Lisa Marie Presley died in January from a small bowel obstruction that was caused by adhesions, or scar tissue, that developed after she had bariatric surgery years ago.

The official autopsy report, obtained by CNN, also stated that there was no evidence of injury or foul play. The manner of death was deemed natural.

Dr. Michael Camilleri, a consultant and professor in the Division of Gastroenterology and Hepatology at the Mayo Clinic, said that the medications found in Presley’s system may have slowed down the motility of her intestine and made it more likely for it to get obstructed by the adhesions.

However, he added that adhesions can happen to anyone and that the medications found in Presley’s system did not necessarily mean that she was more prone to develop complications.

Dr. Folasade P. May, associate professor of medicine at the David Geffen School of Medicine at UCLA and director of the Melvin and Bren Simon Gastroenterology Quality Improvement Program, said that she suspects Presley developed a cardiac arrest because she had a severe complication from the small bowel obstruction.

Presley was 54 years old. She is survived by her four children.

Her last public appearance was at the Golden Globe Awards just days before her death. She attended the awards show with her mother, Priscilla Presley, to support the Baz Luhrmann film “Elvis,” about her late father.