How did Elvis die? A look at the King of Rock 'n' Roll's 1977 death

The sad and shocking news of the death Thursday of Lisa Marie Presley after apparent cardiac arrest inspired many to research about the death of her father, the so-called King of Rock 'n' Roll, Elvis Presley.

Here's what to know about the King's 1977 death in Memphis.

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When and where did Elvis die?

Elvis was pronounced dead at Baptist Hospital on Union Avenue at 3:30 p.m. Aug. 16, 1977. He had been transported to the hospital by Fire Department ambulance after he was found on the floor of his upstairs bathroom at Graceland.

He reportedly had been in good spirits early that morning, and he had been scheduled to fly that night to Portland, Maine, to continue his 1977 concert tour. He was 42.

(The hospital was the same one in which Lisa Marie had been born, on Feb. 1, 1968; after being vacant for five years, the seven-story building was demolished in a controlled implosion on Nov. 6, 2005.)

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What did autopsy determine was Elvis' cause of death?

Dr. Jerry Francisco, the Shelby County Medical Examiner, who conducted an autopsy that day with a team of six pathologists, said on Aug. 16 that Elvis' death was due to cardiac arrest. (The family had a history of heart trouble: Gladys Presley, Elvis' mother, had died of a heart attack on Aug. 14, 1958, at 46.)

According to The Commercial Appeal, Francisco reported that Presley suffered from "mild hypertension" and "coronary disease that had gone undetected," and he "died in a matter of four short minutes of coronary arrhythmia, an irregular beating of the heart."

The newspaper reported that Francisco concluded that "there was no evidence of any drug use contributing to his death."

Did drug use contribute to Elvis' death?

Beginning shortly after Presley's death and continuing over the next several years, various investigations and reports began to attribute Elvis' cardiac arrest to "polypharmacy" (the simultaneous use of multiple drugs), which adversely affected what medical personnel variously referred to as Presley's "enlarged" heart, his "clogged" arteries and his "hypertensive heart disease."

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The Commercial Appeal reported that lab reports indicated that 14 drugs were found in Presley's blood at the time of his death, including "near toxic levels" of codeine, morphine, Placidyl and other prescription drugs. The "overdose of depressants" likely caused him to pass out in a slumped "fetal" position, and "he died when the drugs, in combination with pressure from his body weight, brought his respiration to a halt," according to the evening newspaper, the Memphis Press-Scimitar.

Presley's drug habit is now generally accepted as a cause of death. The Encyclopedia Britannica states, simply: "Elvis Presley died of a heart attack in 1977 brought on largely by drug abuse."