Medical Crisis: Bobbi Kristina Brown's Aunt Tina Brown In Surgery For 'Vascular Blockages'

Bobbi Kristina Brown's aunt Tina Brown is undergoing surgery Wednesday to clear vascular blockages that sent her to an Atlanta hospital Sunday, RadarOnline.com has exclusively learned.

Tina, the sister of singer Bobby Brown, was rushed to a hospital emergency room Sunday evening because of numbness in her right side, as RadarOnline.com previously reported.

Doctors found "vascular blockages in her neck" and an irregular heartbeat, her representative said She could remain hospitalized for another week, depending on the success of Wednesday's procedure.

Tina is "just overwhelmed" by the stress of her niece's medical crisis, the rep said. She has suffered several heart attacks in the past and has a pacemaker.

Tina has been in Atlanta since soon after her niece was hospitalized on January 31, holding vigil with other family members and praying for the 21-year-old Bobbi's recovery.

Before her own hospitalization, she was involved in an argument at an Atlanta hotel while celebrating Bobby Brown's 46th birthday on February 5 in which she hit her son Shayne on the head with a glass. He declined to press charges against his mother.

Tina was close to her sister-in-law Whitney Houston and revealed they had smoked crack together in an interview with The National ENQUIRER in 2006.