Emotional intelligence is the ability of a person to identify their emotions and then manage and regulate their emotions. EI also includes being able to identify the emotions of others and manage interactions with them based on the emotions they identified. You can know if you have EI when you are able to pick up on your emotions and realize how they are affecting your actions and managing your actions after picking up on the emotion. I think EI Isaac important ability to have as it can improve your relationships with other people and yourself.
EI is an important consideration in marketing because it allows a company the ability and knowledge of knowing who their customers are, what they feel, their interest, etc. Knowing the mood and feelings of the type of customer a company is trying to attract will allow them to better target their marketing approach.
In the case of medical devices I believe EI would benefit in sales and marketing by being able to empathize with their target customer and advertising to the customer in a way that shows the company is sensitive to and understands what the customer is dealing with.