context: Tito became increasingly ill over the course of 1979. During this time Vila Srna was built for his use near Morović in the event of his recovery. On 7 January and again on 11 January 1980, Tito was admitted to the Medical Centre in Ljubljana, the capital city of the SR Slovenia, with circulation problems in his legs. His left leg was amputated soon afterward due to arterial blockages and he died of gangrene at the Medical Centre Ljubljana on 4 May 1980 at 15:05, three days short of his 88th birthday. His funeral drew many world statesmen. Based on the number of attending politicians and state delegations, at the time it was the largest state funeral in history; this concentration of dignitaries would be unmatched until the funeral of Pope John Paul II in 2005 and the memorial service of Nelson Mandela in 2013. Those who attended included four kings, 31 presidents, six princes, 22 prime ministers and 47 ministers of foreign affairs. They came from both sides of the Cold War, from 128 different countries out of 154 UN members at the time.
question: టిటో యొక్క మరణం కారణం ఏమిటి?
answers: gangrene