Abstract 12282: Obesity Paradox in Patients with Ischemic Heart Disease - A Virtual Histology Intravascular Ultrasound Study

Abstract

Background: The higher body mass index (BMI) has been reported to associate with favorable prognosis in patients with congestive heart failure. Recently, in vivo assessment of coronary plaque composition has become available using virtual-histology IVUS (VH-IVUS). However, the relation between coronary plaque composition and BMI is unclear in patients with ischemic heart disease (IHD).

Objectives: The purpose of this study was to clarify the difference in coronary plaque composition according to BMI.

Methods: Culprit and non-culprit coronary artery lesions from 195 (ACS75.9%) patients who underwent percutaneous coronary interventions were imaged by IVUS. Patients were divided into 3 groups according to BMI values (L-group: BMI<20 (n=20), M-group: 20<BMI<25 (n=105), H-group: 25<BMI (n=70)). Plaque composition was classified into four categories by VH-IVUS software: green (Fibrous); yellow-green (Fibro-Fatty); white (Dense Calcium); red (Necrotic Core).

Results: There were no significant differences in gender, LDL-C, HDL-C, and HbA1c among 3 groups. However, age, the frequency of ACS, Dense calcium (DC) and Necrotic core (NC) were significantly lower in H-group than in M and L-group (62.5±10.4 vs 67.1±10.5 vs 67.5±9.5, p=0.01; 65.2% vs 74.1% vs 95.2%, p=0.02; 7.8±6.2% vs 12.7±8.6% vs 13.4±6.0%, p=0.0002; 17.0±9.1% vs 21.8±10.2% vs 23.9±7.1%, p=0.002) in non-culprit lesions, as well as in culprit lesions, in which DC was significantly lower in H-group than in M and L-group (9.0±6.3 vs 12.7±10.7 vs 15.4±9.2, p=0.02). Multivariate regression analysis revealed that BMI (p=0.017) was an independent determinant factor of fibrous tissue rate. Similarly, age was an independent determinant factor of fibro-fatty tissue rate (p=0.001), and DC (p=0.009), ACE-I/ARB (p=0.010) usage was an independent determinant factor of fibro-fatty tissue rate (p=0.00003) and necrotic core (p=0.010).

Conclusions: High BMI was associated with lower amount of DC, NC, and lower incidence of ACS in patients with ischemic heart disease. BMI, age and ACE-I/ARB usage were also independent determinant factors of coronary plaque composition.