FREEDOM Lends Strong Support To CABG For Diabetics With Multivessel Disease

Editor’s note: The embargo on FREEDOM was lifted early after a press release was published by mistake.)

Diabetics with multivessel disease do better with CABG than PCI, according to FREEDOM (Future Revascularization Evaluation in Patients with Diabetes Mellitus: Optimal Management of Multivessel Disease), a large NIH-sponsored study presented at the American Heart Assocation in Los Angeles and published simultaneously in the New England Journal of Medicine.

The study was designed to evaluate the  relative worth of the two revascularization procedures in diabetics with multivessel disease. Although many studies, including BARI, ARTS, CARDia, and SYNTAX, suggested that CABG was more effective than PCI in this population, PCI has remained a popular procedure in this group. Now, many experts agreed here in Los Angeles, FREEDOM may well dampen enthusiasm for PCI in this group.

In the trial, 1900 patients were randomized to either PCI with a drug-eluting stent or CABG. After followup for at least two years the primary outcome– the composite of death, nonfatal MI, or nonfatal stroke– occurred more often in the PCI group. There were more deaths and MIs in the PCI group but more strokes in the CABG group:

Here are the 5-year event rates:

Composite endpoint: 26.6% in the PCI group versus 18.7% in the CABG group (p=0.005)

• Deaths: (16.3% versus 10.9%, p=0.049) but more strokes in the CABG group
• MI: 13.9% versus 6%, p<0.001)
• Stroke: 2.4% versus 5.2%, (p=0.03)

The results in favor of CABG were consistent across all the prespecified subgroups, including severity of disease as assessed by the SYNTAX score.

In an accompanying editorial, Mark Hltaky discussed the resistance of many cardiologists to accepting that CABG is superior to PCI in this patient population. Previous studies were dismissed because they were outdated, an argument that Hlatky labels “a catch-22, since long-term studies are needed to compare hard outcomes, but evidence from long-term studies may be ignored if therapies are evolving.” In particular, PCI advocates  have proposed that the use of drug-eluting stents would close the gap between PCI and CABG.

Now, he writes, 17 years after the NHLBI issued a clinical alert based on the results of the BARI trial, FREEDOM “provides compelling evidence of the comparative effectivesness of CABG versus PCI.”

He concludes:

“The results of the FREEDOM trial suggest that patients with diabetes ought to be informed about the potential survival benefit from CABG for the treatment of multivessel disease. These discussions should begin before coronary angiography in order to provide enough time for the patient to digest the information, discuss it with family members and members of the heart team, and come to an informed decision.”

At an AHA press conference, David O. Williams said that FREEDOM “provides meaningful information to help” cardiologists choose the best therapy for their patients and that it will cause “a definite change in practice.”

At the same press conference, Alice Jacobs said that FREEDOM might result in CABG receiving a class 1 recommendation in the guidelines. Now, she said, “one would think long and hard” about offering PCI to diabetics with multivessel disease.

Mandatory YouTube Link for this trial:

Here is the AHA press release:

Bypass surgery significantly better than stents for treating multiple blockages in diabetics

American Heart Association Late-Breaking Clinical Trial Report – Embargoed until 4:58 p.m. PT/ 7:58 p.m. ET

November 04, 2012

Study Highlights:

• Patients with diabetes who have multiple clogged heart arteries fared significantly better when treated with bypass surgery than drug-covered stents.
• These patients were less likely to die or have a heart attack within five years if they underwent bypass surgery compared to treatment with drug-coated stents.

LOS ANGELES, Nov. 4, 2012 — Patients with diabetes  who have multiple heart blockages fare significantly better if they undergo bypass surgery  instead of being treated with drug-covered stents , according to late-breaking trial results presented at the American Heart Association’s Scientific Sessions 2012.

The full manuscript for the the Future REvascularization Evaluation in patients with Diabetes mellitus: Optimal management of Multivessel disease (FREEDOM) Trial is published in the New England Journal of Medicine.

Researchers studied1,900 patients with diabetes, about 19 percent of those who underwentbypass surgery  suffered a heart attack  or stroke  or died within five years, as compared to almost 27 percent of those who received a drug-covered stent .

“These results were very striking,” said Valentin Fuster, M.D., the study’s lead researcher and director of Mount Sinai Heart at the Mount Sinai Medical Center in New York. “In a majority of places in the world, these patients were receiving stents. This is going to change practice.”

The type of patients in the study — those with diabetes and heart disease that affected more than one coronary artery — represents about a quarter of the patients seen in catheterization labs for heart procedures.

In the study, researchers randomly assigned patients at 140 centers globally to receive either bypass surgery or drug-eluting stents, which are tiny, medicine-coated mesh tubes that prop open clogged arteries. All study patients were prescribed medications to control their blood pressure, cholesterol and blood sugar based on current treatment guidelines.

Researchers followed patients’ progress from 2005- 2010. Those undergoing bypass surgery had fewer deaths and heart attacks. However, they had more strokes — 5.2 percent versus 2.4 percent — not enough to negate the net significant benefits of fewer deaths and heart attacks, Fuster said.

Earlier studies in this group of patients showed that bypass was favorable compared to angioplasty. However, many of those studies did not use stents that were covered in medicine that helps prevent the risk of new blockages within the stents themselves.

“But the cardiology community didn’t know if that held true when compared exclusively to newer, drug-covered stents,” said Fuster. “So we are so excited to find the answer.”

In the trial, 29 percent of the patients were female, the average age was about 63 years and the average time since receiving the diagnosis of diabetes was about 10 years. The majority, 83 percent, had coronary disease in three arteries.

“We always want to know how long the effects last.” Fuster said. “The gap could begin to close or the results could get better and better. So, longer follow-up is critical.”

His team is seeking additional funding to continue follow-up of these patients.

Co-author is Michael E. Farkouh, M.D.

The National Institutes of Health funded the study.

Disclosures are here http://newsroom.heart.org/pr/aha/document/DISCLOSURES.pdf 

Follow news from the American Heart Association’s Scientific Sessions 2012 via Twitter:@HeartNews .  

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