Michael Madsen's manager previously said, 'What we understand is Michael had a cardiac arrest and was found unresponsive in his Malibu home' on July 3. The 'Kill Bill' actor was 67.

Less than a week after acclaimed actor Michael Madsen was found dead in his Malibu home, an official cause of death has been revealed. Madsen passed away at 67 from heart failure, his cardiologist told NBC Los Angeles.

Madsen died from cardiac arrest, his manager Ron Smith told NBC News. Cardiac arrest occurs when the heart stops functioning. It can lead to death without immediate treatment, according to Mayo Clinic.