This clinical trial studies the effects of botulinum toxin injections in preventing abnormal scarring after sternotomy surgery (an operation where the breastbone is cut to access the heart). The study compares Botox injections to sodium chloride solution (placebo) when administered immediately after surgery. The purpose is to evaluate whether botulinum toxin can improve the appearance of surgical scars.

During the study, patients who undergo sternotomy will receive injections along their surgical wound. One half of the surgical scar will be treated with Botox, while the other half will receive placebo. Both substances will be administered through intradermal injection (injection into the skin). The treatment involves a single injection session performed shortly after the surgery.

The appearance of the surgical scar will be evaluated over time by skin specialists who will not know which part of the scar received which treatment. These evaluations will continue for up to 18 months after surgery to determine if there are differences between the Botox-treated and placebo-treated areas of the scar. The study will assess various aspects of scar healing, including the scar’s width and overall appearance.