Disgraced publicist Max Clifford had complained about unheated prison cells and cold showers "every day" before his death, an inquest has heard.
Clifford, 74, was serving eight years for sex offences when he collapsed at HMP Littlehey in Cambridgeshire.
The PR guru's daughter Louise told a hearing conditions at the prison "had an influence on his deterioration".
Cambridgeshire assistant coroner Simon Milburn said a cardiologist would be asked to consider if this was the case.
Clifford, from Hersham in Surrey, died of congestive heart failure on 10 December 2017, two days after his collapse, the hearing at Huntingdon Law Courts was told.
Letters to the prison governor from her father's doctor and barrister received "no response" while her father "was fading fast", Ms Clifford said.
The pre-inquest review hearing was told consultant cardiologist Prof Jon Townend had provided an expert review of Clifford's heart failure.
This confirmed he had cardiac AL amyloidosis, a "rare", serious condition caused by a build-up of abnormal proteins in organs and tissues.
A date for the full inquest has yet to be set.
During his 50-year career as a publicist, Clifford looked after press and publicity for a mix of clients including Marlon Brando, Marvin Gaye, Muhammad Ali and Jade Goody.
In 2014, he was investigated as part of Operation Yewtree, and eventually jailed after being convicted of eight indecent assaults on women and young girls.
Clifford continued to protest his innocence, and an appeal against his sentence was due in 2018.