Background: The purpose of the present study was to use virtual histology-intravascular ultrasound (VH-IVUS) to evaluate the relationship between microalbuminuria and plaque components in 920 patients.
Methods and results: Patients with albumin levels <30mg/g creatinine were defined as having normoalbuminuria (n=824), and those with albumin levels 30-300mg/g as having microalbuminuria (n=96). The microalbuminuria group contained more patients with acute coronary syndrome (ACS; 72% vs. 61%, P=0.018) and more patients with diabetes (53% vs. 26%, P<0.001). In ACS patients, %necrotic core (NC) volume was significantly greater in the microalbuminuria group compared with the normoalbuminuria group (19±10% vs. 15±9%, P=0.019), but not in patients with stable angina. In ACS patients, thin-cap fibroatheroma (TCFA) was observed more frequently in the microalbuminuria group (36% vs. 18%, P=0.008), and microalbuminuria was the independent predictor of TCFA (odds ratio [OR], 1.106; 95% confidence interval [CI]: 1.025-1.144, P=0.018). In diabetic patients, %NC volume was significantly greater in the microalbuminuria group compared with the normoalbuminuria group (20±9% vs. 16±10%, P=0.017), but not in non-diabetic patients. In diabetic patients, TCFA was observed more frequently in the microalbuminuria group (38% vs. 17%, P=0.002) and microalbuminuria was the independent predictor of TCFA (OR, 1.120; 95%CI: 1.038-1.204, P=0.012).
Conclusions: Microalbuminuria was associated with a higher number of vulnerable plaque components in ACS and diabetic patients. More intensive medical therapy is needed to stabilize the vulnerable plaque if microalbuminuria is observed in diabetic ACS patients.