An alleged murder victim was found with a stab wound to the chest after emergency services responded to a 999 call, a court heard on Tuesday.
Barry Dixon was taken from a house in Perth to Ninewells Hospital, in Dundee, where a scan revealed he had fluid in the sac around his heart.
Blood gathered around the organ was removed but a single stab injury to the heart was identified, the High Court in Edinburgh was told in agreed evidence.
But during efforts by surgeons to repair the injury Mr Dixon went into cardiac arrest and was later pronounced dead.
The court heard that police and paramedics had attended at the property at Wallace Court, in Perth, following an emergency call. Mr Dixon was found lying on a mattress with a visible chest wound.
Robbie Smullen (23) has denied assaulting Mr Dixon by striking him on the body with a knife or similar instrument and murdering him at 25 Wallace Court on June 4 in 2019.
Smullen has also denied assaulting Paul Booth at Nimmo Avenue, in Perth, on June 3 in 2019 by challenging him to fight, chasing him, fighting with him, threatening him and repeatedly punching him on the head.
He has lodged special defences of self defence to both of the charges.
Smullen faces a further charge of failing to comply with a bail condition on June 3 and 4 in 2019 that he remain within 25 Wallace Court between 7 pm and 7 am.
His mother Mary Theressa Smullen (46) is accused of attempting to pervert the course of justice on various occasions on June 4 in 2019 at 25 Wallace Court, 92 Craigie Place and Perth Police station, all in Perth.
It is alleged that knowing her son had stabbed Mr Dixon she pretended to police that the crime had been committed by Shannon Beattie.
Jordan Walker (24) said Mr Booth visited his home in Nimmo Avenue on June 3 in 2019. He said Mr Booth was drinking and he and Mr Booth smoked cannabis.He said Smullen, who was also a friend, arrived and had been drinking.
In a statement to police he described Smullen as "pretty intoxicated" and "wasted".
He agreed that when he told the police that he later found Smullen and Mr Booth fighting and that he tried to split it up he was telling the truth.
The trial before Lady Carmichael continues.
