A new US study confirms earlier findings that patients receiving delayed treatment for heart attack do just as well and have similar long term quality of life with drugs alone as with drugs plus a stent to prop open a blocked artery; the new study also shows that non-invasive drug options are cheaper.
The study was the work of lead author Dr Daniel Mark, a member of the Outcomes Research Group at the Duke Clinical Research Institute in Durham, North Carolina, and colleagues, and was published on 19 February in the New England Journal of Medicine, NEJM.
Mark said in a press statement that the finding was:
“Just one more reason to question the use of routine stenting in late-treatment patients when cheaper, less invasive options are just as effective.”
About 1 million Americans have heart attacks every year in the US and studies show that the sooner patients are treated the better, ideally within the first two hours of an attack.
However for about a third of heart attack patients the reality is they don’t get treatment until more than 12 hours after their symptoms appear. Many of these are found to have a completely blocked artery and many doctors are of the view that this should be treated by putting in a stent to prop it open, since it is too late for clot busting drugs.
The Occluded Artery Trial (OAT) was set up to compare treatment with drugs alone versus drugs plus stenting among patients who did not receive treatment for their heart attack until days and even weeks after onset of symptoms.
Dr Judith Hochman from New York University and Mark and colleagues presented the initial results of the trial in an earlier paper where in a group of 2,166 patients, drugs only therapy was just as effective as drugs plus PCI (percutaneous coronary intervention where balloons and stents are used to unblocked clogged arteries) in treating stable heart attack patients whose treatment was delayed.
In this latest study, Mark, Hochman and colleagues enrolled 951 patients from the same OAT trial and compared the quality of life issues between those treated with drugs alone and those treated with drugs plus PCI.
The patients in the new study had suffered a heart attack between 3 to 28 days before enrollment and had a completely blocked artery and although classed as high risk they were clinically stable and did not have chest pains. All had received the optimal drug therapy, but half of them had been randomly assigned to receive PCI as well.
Quality of life measures were taken at month 4, month 12 and month 24 when the participants filled in questionnaires comprising a number of recognized scales. These included: the DASI, the Duke Activity Status Index to assess cardiac function; a 36-item short form version of the Medical Outcomes Study scale to assess things like pain, physical limitations, vitality and social function; and the Mental Health Inventory, which assesses psychological wellbeing.
The researchers also compared costs of treatment for 458 of 469 patients who were treated in the US.
The results showed that:
- At month 4, the patients who had drugs and PCI reported less chest pain and had a higher DASI score than the ones in the drugs only group.
- However, those differences gradually disappeared over the period of the study.
- By the end of the study, the patients in the drugs only group appeared to be doing just as well as those who had drugs and PCI.
- During the first month of treatment, the drugs plus PCI group stayed in the hospital 1.2 days longer compared to the drugs only group, mostly because of longer stays in intensive care.
- The average medical cost for the first 30 days following treatment was 22,859 dollars for the drugs and PCI group, and only 12,683 dollars for the drugs only group.
- The overall cumulative 2-year costs were about 7,000 dollars higher for the drugs plus PCI group.
The researchers concluded that:
“PCI was associated with a marginal advantage in cardiac physical function at 4 months but not thereafter. At 2 years, medical therapy remained significantly less expensive than routine PCI and was associated with marginally longer quality-adjusted survival. “
Mark said that:
“What we have here is one of those cases where less is more.”
“While it may seem that going an extra step in opening up clogged arteries even days after a heart attack, we know that clinically, it doesn’t seem to offer the advantages we expected. Coupling that with the higher cost, we now know that adding PCI to standard medical care in opening blocked arteries more than a day after a heart attack is not good value,” he added.
He said this study showed how it was possible to offer high quality of care at less cost.
The National Heart, Lung, and Blood Institute supported the study. Their director, Dr Elizabeth G Nabel said:
“All heart attack patients should seek treatment right away to limit damage to the heart muscle.”
“For the one-third of patients who do not receive immediate care – but who are otherwise stable – we have greater evidence of how treatments really affect them,” she added, emphasizing that:
“Medical care is not just about immediate results and survival, but it is also about providing good quality of life and minimizing medical costs.”
“Quality of Life after Late Invasive Therapy for Occluded Arteries.”
Mark, Daniel B., Pan, Wenqin, Clapp-Channing, Nancy E., Anstrom, Kevin J., Ross, John R., Fox, Rebecca S., Devlin, Gerard P., Martin, C. Edwin, Adlbrecht, Christopher, Cowper, Patricia A., Ray, Linda Davidson, Cohen, Eric A., Lamas, Gervasio A., Hochman, Judith S., the Occluded Artery Trial Investigators.
N Engl J Med Volume 360, Number 8, pp 774-783, February 19, 2009.
Sources: Journal abstract, DukeHealth.org.
Written by: Catharine Paddock, PhD