January 30th, 2012
Very Large Observational Study Finds Significant Mortality Advantage for CABG Over PCI in High-Risk Patients
Larry Husten, PHD
Although PCI has a small, early mortality benefit compared to CABG in high-risk patients, after the first year a striking survival advantage for CABG develops, according to results of the ASCERT study, presented on Monday at the annual meeting of the Society of Thoracic Surgeons (STS).
Fred Edwards presented the high-risk subset of ASCERT (ACCF-STS Database Collaboration on the Comparative Effectiveness of Revascularization Strategies), an NHLBI-funded study based on linked data from the STS, the ACC, and CMS. (The full results of ASCERT will be presented in March at the ACC scientific sessions.) The study population included patients 65 or older with 2- or 3-vessel disease who underwent CABG or PCI from 2004 through 2007. Some 189,793 patients were followed in the study; 103,549 underwent PCI and 86,244 underwent CABG.
At 4 years, there was a 22% risk reduction in adjusted mortality in the CABG group compared to the PCI group (RR, 0.78; CI, 0.74-0.82). A similar pattern was observed in patients regardless of age, sex, diabetes status, and ejection fraction.
“Previous observational studies have shown a long-term survival advantage for CABG over PCI. These partial ASCERT results confirm that in important high-risk clinical subsets the CABG survival advantage can also be seen in a large nationwide population,” said Edwards in an STS press release.
President of the Society for Cardiovascular Angiography and Interventions (SCAI), Dr Christopher White (Ochsner Medical Center, New Orleans, LA), told heartwire that although SCAI supports ASCERT, the study should not be interpreted as a direct comparison between the two therapies.
“This is not a comparison. This was never comparison of patients. This is a description in a database of what happens when patients are treated one way or another,” he said. “What this report really says is that we are really good at picking out which patients do better with surgery and which patients do better with stenting. They are not the same patients getting those treatments. So it’s crazy for someone to say that surgery is better than stenting. That’s not what this is about. When see a patient in my clinic and I think they have problems that warrant surgery, I refer them there and they get surgery, but when I see someone who needs stenting, I do that,” he said.
“There’s a whole number of patients who are too ill and too high risk to get surgery, so those patients are offered [PCI] and often the reasons for not doing surgery is that the patients have comorbidities . . . which also kill them,” he said. “There’s no way to risk-adjust that kind of information because the outcomes are too divergent.
“If you really want to know whether surgery is better than stenting, you have to do the randomized trial, and those are out there. That’s what SYNTAX is, [for example],” he said.