Haim's death was listed as "natural," the result of diffuse alveolar damage, which is a serious lung injury that can be caused by a number of factors. Pneumonia and hypertrophic cardiomyopathy (where the heart muscles become so strong they lower the heart's ability to pump blood) with coronary arteriosclerosis (where artery walls become thick) were also listed as the actor's cause of death.
Toxicology reports revealed there were no "significant contributing factors" in the actor's death on March 11 at the age of 38.
Haim had been suffering from pneumonia at the time of his death.
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