The family of Bill Paxton says the Titanic actor’s death a year ago following heart surgery was unnecessary and preventable, and has filed a wrongful death lawsuit against Cedars-Sinai Medical Center and the surgeon who operated on him.

Paxton, one of Hollywood’s most popular actors with such credits as Twister and Big Love, was 61 when he died following a stroke last February 25, 11 days after the heart surgery to replace an aortic valve and repair an aortic aneurysm.

In the suit filed Friday in Los Angeles Superior Court (read it here), Paxton’s widow, Louise Paxton, and their children James and Lydia claim Cedars-Sinai, Southbay Medical Partners and Dr. Ali Khoynezhad acted “negligently, carelessly, recklessly and unskillfully.” The surgical procedure is described variously in the lawsuit as “maverick,” “novel” and “unconventional.”

The surgery, Paxton’s family claims, contributed to the post-surgical complications that led to stroke and the actor’s death.

The suit further claims that Khoynezhad was “not in the hospital” as Paxton suffered complications, causing a delay in treatment.

“Bill Paxton and his family trusted the physicians and staff at this medical facility but instead Cedars-Sinai betrayed their trust,” said Paxton family attorney Bruce Broillet in a statement to press. “The surgeon’s actions resulted in this tragic and preventable death.” The statement says Khoynezhad left his position at Cedars-Sinai shortly after Paxton’s death.

In a press statement, the hospital said, “State and federal privacy laws prevent us from commenting about patient care without written authorization. But we can share the following: Nothing is more important to Cedars-Sinai than the health and safety of our patients. These remain our top priorities. One of the reasons for our high quality is that we thoroughly review concerns about any patient’s medical care. This process ensures that we can continue to provide the highest quality care.”