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Mary King

Mary Ann King

Mother, Grandmother, Farmville Fan and Cardiology Patient

St. Louis, Michigan

“All I wanted was a doctor I could trust to take good care of me. I found that in Dr. Diehl... I couldn’t ask for anything more.”

"With Dr. Diehl, I'm a patient, not a number."

When Mary Ann King moved to St. Louis, Michigan to live with her son, she left behind her daughter, her home of several decades and her long-time cardiologist.

Mary Ann suffers from chronic high blood pressure and atrial fibrillation, a common condition that occurs when the heart's two small upper chambers (the atria) quiver instead of beat regularly, allowing blood to pool inside and clot. While most people with this type of arrhythmia have nothing to worry about, Mary Ann’s condition requires regular monitoring and medical treatment.

“I’d lived in St. Joe all my life. I’d been with the same cardiologist for years and dearly loved him,” she said. “When you’re new to an area, you don’t know who’s good or who you’ll be comfortable with. 

However, a chance conversation at a dentist’s office changed everything. “She told me about Dr. Rodney Diehl, a new interventional cardiologist in Alma, and gave me his number,” Mary Ann said. “That was six months ago and I am so glad I found him. He’s great! From the first time I met with him I felt confident that he was going to take good care of me.” 

Mary Ann said Dr. Diehl shows genuine concern for his patients. “I don’t feel like I am a number to him,” she said. The caring attitude is reflected in his support team as well. “He has great people on his staff – personable and on the ball. They make you feel comfortable and welcome and they are very good about staying in touch. It makes all the difference in the world that they are kind.”

For more than 20 years, Mary Ann worked as a “jill-of-all-trades” for a small company that custom manufactured jackets for boilers. “I did everything from accounts payable to inventory control,” she said. Like her, Mary Ann said that Dr. Diehl knows when to conserve resources and time. “Some doctors are all tests, tests, tests,” she said. “Dr. Diehl isn’t like that. He is extremely thorough, and instead of simply ordering new tests, he reviewed the results of the tests I’d had done with the other doctors. He told me to pay attention and, if I felt something that was troubling or new, to call him.”

Arthritis in her back has changed the way Mary Ann gets around – she uses an electric cart for shopping – but her health issues haven’t stopped her. “I have an enclosed ‘wagon’ hitched to the back of my car,” she said. “I can get the cart into the wagon by myself so I get around on my own.” Being independently mobile allows her to manage her own health care. “Right now, I see Dr. Diehl every month or so, but we are moving toward checking in once every three months.” 

While moving to new city at age 69 was stressful, Mary Ann said finding her new cardiologist was a relief. “All I wanted was a doctor I could trust to take good care of me,” she said. “I found that in Dr. Diehl. He knows what he’s doing and treats me as a friend. I couldn’t ask for anything more.”



Dr. Diehl sees patients at 200 E. Warwick Drive in Alma, and at MidMichigan Health Park–Mt. Pleasant, 4851 E. Pickard Street. Appointments may be made with or without a physician referral by calling his office toll-free at (855) 289-5353. Those who would like more information about Dr. Diehl may visit or call MidMichigan Health Line toll free at (800) 999-3199.