Chairman of Colchester Hospital Trust Richard Bourne was sacked on Friday
Health secretary Andy Burnham has called on health regulators to assess if any other hospitals require "immediate investigation".
The move comes amid concern that more care scandals could be discovered after the regulator, Monitor, took action against two foundation trusts in Essex.
"Patient safety is absolutely paramount and we must make sure that it takes precedence above all else," he said.
He said action was being taken but that more needed to be done.
On Friday, Monitor sacked the chairman of Colchester Hospital University NHS Foundation Trust, Richard Bourne, after finding it had consistently failed to improve waiting times.
Death rates among patients were also 12% higher than expected.
The sacking came less than 24 hours after the regulator highlighted major lapses in hygiene and unusually high death rates at nearby Basildon and Thurrock NHS Trust.
A task force has been sent in to force through improvements, in particular in the accident and emergency department.
Both Essex trusts have coveted foundation status, supposedly a marker of first-rate performance, which gives them greater freedom over how to manage finances.
Mr Burnham used his speech at the Royal College of Midwives on Friday to pledge tougher action, saying he had told the Care Quality Commission (CQC) to investigate if any other hospitals had similar issues.
"It has to be the highest priority for everyone at the Department of Health and in the NHS to ensure that the appropriate action is taken," he said.
Eleven NHS foundation hospitals are currently being scrutinised by Monitor for a "significant breach" of the terms relating to their foundation trust status.
The Patients Association said that people had been "appallingly" let down.
Director Katherine Murphy said: "How many times do the public need to keep hearing about this before the government is embarrassed enough to do something about it?
"The system of regulation and supervision needs to be urgently reformed."
Baroness Young, chairwoman of the CQC, admitted that the current inspection system - which the commission inherited from its predecessor - was flawed, but reforms would soon be in place.