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New physicians join St. John's Physician Practices

St. John’s Physician Practices announces that two physicians will join the medical group: William Mullen, MD, has joined St. John’s Cardiology and Tierney Lake, MD, has joined St. John’s Internal Medicine.

“These physicians bring a high degree of expertise and compassion to our team,” said John Payne, DO, medical director of St. John’s Physician Practices, which encompasses nine primary and specialty clinics. “With the addition of these physicians, we will be able to better serve the primary and specialty care needs of our community.”


The addition of cardiologist William Mullen, MD, to St. John’s Cardiology enhances the medical center’s program for the detection and treatment of heart disease. Dr. Mullen is board certified in cardiovascular disease and has practiced at the Palo Alto Medical Foundation in California since 1994. His professional interests include arrhythmia, heart failure, myocardial infarction, and non-invasive cardiac testing. Cardiology services at St. John’s range from echocardiograms to cardiac rehabilitation.

Heart patients will also continue to benefit from the services offered by the visiting cardiac specialists from Intermountain Health Care (Salt Lake City, UT), with whom St. John's has had a long-standing relationship. They have privileges to practice medicine at St. John’s Medical Center, and Dr. Mullen will have privileges at Intermountain Health Care, facilitating smooth coordination of patient care between St. John’s and the advanced services offered at larger facilities in Salt Lake.

Dr. Mullen earned his medical degree from Tulane University. His residency was at Highland General Hospital in California, and he completed a fellowship in cardiology at University of California-San Francisco. Dr. Mullen has ties to the Jackson area and assisted with St. John’s teen athlete heart screening last fall. He enjoys skiing, biking, and spending time with his three grown children.

To schedule an appointment with Dr. Mullen, call St. John’s Cardiology at 307.739.7690.

Internal Medicine

With the recent retirement of internist Dr. Dennis Butcher, St. John’s Internal Medicine hired Tierney Lake, MD, to join its Jackson office, where she will practice with Hayley Miller, MD, and Calvin Schenk, PA-C.

Internal medicine doctors provide primary care to adults over 18, and are trained to prevent, diagnose, and treat adult diseases.

Board certified in internal medicine, Dr. Lake received her medical degree from the University of Colorado in Aurora, where she also completed her internal medicine residency. Prior to accepting the position at St. John’s, Dr. Lake practiced outpatient internal medicine at Montrose Medicine and worked as a hospitalist at Montrose Memorial Hospital in Colorado. Dr. Lake is an outdoor enthusiast who enjoys spending her free time trail running, mountain biking, backpacking, and skiing with her husband and two labs.

To schedule an appointment with Dr. Lake, call St. John’s Internal Medicine at 307.733.7222.


Media contact: Karen Connelly, 739 7380,

St. John's Medical Center in Jackson, Wyoming, offers patient-centered clinical excellence and community wellness services through a full-service hospital, primary care, and specialty physician practices, and a long-term care Living Center.

The mission of <a href=""> St. John’s Hospital Foundation</a> is to secure philanthropic support to advance the mission and strategic objectives of St. John’s Medical Center, including patient-centered care, clinical excellence, and community wellness.