Background: Recent studies have demonstrated that patients with chronic kidney disease are at high risk of atherosclerosis. Recently it has been found that coronary plaque components can be evaluated by integrated backscatter intravascular ultrasound (IB-IVUS), and lipid-rich plaque is associated with vulnerable plaque. The aim of the study was to investigate the relationship between renal function and tissue characterization of coronary plaque composition at the target stenotic site for percutaneous coronary intervention (PCI).
Methods: We prospectively performed IB-IVUS before elective PCI in 89 consecutive patients with stable angina. According to estimated glomerular filtration rate (eGFR), they were divided into two groups (eGFR <60 ml/min/ 1.73 m(2) or eGFR > or =60 ml/min/1.73 m(2)). The tissue characteristics of the coronary plaque at each target stenotic site were evaluated by three-dimensional (3D) IB-IVUS just before PCI procedure.
Results: The patients with eGFR <60 ml/min/1.73 m(2) had higher percentage of lipid volume and lower percentage of fibrous volume compared to the patients with eGFR > or = 60 ml/min/1.73 m(2) on the 3D IB-IVUS images (36.7 +/- 10.6% versus 28.7 +/- 9.3%, P < 0.001 and 59.1 +/- 8.7% versus 66.3 +/- 8.3%, P < 0.001, respectively). eGFR showed a significant negative correlation with lipid volume and had a significant positive correlation with fibrous volume in coronary plaques (r = -0.44, P < 0.0001, and r = 0.46, P < 0.0001, respectively).
Conclusions: Impaired renal function was related to higher percentage of lipid volume and lower percentage of fibrous volume in coronary plaque. Our findings may explain the increasing risk of cardiovascular events in patients with renal dysfunction.