Lessons from CARDia for Patients with Diabetes and Complex Disease 
    
Key Points:

Revascularization continues to evolve for this challenging patient subgroup.

By TCT Daily Staff

The results of the CARDia trial have added to the growing understanding of the challenges of revascularization in patients with diabetes and multivessel disease, said Kevin J. Beatt, PhD, MBBS, of Mayday University Hospital, London.

CARDia was initially presented at the European Society of Cardiology Congress 2008. Beatt, a primary investigator of the study, discussed the impact of it at a session on Tuesday.

Noninferiority not shown in CARDia

CARDia compared PCI and CABG in diabetic patients (n=510) with either multivessel or complex single-vessel disease who were eligible for either treatment. PCI was conducted with both sirolimus-eluting stents (71%) and bare-metal stents (29%). As previously reported at the ESC Congress 2008, noninferiority criteria were not met for the primary endpoint, a composite of death, nonfatal MI, and nonfatal stroke at one year (10.2% for CABG vs. 11.6% for PCI; P=.63). However, with the addition of repeat revascularizations, the difference in the composite endpoint at one year significantly favored CABG over PCI (11.0% vs. 17.3%; P=.04).

BARI: Inspiration for CARDia

According to Beatt, the CARDia trial "represents the past and present work in 20 years of investigation for diabetics." The issue of revascularization in this patient subset, he noted, "goes back to the BARI trial, where the problems of diabetics were first highlighted."

BARI found no significant difference in seven-year survival for patients without diabetes who were treated with either CABG or PTCA (86.4% vs. 86.8%, respectively). However, in the diabetic subgroup, CABG resulted in significantly higher seven-year survival compared with angioplasty (76.4% vs. 55.7%, respectively; P=.0011).

"There were two important lessons [from BARI]. The first is that diabetics were an important subgroup in terms of revascularization, and [the second is] that there was a need for long-term follow-up to properly determine the value of these two treatment strategies," Beatt said.

"In 2001, when [CARDia] was conceived, the conventional wisdom was that diabetic patients with complex disease or even single LAD disease should undergo bypass surgery for revascularization. This was a strongly held [idea] in many quarters that made it difficult to undertake angioplasty in these patients," he continued, noting that this situation was what inspired the CARDia investigators to initiate a trial hypothesizing that optimal PCI was noninferior to CABG for this subgroup.

Today’s patients more complex

Beatt pointed out that, based on data from the ARTS I trial, outcomes for patients with diabetes have improved significantly over the years. "Whatever the results were previously, at the turn of the century, they are much better now," he said.

In addition, trials are enrolling patients who require increasingly longer stents, indicating that investigators are willing to recruit ever more complex patients.

"In summary," Beatt concluded, "complex diabetic patients remain the most challenging group for revascularization, both for surgeons and interventional cardiologists."

Disclosures:

Dr. Beatt reports no relevant conflicts of interest.

（source：www.tctmd.com）