Debut of DES Failed to Alter Survival Benefit of CABG vs PCI in Multivessel Disease
|Researchers led by Mark A. Hlatky, MD, of the Stanford University School of Medicine (Stanford, CA), looked at 38,277 Medicare patients with multivessel disease who were revascularized in the BMS era (January 1999-April 2003) and 43,645 patients treated in the DES era (May 2003-December 2006).|
|Each PCI patient was propensity-score matched with a CABG patient from the same era. Patients were also matched by the year of index procedure, diabetes status, and age within 1 year. While baseline characteristics of patients in the BMS era were generally different from those of patients in the DES era, most differences were considered small.|
Comparable 5-Year Survival
Five-year survival improved from the BMS era to the DES era at similar rates for both PCI (+1.2%) and CABG (+1.1%), although the incidence of MACE (death, MI, and repeat revascularization) declined more with PCI (-5.7%) than with surgery (-0.9%). There was no interaction between the time period of treatment and the effect of CABG vs PCI for death or death/MI, but for MACE, the comparative effectiveness of CABG was greater in the BMS era than in the DES era (table 1).
Further adjustment for diabetes, heart failure, peripheral vascular disease, and tobacco use did not affect the results.
Dr. Hlatky and colleagues say the study “suggests that the introduction of drug-eluting stents was not associated with a material change in the comparative effectiveness of multivessel CABG vs multivessel PCI for the hard outcomes of death or MI. Overall, multivessel CABG remained associated with lower hazards of death and MI over 5 years of follow-up in the DES era.”
Superiority of DES Over BMS Not at Issue
Comparing PCI with contemporary CABG, the study authors say, “provides indirect evidence about the effect of DES on hard outcomes of multivessel PCI.” They note that evaluation of this effect has been difficult due to the “rapid and virtually complete adoption of DES soon after [their] introduction.”
“While the question of whether hard clinical outcomes were reduced by DES compared with BMS is of interest, the well-established effect of DES in reducing repeat coronary revascularization procedures has made this an academic question, since DES [have] almost completely replaced BMS in contemporary PCI,” Dr. Hlatky and colleagues say.
They note some limitations of the study, including the nonrandom selection of patients for receipt of CABG or PCI and the use of Medicare claims, which do not include data on several clinical variables that affect outcomes, such as the number of diseased vessels and patient frailty.
Hlatky MA, Boothroyd DB, Baker LC, Go AS. Impact of drug-eluting stents on the comparative effectiveness of coronary artery bypass surgery and percutaneous coronary intervention. Am Heart J. 2014;Epub ahead of print.
- Dr. Hlatky reports no relevant conflicts of interest.