What Was Stan Lee's Cause of Death?

ExtraTV reported that more details have been revealed about Stan Lee's death. TMZ received a copy of Lee's death certificate, which states that Lee's immediate cause of death was cardiac arrest, as a result of respiratory and heart failure. Aspiration pneumonia was also listed as a contributing factor in his death. Earlier this year, Lee had been rushed to a hospital after experiencing shortness of breath and an irregular heartbeat.