: an experimental and modeling study. Pflugers Archive - European Journal of Physiology.
Greer-Short A, Poelzing S. (2015). Temporal response of ectopic activity in guinea pig ventricular myocardium in response to isoproterenol and acetylcholine. Frontiers in Physiology 6.
Varano AC, Rahimi A, Dukes MJ, Poelzing S, McDonald SM, Kelly DF. (2015). Visualizing virus particle mobility in liquid at the nanoscale. Chemical Communications 2: 1-6.
Radwański PB, Brunello L, Veeraraghavan R, Ho H, Lou Q, Makara MA, Belevych AE, Anghelescu M, Priori SG, Volpe P, Hund TJ, Janssen PM, Mohler PJ, Bridge JH, Poelzing S, Györke S. (2014). Neuronal Na+ Channel Blockade Suppresses Arrhythmogenic Diastolic Ca2+ Release. Cardiovascular Research.
Veeraraghavan R, Poelzing S, Gourdie RG. (2014). Novel ligands for zipping and unzipping the intercalated disk: today's experimental tools, tomorrow's therapies? Cardiovasc Res 104(2): 229-30.
Veeraraghavan R, Poelzing S, Gourdie RG. (2014). Intercellular electrical communication in the heart: a new, active role for the intercalated disk. Cell Commun Adhes.
Veeraraghavan R, Gourdie RG, Poelzing S. (2014). Mechanisms of Cardiac Conduction: A History of Revisions. Am J Physiol Heart Circ Physiol 306(5): H619-27.
Veeraraghavan R, Poelzing S, Gourdie RG. (2014). Old Cogs, New Tricks: A Scaffolding Role For Connexin43 And A Junctional Role For Sodium Channels?. FEBS Lett.