FREEDOM Sets Us Free—for the Sickest Diabetics

 
 
 
 - Diabetes
 

In November 2009, Cardiovascular Business asked if the much-anticipated FREEDOM trial would “set us free” by better informing decisions to treat high-risk diabetics with multivessel disease using either PCI or CABG. The findings demonstrated resounding support for surgery, but some physician experts are concerned that the decisions may overlook the patient’s perspective on risks, such as stroke, and that these results may get translated to lower-risk diabetics.

'Practice-changing trial'

 
  Source: Elizabeth A. Magnuson, PhD

In real-life clinical practice, one-third of the patients who undergo cardiac catheterization and PCI have diabetes with multivessel disease—similar to the FREEDOM population, according to senior author Valentin Fuster, MD, PhD, director of Mount Sinai Heart in New York City and past-president of the American Heart Association.

In the trial, Fuster et al enrolled 1,900 patients (mean age, 63.1 years, 29 percent women and 83 percent had three-vessel disease) at 140 international centers from 2005 through 2010 (N Engl J Med 2012;367:2375-2384). After five years, the CABG group had a lower combined rate of strokes, MIs and deaths (18.7 percent) than the PCI group (26.6 percent).

“FREEDOM, a well-conducted, practice-changing trial, demonstrated that CABG is the preferred strategy for most diabetics with multivessel disease, particularly if there aren’t simple, straightforward lesions, and a mammary artery can be used to bypass the left anterior descending (LAD) coronary artery,” says interventional cardiologist Peter B. Berger, MD, chairman of cardiology at Geisinger Health System and co-director of the Geisinger Heart & Vascular Institute in Danville, Pa.

“Until this study, there were no clear guidelines to direct physicians for these patients, and it was left to a case-by-case basis,” says Fuster. “Any diabetic patient with significant coronary disease who is scheduled for a cardiac catheterization should be informed about the results favoring CABG, if this is what is found at the time of catheterization.” In the evolving drug-eluting stent (DES) era, the difference between adverse events for CABG vs. DES will not be a greater than 8 percent, he adds.

Stroke, a well-known risk of bypass surgery, occurred more often in the CABG group (5.2 percent) than in the PCI group (2.4 percent). However, more people died from any cause in the PCI group (16.3 percent) than in the CABG group (10.9 percent). The survival advantage of CABG over PCI was consistent regardless of race, gender, number of blocked vessels or disease severity, according to the study authors.

“If you were to look solely at death and MI, CABG is clearly superior in this trial,” says Ajay J. Kirtane, MD, chief academic officer and director of the interventional cardiology fellowship program at NewYork-Presbyterian Hospital and Columbia University Medical Center in New York City. “But the two procedures are clearly different from a patient perspective, particularly with regards to the invasive nature of the two procedures and the increased stroke risk, especially within 30 days.”

Conversely, Fuster calls the risk of stroke “relative,” if a physician considers the number of events with heart attack and mortality that are avoided. “The risk of stroke is minimal, compared with what you gain. Regardless, all the risks and benefits of both procedures need to be addressed with the patient.”

To better assess these risks, this “study reaffirms the heart team strategy,” Kirtane adds. “For the past five years in our practice, if we are presented with a diabetic patient with multivessel disease, interventionalists take the patient off the cath lab table to consult with a surgeon.”

While repeat revascularization drove many of the outcomes, particularly the economic outcomes, of FREEDOM, Berger says “death and stroke are much more important to physicians and patients.” Kirtane adds that the risk of stroke may be even more compelling to some patients than mortality.

Mark A. Hlatky, MD, of Stanford University School of Medicine in Stanford, Calif., wrote in the accompanying editorial that mortality has been consistently reduced by CABG compared with PCI, in more than 4,000 patients with diabetes who have been evaluated in 13 clinical trials (N Engl J Med 2012;367:2437-2438). “The controversy should finally be settled,” he wrote.

However, Hlatky concurred with Kirtane that informed decision-making is necessary for patients and specialists. He wrote there