ORLANDO, FL— Cutting the use of drug-eluting stents (DES) in half in low-risk patients undergoing percutaneous coronary intervention (PCI) could save roughly $205 million a year without significantly increasing the risk of target vessel revascularization (TVR), according to study results presented November 16, 2011, at the American Heart Association Scientific Sessions.

Amit P. Amin, MD, and colleagues at Saint Luke’s Mid America Heart Institute (Kansas City, MO), calculated the risk of TVR after PCI for patients in the National Cardiovascular Data Registry (NCDR) for catheterization and PCI (CathPCI). The investigators used the MassDAC TVR risk model, which identifies the patients who would most benefit from PCI based on a prior coronary intervention, the need for salvage or an emergency intervention, the presence of peripheral vascular disease or diabetes, and angiographic characteristics.

TVR risk was stratified according to the likelihood of restenosis in the following year:

• Low risk: equal to or less than 10%
• Moderate risk: 10% to less than 20%
• High risk: 20% or greater

DES Use Common Even in Low-Risk Patients

In the CathPCI registry, physician variation in DES use ranged from 2% to 100% with a median rate ratio of 1.8. This implies that, after adjusting for patient factors related to DES use, a median 80% variation in DES use can be attributed to physician preference, Dr. Amin said.

Analysis of CathPCI patients revealed that 43.0% were at low risk for restenosis, 43.6% were at moderate risk, and 13.2% were at high risk.

Yet DES were used in similar proportions of patients regardless of TVR risk. DES were implanted in 73.9% of patients at low risk, 78% at moderate risk, and 83.2% at high risk.

The cost-effectiveness of DES was compared for the existing pattern of use in CathPCI patients against a model of “judicious use.” The latter was defined as a reduction in DES use from present level of 73.9% to 36.8% in low-risk patients.

Importantly, Dr. Amin said, this change in the pattern of stent choice would have a negligible effect on the restenosis rate, increasing it from 8.36% to 8.38%.

From a cost standpoint, Dr. Amin estimated that a shift to more judicious use of DES would save about $205 million per year. This includes a savings of $171 million from eliminating DES for the low-risk patient group and an additional $95 million from eliminating the need for long-term clopidogrel therapy for these patients. Some of this, however, would be offset by an increase of $65 million in costs associated with the small increase in TVR under the judicious model.

“Reducing DES in low-risk patients would produce large potential cost savings and would be offset by a trivial increase in TVR. Even modest changes in DES use could result in substantial savings to patients and payers alike,” Dr. Amin concluded.

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