1.   Bradley has a condition known as atrial fibrillation, which occasionally causes his heart to flutter to an irregular beat.

2.   A student can hear the thump of the beating heart or the irregular beat of a damaged heart.

3.   Heart specialists in Boston confirmed the irregular beat during an examination last week, calling the condition minor.

4.   The irregular beats continue whenever Horry exerts himself, but the pain has subsided.

5.   Doctors planned to give Tsibliyev an electrocardiogram Sunday to monitor his heart, which has recently registered an irregular beat.

6.   These devices sense irregular beats and re-establish rhythm by discharging small electric shocks to the heart muscle.