Talk to General Physician on Cardiology

my father is a bladder cancer survivor done with radiation and chemo last year in September 2020. he is a cardiac patient ,sugar patient and had fits history too for which he take epival tablets since 2013. last year he had covid and after that had minor heart attack too . Dr told us that water started accumulating in his body caused pressure on his heart which caused him heart attack. nowadays he is again feeling pressure on heart and pain in chest for which he consulted Dr and he advices thallium . attached is the report can any cardiologist plz interpret itt and tell me about it . p.s. he had a major attack in 1999 angiography and angioplasty done . another in 2008 again done with angiography and angioplasty and last attack last year for which only medicines were prescribed