Clinical Significance of On-Treatment Triglyceride Level in Patients Treated by Percutaneous Coronary Intervention for Non-ST-Segment Elevation Acute Coronary Syndrome

BACKGROUND/AIMS: The use of statins in patients with acute coronary syndrome (ACS) has increased, and reduced levels of low-density lipoprotein cholesterol (LDL-C) lead to lower coronary event rates. We studied the effect of lipid levels during statin treatment on prognosis in patients with ACS and percutaneous coronary intervention (PCI). METHODS: Between January 2005 and May 2007, 325 ACS patients who underwent PCI and received statins were evaluated. We measured serum lipid levels at baseline and 4 weeks. The relationships between on-treatment levels of triglyceride (TG) and LDL-C and one-year major adverse cardiac events (MACE) were assessed. RESULTS: At 4 weeks, the mean LDL-C level was 72.5±23.8 mg/dL and the mean TG was 123.2±62.8 mg/dL. MACE occurred in 41 cases (12.6%). Baseline serum lipid levels were similar between the patients with and those without MACE. However, the patients with MACE showed significantly higher TG level at 4 weeks (149.6±81.4 vs. 119.3±58.9 mg/dL, p=0.026) than those without. High on-treatment TG level (≥150 mg/dL) were associated with increased adverse events compared to lower TG level in a univariate analysis (hazard ratio [HR], 3.3; p<0.001). In a multivariate analysis, high 4-week TG level after statin treatment was an independent predictor for MACE (HR, 4.01; 95% confidence interval, 1.85 to 9.06; p=0.001), however, baseline TG and LDL-C levels were not. CONCLUSIONS: High on-treatment TG level (≥150 mg/dL) was associated with a higher risk of MACE. This finding supports the concept that achieving low TG levels may be an important therapeutic parameter in statin-treated patients following ACS and PCI.