MILL VALLEY (CBS SF) — A 72-year-old Bay Area runner finished a grueling 7.4 mile Marin County race despite suffering a heart attack while running.

Wolfgang Zech has run the Dipsea race 44-years in a row. It’s a torturous race that goes up and down trails, steep hills, and hundreds of steps from Mill Valley to Stinson Beach.

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During the event, Zech started having chest pains. Thinking he was suffering from heartburn, he continued onto the finish line.

“My body was not feeling too bad, except for the chest pain,” he said.

At the end of the race, Zech went to the emergency room, where doctors were shocked.

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“Everybody was sort of stunned. They were all in awe, shocked looking at this guy, not looking all that bad, telling him you just ran the Dipsea with a heart attack,” Zech said.

Doctors inserted two stents into a coronary artery that was 95-percent blocked.

Zech says he will be back next year to run his 45th Dipsea.

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Find more info on the Dipsea race here.