Dennis Atherton, a cardiac sonographer at Maine Medical Center, prepares to check on a mechanical heart valve that was implanted last year in Mason Lee, 8, of Winslow, during a routine checkup in Portland. Mason initially had a valve placed in his heart at birth, but had it replaced when he outgrew it.
Mason watches a Boston Red Sox game on television with his father Jamie and sister Hunter.
Mason points to his forehead while playing in the front yard at his Winslow home to show where a bruise will start to form after he got hit while playing with his sister. Because of a mechanical valve implanted in his heart, he must take Coumadin, a blood thinning medication, which causes him to bruise easily.
Hillary Lee and her daughter watch as cardiac stenographer Dennis Atherton performs a checkup on Mason. Mason initially had a valve placed in his heart when he was 6 weeks old.
A check on the mechanical valve placed in Mason's heart is shown on a video monitor during his checkup at Maine Medical Center.
Pictured at left is the St. Jude Medical Masters HP Series 15mm mechanical heart valve in comparison to an adult-sized mechanical heart valve. The half-inch St. Jude valve was inserted into Mason's heart when he was 5 weeks old and lasted about seven years before he had it replaced in 2014.
Mason and his friends enjoyed a pizza party celebrating the end of basketball season. Because of a mechanical valve implanted in his heart, Mason can only play non-contact sports. He tried out for baseball on the same day of the pizza party.
Mason, with a baseball in hand, looks out the window toward the backyard as his father takes the cover off the grill before dinner.
Mason and Hunter play inside their Winslow home.
Mason buries his head in his hands and leans against his mother after over-exerting himself playing with his sister at their Winslow home.
Mason listens to his coach while he and many other boys try out for a youth league baseball team.
Mason recoils in reaction to a playful punch from his sister in the living room of their home. Because of medication he takes, Mason bruises easily.
Mason rubs his eyes as he begins to get tired while playing hide and seek with his sister.
Mason is chased up the stairs by his mother Hillary at bedtime.
Mason reads in bed before going to sleep.
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