Though stroke deaths in the U.S. have fallen sharply in recent decades, research now shows that the long decline in mortality from "brain attacks" has leveled off — and doctors are concerned.

"We are in trouble," Dr. Janet Wright, executive director of the Million Hearts program at the Centers for Disease Control and Prevention in Atlanta, told NBC News MACH in an email. "Not only are we seeing a plateau, a stalling of the decades-long decline in death rates from stroke, but now strokes are occurring in younger people, those 35-64."

Wright said the leveling off was likely attributable to high rates of diabetes, obesity and physical inactivity — a "deadly trio" of risk factors for stroke, which occurs when a clot blocks the flow of blood to the brain or a blood vessel in the brain bursts.

What can be done to reduce the prevalence of these risk factors? Are there new drugs in the pipeline that can help prevent stroke — and save the lives of stroke patients? What about new surgical interventions?

Four prominent stroke experts tackled these and other questions in a one-hour panel discussion held Monday at Harvard T.H. Chan School of Public Health in Boston. You can watch the event, entitled Stroke: Successes and Setbacks with a Notorious Silent Killer, right here.

The panelists were Dr. Wright; Dr. Umberto Campia, a cardiologist and vascular medicine specialist at Brigham and Women's Hospital; Dr. Gokhan Hotamisligil, chair of the department of genetics and complex diseases at the Harvard T.H. Chan School of Public Health; and Dr. Walter Koroshetz, director of the National Institute of Neurological Disorders and Stroke.

The discussion was moderated by MACH's editorial director, David Freeman, who has also moderated panels on self-driving cars, gene editing and federal funding of biomedical research.

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