SAGE-Hindawi Access to Research International Journal of Nephrology Volume 2011, Article ID 198045, 9 pages doi:10.4061/2011/198045 Review Article Vascular and Valvular Calciﬁcation in Chronic Peritoneal Dialysis Patients Angela Yee-Moon Wang University Department of Medicine, Queen Mary Hospital, University of Hong Kong, 102 Pok Fu Lam Road, Hong Kong Correspondence should be addressed to Angela Yee-Moon Wang, aymwang@hku.hk Received 24 May 2011; Accepted 8 June 2011 Academic Editor: Domenico Russo Copyright © 2011 Angela Yee-Moon Wang. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Cardiovascular disease accounts over half of the total mortality in peritoneal dialysis (PD) patients. In addition, there is an increasing recognition of a high prevalence of vascular and valvular calciﬁcation that may contribute to the increased all-cause and cardiovascular mortality in the PD patients. Disturbed mineral metabolism in association with chronic kidney disease has been suggested as one of the major contributing factors to the increased vascular/valvular calciﬁcation in this population. In this paper, we provide an overview of the prevalence and importance of this complication in the PD patients. In addition, we review the contributing factors and some emerging mechanisms for this complication. Furthermore, we discuss some therapeutic strategies that may be useful in limiting the progression of vascular/valvular calciﬁcation in the PD population. 1. Introduction Cardiovascular disease is the leading cause of death in end-stage renal disease (ESRD) patients receiving long-term peritoneal dialysis (PD) therapy. Data from the Canada and United States (CANUSA) Peritoneal Dialysis Study showed that nearly half of the mortality in PD patients was due to cardiovascular disease [1]. According to data from the United State Renal Data System (USRDS), this trend has remained more or less the same in the recent years [2]. Vascular/valvular calciﬁcations are important and highly prevalent complications in ESRD patients including those receiving PD therapy and very much contributed to the exceedingly high cardiovascular mortality in this population. Numerous observational cohort studies demonstrated the prognostic importance of vascular/valvular calciﬁcation in ESRD patients. Using plain radiographs to estimate number of arterial sites with calciﬁcation including carotid artery, abdominal aorta, and iliofemoral axis, both the presence and extent of vascular calciﬁcations are strong predictors of cardiovascular and all-cause mortality in the ESRD patients [3]. Abdominal aortic calciﬁcation detected nonquantita- tively using plain lateral abdominal radiographs has also been shown to be an independent predictor of all-cause mortality and cardiovascular death in hemodialysis patients [4]. Using multislice computed tomography (MSCT) that enables quantiﬁcation of calciﬁcation, Block et al. demonstrated a signiﬁcant mortality eﬀect of the severity of coronary artery calcium score in incident hemodialysis patients [5]. Cardiac valvular calciﬁcation, detected using echocardiography, also predicts all-cause mortality and cardiovascular death in chronic PD patients. Notably, patients with both aortic and mitral valvular calciﬁcation showed the highest risk of mortality and cardiovascular death compared to those with either heart valve calciﬁcation or no valve calciﬁcation [6]. These data suggest that the presence of vascular or valvular calciﬁcation, irrespective of the sites involved, is indicative of a poor prognosis in the dialysis population including patients on PD. In this paper, we reviewed the prevalence, signiﬁcance, contributing factors, and emerging mechanisms for this important complication in the PD population. Furthermore, we discussed therapeutic strategies that may be useful in retarding calciﬁcation burden in the PD patients. 2. Prevalence of Vascular and Valvular Calciﬁcation in PD Patients The reported prevalence of coronary artery calciﬁcation in the ESRD patients ranged from 40% to nearly 100% [7–14]. So far, a majority of the studies were done in hemodialysis