Lisa Marie Presley's cause of death was revealed to be a small bowel obstruction due to bariatric surgery she had years ago, an autopsy report showed.
The 54-year-old, who was the only child of the late singer Elvis Presley, had complained of abdominal pain the morning of her death in January and was eventually found unresponsive in her home, according to the report released Thursday and viewed by ABC News.
The obstruction was caused by adhesions, or bands of scar tissue that form between organs in the abdomen, mainly the small intestine, after surgery according to the Cleveland Clinic.
MORE: Settlement reached after dispute over Lisa Marie Presley's estateExperts said that while small bowel obstructions are common complications of any abdominal surgery -- including weight-loss surgery -- it's uncommon for them to not be caught and treated.
"It's very rare for a small bowel obstruction to be a very rapid process, that a person can be totally normal, and then they can be super sick and die from the obstruction itself," Dr. Vivek Prachand, a professor of surgery at University of Chicago Medicine who was not involved in Presley's case, told ABC News.
Bariatric surgery is often performed when diet and exercise have not worked to lose weight, according to the Mayo Clinic. The most common type of surgery is a sleeve gastrectomy, which involves removing about 80% of the stomach.
The other two types of surgery -- gastric bypass and biliopancreatic diversion with duodenal switch -- involve rerouting the small intestine.
The autopsy report did not reveal which type of surgery Presley had performed, but Dr. Seth Kipnis, director of bariatric and robotic surgery at Jersey Shore University Medical Center, said the latter two are the most common when it comes to the risk of a small bowel obstruction.
However, small bowel obstructions are a risk of any type of abdominal surgery, not just weight-loss surgeries.
"Small bowel obstructions are very, very common from any previous abdominal surgery from having your appendix removed, colon surgery," Kipnis, who was not involved in Presley's care, told ABC News. "A hysterectomy or C-sections all have risks of blockages from scar tissue."
The doctors said that, typically, when someone has a small bowel obstruction, they experience symptoms including not having any bowel movements or vomiting from not being able to keep food or liquids downs.
MORE: Priscilla Presley shares photo with all 3 of her granddaughters"So, after 12 to 24 hours of not being able to keep something down, they often are becoming dehydrated, and are best treated by an emergency room where a CT scan of their abdomen, pelvis would reveal that this is the cause of their severe nausea and vomiting," Kipnis said.
For patients that have undergone abdominal surgery, scar tissue can form and lead to a bowel obstruction. However, it doesn't necessarily need to be treated with surgery.
"You can frequently treat them by decompressing the stomach and observing the patient and making sure that they're getting better rather than worse, if they're in a monitored setting, in a hospital and so forth," Prachand said. "But, if the pain is getting worse, or there's concern that there might be obstruction has led to reduction of blood flow to parts of the intestine, then the patient needs an emergency surgery."
While bariatric surgery comes with risks like any other operation, the doctors say that stories about complications following the surgery might make people believe it's not safe.
Evidence shows the contrary. The risk of death linked to bariatric surgery is about 0.1% and the risk of major complications is about 4%, according to the American Society for Metabolic and Bariatric Surgery.
Additionally, UCLA Health says the risk of dying within 30 days of bariatric surgery is much lower than other surgeries including gallbladder surgery and hip replacement surgery.
The risk is also lower when done with minimal invasion or laparoscopically. The doctors add that, in the long-term, the risks from complications due to obesity are far greater than complications from weight-loss surgery.
"I think that these perceptions of risk dissuade people who might potentially benefit from having these operations," Prachand said. "I do these operations, and so you could certainly make the case that I have a bias here…but we've had more patients end up passing away due to complications related to the medical problems that they have that are obesity-related, while waiting to undergo surgery than those who have had the operation."