Candela Diaz-Canestro1, Thomas Haider2, Carsten Lundby3, David Montero1. 1. Libin Cardiovascular Institute of Alberta, University of Calgary, Canada. 2. University Heart Center, University Hospital Zurich, Switzerland. 3. Inland Norway University of Applied Sciences, Lillehammer, Norway.
Abstract
INTRODUCTION: Notwithstanding recent progress on molecular mechanisms underlying heart failure with preserved ejection fraction (HFpEF), multiple pathophysiological aspects of this condition including the basis of anemia and other hematological disorders remain unresolved. In this study, we sought to determine the relationship of plasma volume (PV), a plausible confounding factor for the concentration of solutes in blood, with key haematological markers in HFpEF patients. METHODS: Total circulating PV was determined with high-precision, automated carbon-monoxide rebreathing in 24 stable HFpEF patients (70 ± 8 yr, left ventricular ejection fraction = 55±5 %) and 18 healthy age- and sex-matched control (HC) individuals. Linear regression analyses were performed to determine the association of PV with a comprehensive set of hematological variables. RESULTS: Hematocrit (40·1 ± 4·9 vs. 43·6 ± 2·7 %, P = 0·004) and hemoglobin concentration (131 ± 16 vs. 142 ± 7 g·l-1 , P = 0·003) were reduced in HFpEF patients compared with HC individuals. In regression analyses, PV was negatively associated with hematocrit (r=-0·45, P = 0·029) and hemoglobin concentration (r=-0·44, P = 0·030) in HFpEF patients, whereas these variables were not associated with PV in HC individuals (P ≥ 0·198). Regarding blood electrolytes, PV was negatively associated with K+ (r=-0·43, P = 0·036) and Ca2+ (r=-0·44, P = 0·032) in HFpEF patients but not in HC individuals (P ≥ 0·734). None of the above associations were detected in HFpEF patients when using ideal instead of measured PV. CONCLUSION: The blood concentration of routine markers of anemia and electrolyte balance are specifically and linearly associated with PV in HFpEF patients. Excess or deficit of circulating PV may confound clinical diagnosis in this population.
INTRODUCTION: Notwithstanding recent progress on molecular mechanisms underlying heart failure with preserved ejection fraction (HFpEF), multiple pathophysiological aspects of this condition including the basis of anemia and other hematological disorders remain unresolved. In this study, we sought to determine the relationship of plasma volume (PV), a plausible confounding factor for the concentration of solutes in blood, with key haematological markers in HFpEFpatients. METHODS: Total circulating PV was determined with high-precision, automated carbon-monoxide rebreathing in 24 stable HFpEFpatients (70 ± 8 yr, left ventricular ejection fraction = 55±5 %) and 18 healthy age- and sex-matched control (HC) individuals. Linear regression analyses were performed to determine the association of PV with a comprehensive set of hematological variables. RESULTS: Hematocrit (40·1 ± 4·9 vs. 43·6 ± 2·7 %, P = 0·004) and hemoglobin concentration (131 ± 16 vs. 142 ± 7 g·l-1 , P = 0·003) were reduced in HFpEFpatients compared with HC individuals. In regression analyses, PV was negatively associated with hematocrit (r=-0·45, P = 0·029) and hemoglobin concentration (r=-0·44, P = 0·030) in HFpEFpatients, whereas these variables were not associated with PV in HC individuals (P ≥ 0·198). Regarding blood electrolytes, PV was negatively associated with K+ (r=-0·43, P = 0·036) and Ca2+ (r=-0·44, P = 0·032) in HFpEFpatients but not in HC individuals (P ≥ 0·734). None of the above associations were detected in HFpEFpatients when using ideal instead of measured PV. CONCLUSION: The blood concentration of routine markers of anemia and electrolyte balance are specifically and linearly associated with PV in HFpEFpatients. Excess or deficit of circulating PV may confound clinical diagnosis in this population.
Authors: James O M Plumb; James M Otto; Shriya B Kumar; Mark Wright; Walter Schmidt; Michael P W Grocott; Hugh E Montgomery Journal: Physiol Rep Date: 2020-03