Impact of visit-to-visit variability in blood pressure on coronary plaque as assessed by integrated backscatter intravascular ultrasound.

INTRODUCTION: Visit-to-visit variability (VVV) in blood pressure (BP) has been reported to be a strong predictor of cardiovascular disease. However, the association between VVV in BP and coronary plaque composition has not been fully elucidated. METHODS: One hundred-two consecutive patients with coronary artery disease (CAD) who underwent percutaneous coronary intervention (PCI) using integrated backscatter (IB) intravascular ultrasound (IVUS), and who had at least six clinic visits a year before PCI were included. We measured systolic and diastolic BP (SBP and DBP) at each visit and determined VVV in BP expressed as the standard deviation of the average BP. Grayscale and IB IVUS examinations were performed for the culprit lesion of a coronary artery just before PCI. RESULTS: There were no significant associations between the average SBP or DBP and various IVUS parameters. However, VVV in SBP was positively correlated with both the percentage (%) of atheroma volume (ß = 0.23, p = .02) and % lipid volume (ß = 0.53, p < .0001). VVV in DBP was positively correlated with % lipid volume (ß = 0.24, p = .01), while there was no significant correlation between VVV in DBP and % atheroma volume. A  multivariable linear regression analysis showed that VVV in SBP was independently associated with % atheroma volume (p = .04) and % lipid volume (p < .001). CONCLUSIONS: Larger VVV in SBP was significantly associated with an increased plaque burden and lipid composition at the culprit lesion of a coronary artery in CAD patients. The improvement of VVV in SBP may contribute to the regression and stabilization of coronary plaques.

Influence of chronic kidney disease on coronary plaque components in coronary artery disease patients with both diabetes mellitus and hypertension.

Chronic kidney disease (CKD) is well known to be associated with an increased incidence of coronary artery disease (CAD). Diabetes mellitus (DM) and hypertension (HTN), both of which are traditional risk factors for CAD, are the two most common causes of CKD. However, the influence of CKD on coronary atherosclerosis in CAD patients who have both DM and HTN remains uncertain. In these patients, we examined the relationship between CKD and coronary plaque using integrated backscatter intravascular ultrasound (IB IVUS). Two hundred two CAD patients with both DM and HTN who underwent percutaneous coronary intervention using IB IVUS were included. The patients were divided into two groups: CKD group (n = 106) and non-CKD group (n = 96). Gray-scale and IB IVUS examinations were conducted for the non-culprit segment of a coronary artery. As a result, although there was no significant difference in the percentage of plaque volume, the percentage of lipid volume was significantly higher in the CKD group than in the non-CKD group [median (IQR): 56.7% (45.4-67.0%) vs. 52.0% (38.3-60.2%), p = 0.03]. In all of the patients, estimated glomerular filtration rate levels were negatively correlated with the percentage of lipid volume (r = - 0.15, p = 0.03) and positively correlated with the percentage of fibrosis volume (r = 0.15, p = 0.04). A multivariate regression analysis showed that CKD was an independent predictor associated with the increased lipid volume (ß = 0.15, p = 0.047) and decreased fibrosis volume (ß = - 0.16, p = 0.03) in coronary plaques. In conclusion, among CAD patients who had both DM and HTN, CKD was associated with lipid-rich coronary plaques. CKD may contribute to the vulnerability of coronary plaque in these very high-risk patients.