With the first ribs fixed by neck muscles (scalene muscles and sternocleidomastoid muscle), the intercostals muscles (especially external intercostal muscles and interchondral part of internal intercostal muscles of opposite side), elevate the 2nd to 12th ribs and thus act as inspiratory muscles.
Medical Dictionary. arrhythmia. play. noun arÂ·rhythÂ·mia \Ä-Ërith-mÄ-É\. Medical Definition of arrhythmia. : an alteration in rhythm of the heartbeat either in time or force.
An arrhythmia is an abnormality in the timing or pattern of the heartbeat. When you have an arrhythmia, your heart may beat too quickly or too slowly, or you may experience an irregular rhythm in which your heart feels as if it is skipping a beat.. Some types of arrhythmia may not be serious.