Botulinum Toxin Injection After Sternotomies to Improve Scar Aspect and Impact

"Intervention will be made immediately after surgery, still under general anesthesia, by the cardiac surgeon, after suture.~Each patient will receive (either in the lower part or the upper part of the scar according to randomization) 50 international units (IU) of type A botulinum toxin (Botox®, Allergan aesthetics) diluted in 1 mL of saline to enable injection of 5 IU at each point, every centimeter, at 1 cm of each scar side.~An equivalent volume of saline will be injected under the same modalities in the other part of the scar."