A children's heart surgery centre that was temporarily closed last year due to fears over mortality rates is safe, according to a comprehensive review of its services.

But the report into paediatric cardiology at Leeds General Infirmary (LGI) outlined the experiences of 16 families who complained of poor care at the unit, prompting apologies from b oth NHS England and the Leeds Teaching Hospitals NHS Trust, which runs the hospital.

One mother described how she felt pressurised into having an abortion, which was against her Muslim beliefs.

Others complained about a lack of compassion following the death of their child.

NHS England said in its overview of the report: "We conclude that these families did not get the level of care or service that they deserved and for this we are truly sorry."

Operations at the LGI unit were suspended for more than a week last year after NHS England raised concerns about data on death rates at the centre.

The move provoked huge anger and debate, especially as parents and clinicians from the unit linked it to the ongoing controversy about which children's heart surgery units were to be closed as part of a nationwide rationalisation of the service.

Surgery resumed on April 10 last year and NHS England announced it was implementing the full review that reported.

The report was in two parts.

The first was a statistical analysis of mortality rates, focussing on the 35 children who died following surgery at the unit from 2009 to March last year.

A second part of the report examined the experiences of 16 families who felt they had been let down by the unit, prompting six to have their child's treatment transferred to another centre.

One parent told the investigators: "We were given no support by the staff after Annie died.

"We were given a leaflet.

"Nobody asked how we were getting home in the early hours of the morning."

Another described how a book had gone missing in which their son had been writing about his experiences before his death.

"It was like losing another part of him," the parent said.

"We asked the staff to find it.

"They told us they could not find it.

"They didn't seem bothered.

"They didn't seem to realise what it meant to us.

"We had been going to Leeds for 10 years and no-one has rung to see how we are."

The LGI unit had been earmarked for closure, along with two others in Leicester and the Royal Brompton in west London as part of a nationwide plan to streamline children's cardiac surgery into fewer, more specialised units.

But, after a fierce campaign by some parents whose children were treated at the LGI and two legal challenges, Health Secretary Jeremy Hunt halted the plan and ordered NHS England to re-evaluate the whole process.

Dr Yvette Oade, the chief medical officer at Leeds Teaching Hospitals, said: " We are pleased for our patients, families and staff that the Mortality Case Review has confirmed the medical and surgical care provided by the children's heart surgery unit in Leeds is safe.

"We are very sorry however that the 16 families who shared their stories with the Family Experience Review felt we did not provide the care they had a right to expect.

"We sincerely apologise to those families and will, of course, ensure we learn from what they had to say and improve our services as a result of this."

NHS England's deputy medical director Dr Mike Bewick said: " I am happy to say, on the basis of the evidence we currently have, that services in Leeds are safe and are running well."

Dr Bewick thanked the 16 families whose experiences were outlined in the review.

He said: "Such experiences cannot be defended and I would look to the trust to respond positively to this report."

Parents who have campaigned to save the Leeds unit welcomed the conclusion the centre was "safe".

Sharon Cheng, the director of the Children's Heart Surgery Fund, said: " Leeds' outcomes and quality of care are in line with national requirements and those of other units, and parents can feel 100% reassured in the treatment that their children will receive at Leeds."

Mrs Cheng said: " While one complaint is too many, the vast majority of families and patients under Leeds' care tell us on a daily basis what a superb service they receive from Leeds and that they feel the team has gone above and beyond to care for their children."

But the group Fragile Hearts, which represents parents who have lost their children or seen them suffer medical harm as a result of their heart surgery, said today's report "is evidence that the culture which exists at LGI heart unit takes no account of the emotional, psychological or spiritual needs of children or parents".

In a statement, Fragile Hearts said: " We do not believe that the changes instigated by NHS England within the unit go far enough as we believe that the changes required are not only in the skill and care provided but in the attitude of those care providers.

"We therefore call for systemic changes within the unit, but above all we hope that nobody else ever has to walk in our shoes."

It said: " It is our belief that the data provided for the mortality review is flawed and we call for access to the data by an independent body; a public review of this data and, indeed, the process followed when a unit fails to meet these targets."

Anne Keatley-Clarke, chief executive of the Children's Heart Federation, welcomed "the report's recommendations that address the unacceptable care received by the families".

But she added she was "concerned that issues we raised with the CQC back in 2011 have been totally missed".

"These include the quality of heart surgery and repeat operations, along with the morbidities of children who had received treatment at Leeds General Infirmary," she said.

"We look forward to seeing the third strand of the review which investigates concerns that have been raised by other clinicians in relation to inter-unit transfers and patient pathways and hopes that the future report will address our concerns."

Pudsey Conservative MP Stuart Andrew, who has campaigned to keep the unit open, said: " It is extremely good news that the unit has been found safe and shows that the heart unit in Leeds is delivering a level of service that is comparable to others in England just as we thought.

"It is important to recognise that a small number of families had an experience at the unit that was below an acceptable standard. I know from my own experience of the unit that the staff there will be deeply saddened by this but will also be more determined to keep striving to provide the best possible service.

"The unit now has four permanent, full-time surgeons and is currently being led by a world-class surgeon and overwhelmingly, the number of people who have been treated at the unit have had a positive experience of professional care and medical expertise.

"I know that those running and working in the unit will embrace these findings and to learn lessons from those experiences and improve the service and I also hope that NHS England will also learn lessons from this experience and in future only take drastic action if the information it is based on is relevant and valid.

"Of course it is vital to ensure patient safety but it is equally vital that people going through a highly stressful and emotional time are not frightened unnecessarily."

Sir Roger Boyle was head of the National Institute for Cardiovascular Outcomes Research (Nicor) when it raised concerns about outcomes at Leeds last year, and later said he would still not send his daughter for treatment there.

He told BBC Radio 4's Today programme the behaviour of MPs who campaigned to keep the unit had been "downright disgraceful".

Sir Roger said: "The principles that I was fighting for remain absolutely the same.

"I wanted to minimise risk to these very sick children and make sure that they were cared for in an atmosphere that was caring and compassionate.

"That's what the safe and sustainable programme was aiming to deliver."

Sir Roger insisted there had been an "overwhelming consensus" in about 2006 that the NHS needed fewer larger child surgical centres that could provide a "comprehensive and safe service".

He said he still believed there were too many such units, adding: "That principle I think is still adhered to by many but it looks as if the establishment has turned their face against it, largely I think influenced by the strength of views of families who have had good outcomes in each of these centres... but also through political intervention.

"The behaviour of some of the MPs was downright disgraceful.

"Particularly some of the West Yorkshire MPs vying for position to be the MP who saved the Leeds surgical programme."

Michelle Elliott said the unit had been treating her daughter Jessica for 11 years, and two years ago said she needed a transplant.

"My issue was that it took seven months to get her to the transplant centre, by which time they told us it was almost too late," she told BBC Radio 4's Today programme.

"We got there on April 2 for what we thought was a second opinion, only to be taken to the small room to be told that actually you are not here for a second opinion, she is very sick and she needs a transplant straight away."

She received her new heart 27 days later, but in the meantime she had a stroke.

It is the stroke now that is impacting on Jessica's life, not the heart.

Ms Elliott said: "Our argument is that those seven months were wasted, and we could have got her there sooner if I had not been blocked in asking for her to go...

"From the heart point of view she is doing brilliantly well, but from the stroke point of view she is still not back in mainstream school and she is still using a wheelchair. But her mind is there.

"We are the lucky ones. There are many parents in the group whose babies and children have died.

"We want to work now with the trust to make sure other families do not suffer in the way that our family have suffered."

Ms Elliott added: "The mortality report says yes, it is safe, but it is not a clean bill of health. There were numerous recommendations made for the heart unit that they have to fulfil over the coming months."