31.   It caused him, he claimed, to go to a hospital with a rapid heart beat.

32.   It is analogous to the way the human nervous system regulates breathing, heart beat and all the other functions necessary to sustain life.

33.   It the irregular heart beat gets too rapid, people feel discomfort in their chest.

34.   Mellman ruled out an irregular heart beat, but said further cardiac and neurological tests are scheduled.

35.   Pacemakers are devices that send electrical signals to heart muscles to maintain a normal rhythm of heart beats, and doctors have implanted them for nearly half a century.

36.   Reed showed the results by superimposing these ratings on the advertisement in a graphic display like the chart of a heart beat.

37.   Smoking also makes the heart beat faster and harder, and can damage arterial linings.

38.   The bottom one represents the force of blood in between heart beats.

39.   The display seemed aimed at demonstrating that Bradley, who occasionally suffers from an irregular heart beat, is in good shape.

40.   The heart beat accelerates and blood flow is diverted to the muscles and heart.