Shehata is a cardiac electrophysiologist, a doctor who specializes in diagnosing and treating problems with the heart’s electrical system. He has experience with a broad spectrum of heart rhythm disorders and also cares for people with heart failure and survivors of cardiac arrest.

“Over the past two decades, Dr. Shehata has emerged as a nationally recognized cardiac electrophysiologist and academic leader,” said Susan Cheng, MD, MMSc, MPH, chair of the Department of Cardiology in the Smidt Heart Institute. “His leadership will mean continued progress in this important field.”

As a researcher, Shehata has led groundbreaking clinical trials for new types of pacemakers and other technologies for treating heart rhythm disorders. He also studies ways that AI can be used to personalize care.

Shehata’s most recent research includes a trial of a new treatment for atrial fibrillation, which occurs when the upper chambers of the heart beat out of sync with the lower chambers of the heart. The treatment, pulsed field ablation, targets heart cells involved in an abnormal heart rhythm. The U.S. Food and Drug Administration approved several pulsed field ablation systems, including one studied by Shehata and other researchers, in 2024.

Shehata and colleagues have also studied leadless pacemakers, miniature devices that attach to the heart muscle and that, unlike traditional pacemakers, don’t require a battery and wires.

As division director, Shehata will oversee a program that provides research-backed care and trains new heart rhythm specialists. The program offers a two-year fellowship to medical school graduates seeking advanced knowledge and skills in electrophysiology.

“Through his leadership of the Interventional Electrophysiology Laboratory and the Clinical Cardiac Electrophysiology Fellowship Program, Dr. Shehata has expanded access to advanced therapies and enhanced the training of future electrophysiologists,” said Eduardo Marbán, MD, PhD, executive director of the Smidt Heart Institute and the Mark S. Siegel Family Foundation Distinguished Professor.

Shehata earned his medical degree from the University of California, San Diego, School of Medicine. He completed internal medicine residency training at UCLA and his cardiology fellowship training at Cedars-Sinai, where he was chief fellow. He also completed advanced fellowship training in cardiac electrophysiology at Cedars-Sinai. He served as faculty at UCLA before being recruited to join the cardiology faculty at Cedars-Sinai, where he is a professor of Cardiology.

U.S. News & World Report rates the Smidt Heart Institute a top 10 cardiovascular center in the U.S. and #1 in California.

Read more from Cedars-Sinai Stories and Insights: New AFib Treatment Helps Dad Regain His Heart Rhythm

The 52-year-old has always enjoyed a high-energy lifestyle, managing the intensity of producing films and television shows (Ladder 49, Flight Plan, Top Gear, Wheeler Dealers) by eating healthy, running and biking along the Los Angeles River. After his daughter was born in 2020, Nieminen assumed his constant exhaustion was the typical kind that comes with sleepless nights caring for a newborn. Still, he and his wife, Kaisa, found it odd that picking up his daughter left him depleted.

“My battery was constantly drained,” Nieminen said. “Being physically active all my life, it was quite alarming. Deteriorating this quickly when I’m just over 50 seemed sort of dramatic.”

Nieminen also noticed his heart seemed to beat too fast at times and occasionally it would skip a beat, so in 2023 he made an appointment with Cedars-Sinai cardiologist Ronit Zadikany, MD. Zadikany diagnosed him with atrial fibrillation, an irregular heart rhythm that occurs when the upper and lower chambers of the heart beat out of sync. The condition tends to worsen with time and can cause the heart to beat too slowly, too quickly or irregularly, impeding blood flow. Common symptoms include fatigue, heart palpitations, dizziness and reduced stamina. Left untreated, atrial fibrillation can cause a slew of cardiovascular complications—including stroke.

Nieminen’s cardiologist referred him to Christine M. Albert, MD, MPH, an expert in atrial fibrillation and chair of the Department of Cardiology in the Smidt Heart Institute. Albert recommended cardioversion, a procedure commonly used to reset the heart to a normal rhythm. The results made Nieminen feel like himself again, but only for a day. A second cardioversion combined with a medication known to work for many people also had temporary effects.

Albert was determined to find Nieminen a treatment that would have long-term results. She suggested he might benefit from catheter ablation, a procedure that destroys cells and creates a small scar within the heart, breaking up or insulating the electrical signals causing the heart to beat out of sync. She connected him with Michael Shehata, MD, a cardiac electrophysiologist in the Smidt Heart Institute.

Shehata was leading a clinical trial investigating a new catheter ablation called pulsed field ablation. Rather than create scars, pulsed field ablation targets heart cells involved in an abnormal heart rhythm.

Nieminen underwent the procedure in January 2024.

“When other options fail, this procedure can be life-changing for patients,” Shehata said.

Pulsed field ablation is done by threading a catheter through a vein in a patient’s leg until it reaches the top chambers of the heart. Once in place, a cardiologist sends a high-voltage electrical impulse through the catheter. The energy penetrates cell walls and destroys specific heart cells, preventing abnormal signals from causing an irregular heartbeat. The procedure takes 30 to 60 minutes.

“The energy is delivered specifically to heart cells without injuring nerve cells, smooth muscle cells, or other, healthy cells,” said Shehata, who is also director of the Interventional Electrophysiology Laboratory at the Smidt Heart Institute. “For some patients with atrial fibrillation, this procedure may be safer than conventional ablation procedures that destroy small areas of heart tissue.”

Following U.S. Food and Drug Administration approval of several pulsed field ablation systems, the procedure is now available for use outside of a clinical trial.

Advances in treatment couldn’t come at a better time. Atrial fibrillation is the most common type of irregular heartbeat and deaths related to the condition have been increasing for more than two decades, according to the U.S. Centers for Disease Control and Prevention.

Today, Nieminen is back to long runs and cycling through his neighborhood. He also works with local organizations to advocate for safe walking and biking paths in Los Angeles. Most importantly, he can now lift his daughter into the air like the high-energy dad he is.

A device that was implanted to record Nieminen’s heart rhythm shows proof of his progress: He has been free from atrial fibrillation since getting pulsed field ablation.

“Don’t hesitate to share with your doctors when something feels off because you feel like you’re being a hypochondriac or you think it’s too insignificant to bring up,” he said. “As you get older, it’s especially important to listen to your body, eat right and stay active, and that doesn’t necessarily mean doing a 10K. Everything your mom would tell you growing up: Stay active, eat healthy, get sleep and get checkups with your doctor. Mom knew what she was talking about.”

Read more on Cedars-Sinai Stories and Insights: Back Into Rhythm | Adjusting to an AFib Diagnosis

Shehata told HealthCentral that with AFib, the heart races in a disorganized, chaotic rhythm and that atrial flutter is a similar but less common condition also affecting the atria, or upper chambers of the heart.  

“Atrial flutter is a regular circuit within the atria,” said Shehata, who also is director of the Clinical Cardiac Electrophysiology Fellowship Training Program in the Smidt Heart Institute. “That means there’s an area of the upper chamber where the tissue stretches or scars in such a way that it forms a very organized electrical path. It overdrives your natural heart rhythm.”

He said it is possible to have both AFib and atrial flutter, which can lead to blood clots and stroke if left untreated. 

“One isn’t worse than the other,” Shehata told HealthCentral. “They’re both dangerous.”

While medications are available to help control AFib and atrial flutter, Shehata recommended eating healthy meals and getting regular exercise as another approach.

“We always encourage patients to do their part and modify their lifestyle to prevent arrhythmias from coming back,” Shehata said.

Shehata told HealthCentral that getting a good night’s sleep is another way to avoid triggering an arrhythmia. But he noted that AFib can disrupt sleep, worsening the condition. 

“Those nighttime episodes can wake people up out of a sound sleep and keep them from sleeping well,” he said. “It’s a vicious cycle.”

Click here and here to read the complete articles from HealthCentral.