It still isn't known for sure whether this approach is beneficial, harmful, or has no effect at all.
Professor Stewart, who works between the Auckland City Hospital, Green Lane Cardiovascular Research Unit and Auckland Heart Group, estimated about 13,000 patients are admitted to New Zealand hospitals with a heart attack each year.
The new $150,000 research project was partly inspired by an Australian study involving several hundred patients that compared the amounts of oxygen given to patients and suggested that smaller volumes should be administered.
"This study suggested that, actually, it's possible it could be doing harm - and that's meant people have been more conservative about giving oxygen - but we really don't know, and the only real way of sorting it out is to do a systematic comparison."
His team will carry out a randomised trial that will focus on patients who present with heart attacks.
They will assess two different common strategies for giving oxygen - one to all heart attack patients and the other only if blood oxygen is reduced.
The researchers will then look at whether the number of people who die within 30 days of treatment differs between the two strategies.
The study would have no effect on what therapies are given, he said.
Even if a change in oxygen therapy did have an impact in the outcome of a patient's case, it would still be small compared with the factors like speeding up the time between heart attack and treatment, or other treatments proven to be highly beneficial, he said.
"But even a small impact is a small impact on a lot of people - and we would like to know."
The new study, announced by the Heart Foundation today, shares in $1.7 million in new funding for research and cardiology training.
The foundation's medical director, Dr Gerry Devlin, said heart disease was still the number one killer in New Zealand.
Focus turns to Pasifika
Why are Maori and Pacific Island people more likely to die from heart attacks? In a new study, Auckland University's Dr Corina Grey will get to grips with this question that has long troubled health researchers in New Zealand.
Recent research led by Dr Grey revealed how Maori and Pacific people admitted to hospital after suffering major heart events were 1.5 times more likely than Europeans to die within 28 days, and twice more likely within a year. Further, this was irrespective of the patients' age, sex or socio-economic status, she said.
In a new $90,000 project, Dr Grey will investigate what causes these differences, which were also seen in patients who lived in areas of high deprivation.
"Knowledge of where inequalities occur will then enable us to develop targeted strategies and interventions to improve care for all New Zealanders."
Dr Grey will look for answers using the Anzacs-QI research programme, which gives detailed information about all patients admitted to hospitals with a heart attack or unstable angina.
Today marks World Heart Day. To find out more, visit worldheartday.org or heartfoundation.org.nz.
Read more science stories by Jamie Morton here.
