Nikki Posnack Nikki Posnack
Associate Professor of Pediatrics
Associate Professor of Pharmacology and Physiology (Secondary)

Office Phone: 202-476-2475
Email: Email
Department: Pediatrics


  • BS, Washington College, 2004
  • PhD, George Washington University, 2009


While heart disease remains the leading cause of death in the United States – adverse environmental exposures are an understudied potential target to alleviate the risks of cardiovascular dysfunction. Dr. Posnack’s research is focused on identifying alterations in cardiac function due to environmental risk factors. Specifically, her research investigates the effects of endocrine-disrupting chemicals, which are commonly found in consumer products, medical devices, and the environment (i.e., air, dust, water). Perturbations in cardiovascular physiology are investigated using an array of models at the cellular (atrial, ventricular, human stem cell cardiomyocytes), three-dimensional (isolated hearts, engineered cardiac tissues), and whole animal level (prenatal exposure, cardiac injury). Dr. Posnack utilizes a variety of imaging modalities, molecular biology technologies, pharmacological assays and biomedical engineering approaches in her research.


Posnack, NG. 2014. Cardiovascular Toxicology. The adverse cardiac effects of Di(2-ethylhexyl)phthalate and Bisphenol A. PMID: 24811950

Posnack, NG., Jaimes, R., Asfour, H., Swift, L., Wengrowski, A., Sarvazyan, N., and M. Kay. 2014. 122(4): 384-390. Environmental Health Perspectives. Bisphenol A Exposure and Cardiac Electrical Conduction in Excised Rat Hearts.

Posnack, NG., Swift, L., Kay, M., Lee, N., and N. Sarvazyan. 2012. Environmental Health Perspectives. 120 (9): 1243-51. Phthalate exposure changes the metabolic profile of cardiac muscle cells.

Swift, L., Asfour, H., Posnack, NG., Arutunyan, A., Kay, M., and N. Sarvazyan. 2012. Pflügers Archives - European Journal of Physiology. 464(5): 503-512. Properties of blebbistatin in optical mapping of the heart and other imaging applications.

Posnack, NG., Brown, R., Lee, N., and N. Sarvazyan. 2011. Toxicology. 279 (1-3): 54-64. Gene expression profiling of DEHP-treated cardiomyocytes reveals potential causes of phthalate arrhythmogenicity.

Karabekian Z., Posnack NG., and N. Sarvazyan. 2011. Stem cell review and reports. 7 (2): 315-25. Immunological barriers to stem-cell based cardiac repair.

Gillum N., Karabekian, Z., Swift, L., Brown, R., Kay, M. and N. Sarvazyan. 2009. Toxicology and Applied Pharmacology. 236 (1): 25-38. Clinically relevant concentrations of Di (2-ethylhexyl) phthalate (DEHP) uncouple cardiac syncytium.

Karabekian Z., Gillum N., Wong E., and N. Sarvazyan. 2009. Cell Adhesion & Migration. 3 (3): 305-10. Effects of N-Cadherin overexpression on the adhesion properties of embryonic stem cells.

Gillum N., and N. Sarvazyan. 2008. Cardiovascular Toxicology. 8: 1-13. Adhesion proteins, stem cells and arrhythmogenesis.

Bakunts K., Gillum N., Karabekian Z., and N. Sarvazyan. 2008. Biotechniques. 44(3): 341-8. Formation of cardiac fibers in Matrigel matrix.

Industry Relationships and Collaborations

This faculty member (or a member of their immediate family) has reported a financial interest with the health care related companies listed below. These relations have been reported to the University and, when appropriate, management plans are in place to address potential conflicts.

  • None