Steven A. Tamesis, MD, FACS

Steven A. Tamesis, MD, FACS is a Minimally Invasive Foregut and General Surgeon with Catholic Health Physician Partners, caring for patients at St. Catherine of Siena Hospital, St. Francis Hospital & Heart Center, and Good Samaritan University Hospital. He completed General Surgery residency training at UPMC–Mercy (University of Pittsburgh) and advanced fellowship training in Minimally Invasive Foregut Surgery at Allegheny Health Network – Esophageal Institute in Pittsburgh.

Dr. Tamesis specializes in the comprehensive management of GERD, hiatal/paraesophageal hernias, and complex foregut disorders using a physiology-based approach, with particular expertise in esophageal and gastric physiology testing to guide diagnosis and tailor therapy. His practice incorporates objective foregut evaluation—including high-resolution esophageal manometry, ambulatory pH and pH-impedance testing, and related functional assessments when indicated—to optimize outcomes and inform both endoscopic and surgical decision-making.

He has expertise and academic focus in advanced therapeutic endoscopy and third-space endoscopic surgery, including POEM (and variants) for esophageal motility disorders, G-POEM for selected gastric motility/pyloric dysfunction, and advanced endoscopic resection techniques—STER, ESD, and EFTR—for organ-preserving treatment of select esophageal and gastric tumors.

In addition to his clinical focus, he is deeply committed to resident and medical student education where he leads educational initiatives focused on surgical innovation, resident autonomy, and outcomes-driven care. He previously served as Program Director of the inaugural General Surgery Residency Program at Good Samaritan University Hospital/St. Catherine of Siena Hospital and now serves as Associate Program Director, as well as Surgical Clerkship Director at St. Catherine of Siena Hospital.