TCT: CABG gains on PCI for cost benefits in high-risk patients
SAN FRANCISCO—The 23rd annual Transcatheter Cardiovascular Therapeutics conference was in full swing on Nov. 9, but David J. Cohen, MD, already had his eyes on the 2012 event. In a presentation on the cost-effectiveness of PCI compared with CABG, he said that results favored bypass surgery, especially when looking at high-risk patients with multivessel acute coronary syndromes (ACS). He proposed that five-year results from the SYNTAX trial, due in 2012, will show an even stronger advantage for CABG.

“In the high-risk SYNTAX group, bypass surgery already is an attractive strategy, and I predict that at this meeting next year when we have this data, we will see that bypass surgery is not only attractive but also cost-saving and lifesaving,” said Cohen, director of cardiovascular research at Saint Luke’s Mid-America Heart Institute in Kansas City.

One-year results from the SYNTAX trial showed the rates of major adverse cardiac or cerebrovascular events were 17.8 percent in the PCI group compared with 12.4 percent in the CABG group. The two procedures had similar rates of death and MI at 12 months but the rate of stroke was higher in the CABG arm. (N Engl J Med 2009;360:961-972).

Procedure costs for PCI were higher than for CABG but PCI had initial hospital costs of almost $5,700 less, Cohen said. Total one-year costs were nearly $3,600 lower for PCI, but follow-up costs were almost $2,300 higher in the PCI group. CABG showed better angina relief and quality of life over the three-year follow-up, and PCI’s cost advantage diminished after three years.

“Initially, bypass surgery is substantially more costly but over time, particularly within the first two to three years, there is a lot of catch up,” Cohen said. “If you wait long enough for the mortality benefits for bypass surgery, you will see attractive results.”

CABG’s gains over PCI came through substantially lower costs for rehospitalizations and medications, Cohen noted, which for PCI patients in the SYNTAX trial included dual antiplatelet therapy for a year after the procedure.

“But that’s the story for the average SYNTAX patient,” Cohen said. “What happens when we look at the subgroups? If we segregate patients by the same tertiles of SYNTAX score that we use to predict prognosis, then we can see that they strongly predict cost savings.”

In a subgroup analysis, the total one-year cost for PCI in the low-risk group was $6,154 less than for CABG, with net costs for PCI 20 percent lower; in the middle-risk group, $3,889 less for PCI, with net costs 8 percent lower; and in the high-risk group, only $467 less for PCI, with net costs neutral. “In the middle strategy, we are moving toward equanimity,” he said. “But there still are cost savings with PCI.”

A cost-effectiveness analysis of CABG versus PCI by SYNTAX score tertile found an incremental cost effectiveness ratio (ICER) of $43,000 per quality of life year in the high-risk group but no similar benefit in the other tertiles. “As we get into the high SYNTAX score tertile, we see that the situation has shifted," Cohen said. “Bypass surgery is equal in cost to PCI over a year follow-up, the quality of life year expectancy is favoring bypass surgery and the cost-effectiveness ratio is already favorable.

“What we know now after four years of follow-up is the survival advantage is strong in this group,” he concluded. “I predict that next year when we complete the five-year cost-effectiveness analysis from the SYNTAX score, you are going to see a very favorable cost for bypass surgery, especially in this high-risk group.”