Cosmetic surgeon Dr. Amiya Prased said patients must tell doctors about pre-existing conditions before surgery.
"The patient needs to be up front with us about all their medical conditions, because they can have bleeding, they can have cardiac problems, they can have drug interactions during surgery as well as after," Prased said.
A scholar for more than 30 years, West left her job as university professor to manage her son's career, and in the past year she worked as head of the Kanye West Foundation, which is aimed at keeping inner-city youth in school.
The strong bond shared by West and her son was undeniable. Kanye has made references to his mother on all of his albums.
Most recently, West was the inspiration for "Hey Mama," on Kanye's hit album "Late Registration."
"Hey Mama, I wanna scream so loud for you, cuz I'm so proud of you," writes Kanye. "I appreciate what you allowed for me. I just want you to be proud of me."
In her book "Raising Kanye" West shared the struggles she faced as a single mother.
"It was a challenge. But when you have challenges that's what makes life worth living, right? Kanye was a great kid," she said.
The hip-hop star's Web site has been flooded with fans expressing their condolences.
Kanye is asking for privacy, but the family did release a statement thanking everyone for their support.
ABC News' Jesus Ayala contributed to this report.