Body has a natural resparative process for healing wounds. Generally wounds take about 6-8 weeks to heal completely. Bones may take a little longer. The new tissues will need some time to get used to the stress and strain of activities of daily life. This process is called the remodeling. It is natural to experience some discomfort during healing and remodeling stages.
The surgical wounds are stitched using special needles and suturing threads. Some materials are bio-degradable or self absorbing. They need not be removed. Some need to be removed after the necessary period (like silk and nylon).
Generally all the wounds of heart operation are repaired using self absorbing stitch materials. These can not be seen outside and need not be removed. Small wounds are sometimes repaired using silk or nylon sutures. These are usually removed just before discharge.
