title: Factors associated with subendocardial ischemia risk in patients on hemodialysis.
abstract: Bone metabolism disorder (BMD) and vascular dysfunction contribute to excess cardiovascular mortality observed in hemodialysis patients. Vascular dysfunction, a new marker of atherosclerosis, can play a role in this risk. Even though associated with higher mortality in the general population, such vascular evaluation in patients on hemodialysis has not been extensively studied.
  
  
  
  In this cross-sectional study, hemodialysis patients were submitted to flow-mediated dilation, subendocardial viability ratio (SEVR) and ejection duration index assessment, in order to estimate the impact of BMD markers on vascular dysfunction.
  
  
  
  A matched cohort of patients with (n = 16) and without (n = 11) severe secondary hyperparathyroidism (SHPT) was studied. Additionally, time spent under severe SHPT was also evaluated. Patients with severe SHPT had lower SEVR and higher ejection duration index, indicating higher cardiovascular risk. Lower SEVR was also associated to diastolic blood pressure (r = 0.435, p = 0.049), serum 25-Vitamin-D levels (r = 0.479, p = 0.028) and to more time spent under severe secondary hyperparathyroidism (SHPT), defined as time from PTH > 500pg/ml until parathyroidectomy surgery or end of the study (r = -0.642, p = 0.027). In stepwise multiple regression analysis between SEVR and independent variables, lower SEVR was independently associated to lower serum 25-Vitamin-D levels (p = 0.005), female sex (p = 0.012) and more time spent under severe SHPT (p = 0.001) in a model adjusted for age, serum cholesterol, and blood pressure (adjusted r² = 0.545, p = 0.001).
  
  
  
  Subendocardial perfusion was lower in patients with BMD, reflecting higher cardiovascular risk in this population. Whether early parathyroidectomy in the course of kidney disease could modify such results still deserves further investigation.
authors.affiliation: Hospital das Clínicas - Universidade de São Paulo.
authors.forename: Bruno Caldin da
authors.initials: BC
authors.lastname: Silva
authors.affiliation: Hospital das Clínicas - Universidade de São Paulo.
authors.forename: Adriano
authors.initials: A
authors.lastname: Sanjuan
authors.affiliation: Instituto do Coração - Universidade de São Paulo.
authors.forename: Valéria
authors.initials: V
authors.lastname: Costa-Hong
authors.affiliation: Hospital das Clínicas - Universidade de São Paulo.
authors.forename: Luciene Dos
authors.initials: LD
authors.lastname: Reis
authors.affiliation: Hospital das Clínicas - Universidade de São Paulo.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Graciolli
authors.affiliation: Hospital das Clínicas - Universidade de São Paulo.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Consolim-Colombo
authors.affiliation: Instituto do Coração - Universidade de São Paulo.
authors.forename: Luiz Aparecido
authors.initials: LA
authors.lastname: Bortolotto
authors.affiliation: Hospital das Clínicas - Universidade de São Paulo.
authors.forename: Rosa Maria Affonso
authors.initials: RM
authors.lastname: Moyses
authors.affiliation: Hospital das Clínicas - Universidade de São Paulo.
authors.forename: Rosilene Motta
authors.initials: RM
authors.lastname: Elias
mesh_terms: D001851:Bone Diseases, Metabolic / Q000209:etiology; D003430:Cross-Sectional Studies; D004699:Endocardium; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications / Q000628:therapy; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000453:epidemiology* / Q000209:etiology; D006435:Renal Dialysis; D012307:Risk Factors