Coronary artery bypass graft surgery in acute coronary syndrome: incidence, cost impact, and acute clopidogrel interruption.

BACKGROUND

Guidelines stipulate that clopidogrel should be interrupted ≥ 5 days prior to elective coronary artery bypass graft (CABG) surgery to reduce the risk of bleeding unless the need for revascularization and/or the net benefit of the clopidogrel outweighs the potential risks of bleeding. This study describes real-world patterns of acute clopidogrel use, CABG surgery, and inpatient costs among patients with acute coronary syndrome (ACS).

METHODS

The study used the MarketScan® Commercial, Medicare Supplemental, and Hospital Drug databases, comprising health care data for > 63 million individuals in the United States. Acute coronary syndrome episodes, defined as hospitalizations for ACS (primary International Classification of Diseases, Ninth Revision, Clinical Modification codes 410.xx, 411.1x) occurring between January 1, 2005 and June 30, 2009, were identified from patients aged ≥ 18 years. Outcomes included cost of and length of stay (LOS) for ACS episodes and, among patients experiencing ACS episodes treated with acute clopidogrel administration followed by CABG surgery, the duration of clopidogrel interruption prior to CABG surgery. Analyses were descriptive.

RESULTS

A total of 160 168 ACS episodes were identified, and the mean patient age was 63.5 years. Coronary artery bypass graft surgery episodes comprised 9.3% (14 896 of 160 168) of all ACS episodes. The mean LOS was 9.8 (standard deviation [SD], 6.8) days per CABG surgery episode, and mean inpatient costs were $71 140 (SD, $68 012) per CABG surgery episode. Among patients experiencing ACS episodes with inpatient drug data and to whom acute clopidogrel was administered followed by CABG surgery (n = 8101), the mean duration of clopidogrel interruption was 3.3 (SD, 2.6) days, and the majority (62.1%) of these patients underwent surgery within 1 to 3 days after their last acute clopidogrel dose. The mean incremental increase in inpatient costs associated with 1 extra LOS day was $1991.

CONCLUSION

Coronary artery bypass graft surgery is used relatively infrequently among patients who experience ACS episodes. When CABG surgery is performed in a real-world setting, the majority or procedures are performed < 5 days after the last acute clopidogrel dose. However, among patients for whom urgent CABG surgery is not indicated, withholding CABG surgery to allow for clopidogrel interruption may only minimally affect inpatient costs and must be considered in the broader context of patient management.