The Impact of Postoperative Discontinuation or Continuation of Chronic Statin Therapy on Cardiac Outcome After Major Vascular Surgery

Abstract

BACKGROUND: Statins reduce cardiac morbidity in nonsurgical populations, and may benefit surgical patients. We sought to examine cardiac outcome in patients who continued, compared with those who discontinued, statin therapy after major vascular surgery. METHODS: Prospectively collected data were examined for an association between statin therapy and perioperative cardiac morbidity in patients undergoing infrarenal aortic surgery. Between January 2001 and December 2003, there were no guidelines for perioperative continuation of statins (discontinuation group, n = 491). From January 2004, guidelines were instituted whereby statin therapy was continued starting as soon as possible after surgery (continuation group, n = 178). The occurrence of cardiac myonecrosis (defined as an increase of cardiac troponin I more than the 99th percentile or 0.2 ng/mL) was analyzed. Intra-cohort (propensity score) and extra-cohort (Lee score) adjustments of the risk were performed. RESULTS: The median delay between surgery and resumption of statin therapy was 4 days and 1 day in the discontinuation and continuation groups (P < 0.001), respectively. Using propensity score matching for likelihood of preoperative treatment, the odds ratio associated with chronic statin treatment to predict myonecrosis for patients with versus without early postoperative statin resumption (continuation versus discontinuation groups) was 0.38 and 2.1 (relative risk reduction of 5.4; 95% confidence interval: 1.2-25.3, P < 0.001), respectively. The odds ratio after adjustment for the Lee score was 0.38 in the continuation group and 2.1 in the discontinuation group (relative reduction of 5.5; 95% confidence interval: 1.2-26.0, P < 0.001). Postoperative statin withdrawal (>4 days) was an independent predictor of postoperative myonecrosis (OR 2.9, 95% confidence interval 1.6-5.5). CONCLUSIONS: Discontinuation of statin therapy after major vascular surgery is associated with an increased postoperative cardiac risk, suggesting that statin therapy should be resumed early after major vascular surgery.