麻豆传媒

Percutaneous coronary intervention (PCI) is used for only a fraction of patients with unprotected left main coronary artery stenosis, according to results of a large registry study.

Of 131,044 patients with stenosis of at least 50% of the left main coronary artery, just 4.3% underwent PCI over a five-year period, and the rest were referred for surgery or medical management, according to J. Matthew Brennan, MD, MPH, of Duke University Medical Center in Durham, N.C., and colleagues.

Stenting was generally used for patients who were at high surgical risk, the researchers reported in the February 14 issue of the Journal of the American College of Cardiology.

Medicare patients who underwent PCI had a high risk of dying within 30 months (42.7%) and of having a major adverse event (57.9%). That risk was lower among those who received drug-eluting stents instead of bare metal stents (inverse probability weighted HR 0.84, 95% CI 0.73 to 0.96).

"These results emphasize the need for a well-powered randomized clinical trial examining the safety and effectiveness of percutaneous revascularization in patients with unprotected left main coronary artery disease," the researchers wrote.

Use of PCI for unprotected left main stenosis, which has typically been treated with surgery, is controversial, they said.

The American College of Cardiology and American Heart Association previously recommended that PCI not be performed in these patients but, in 2007, the groups updated the recommendation to indicate that PCI may be considered.

Brennan and colleagues set out to evaluate national trends in the use of PCI in this patient population using information from the National Cardiovascular Data Registry's CathPCI registry for 2004 to 2008.

During that time, the percentage of patients with unprotected left main stenosis who received PCI was low but increased from 3.8% in 2004 to 4.9% in 2008 (P<0.0001).

On average, the patients who underwent PCI were older (mean age 72 versus 68.5), had a heavier burden of chronic comorbidities, and were more likely to have a high EuroSCORE (13.4% versus 3.8%) compared with the patients who did not receive PCI.

The stented patients also were more likely to present with ST-segment elevation MI (13.4% versus 9.4%) and non-STEMI (24.8% versus 18.7%).

In-hospital mortality rates ranged from 2.9% for elective PCI to 45.1% for emergent or salvage cases.

To evaluate the outlook for patients who receive PCI, the researchers tracked 30-month mortality and a composite of major adverse events (death, myocardial infarction, and revascularization) in a subgroup of 2,765 patients 65 and older who could be linked to Medicare inpatient claims files.

By 30 months, 42.7% died, 8.2% had an MI, and 17.5% underwent repeat revascularization.

The patients at highest risk for one of those outcomes were those with high EuroSCORE values (76.6% versus 53.9%), high clinical urgency (74.2% versus 52.8%), and bifurcation lesions (64.8% versus 54.7%).

Receiving a drug-eluting stent was associated with a lower mortality rate, but not a lower rate of the composite of death, MI, or repeat revascularization.

"The mechanism by which stent type affects the risk of death in this population remains unclear," the authors noted.

They acknowledged some limitations of the study, including the uncertain reliability of the reporting of diagnostic-only procedures, the inability to perform a direct comparison of outcomes from PCI, surgery, and medical management, and the possible influence of reporting errors and detection biases for outcomes drawn from inpatient claims data.

From the American Heart Association:

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