title: Hereditary spherocytosis and elliptocytosis associated with prosthetic heart valve replacement: rheological study of erythrocyte modifications.
abstract: The implantation of a prosthetic heart valve (HVP) in patients with hereditary spherocytosis (HS) and hereditary elliptocytosis (HE) is rare, and the changes in the structure and deformability of erythrocytes that follow implantation in these patients have been poorly described. In the present study, the erythrocytes in HS and HE patients with mechanical HVP were compared to the erythrocytes in patients with only congenital membrane defects, in terms of biochemical modifications and rheological behaviour. Integral and cytoskeletal erythrocyte membrane proteins were studied, and blood viscosity (shear rate/shear stress ratio), aggregation ratio [eta(1 s(-1))/eta(200 s(-1))], and red cell visco-elasticity were determined. Valve replacement with a mechanical prosthesis worsened anaemia and resulted in a change in haemolysis, from sub-clinical to evident. The rheological investigation of erythrocytes from HS patients confirmed the characteristic increased viscosity and aggregation ratio and the decreased deformability. The rheological behaviour of erythrocytes from patients with HVP showed a decrease in viscosity and an increase in elastic modulus. In these patients, the prosthesis seems to have induced traumatic damage to the erythrocyte membrane, leading to fragmentation and lysis, which in turn modified rheological parameters. The biochemical and rheological investigation allowed us to understand the clinical and haematological pictures of the patients and to describe the role played by different factors in haemolytic anaemia.
authors.affiliation: Department of Haematology, Oncology and Molecular Medicine, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161, Rome, Italy. patrizia.caprari@iss.it.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Caprari
authors.affiliation: Department of Haematology, Oncology and Molecular Medicine, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161, Rome, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Tarzia
authors.affiliation: Miane, Treviso, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Mojoli
authors.affiliation: Day Hospital Talassemici, S. Eugenio Hospital, Rome, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Cianciulli
authors.affiliation: Centro Aziendale Produzione Emocomponenti Azienda Ospedaliera S.Camillo, Forlanini, Rome, Italy.
authors.forename: Emilio
authors.initials: E
authors.lastname: Mannella
authors.affiliation: Centro Aziendale Produzione Emocomponenti Azienda Ospedaliera S.Camillo, Forlanini, Rome, Italy.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Martorana
mesh_terms: D000328:Adult; D004548:Elasticity; D004612:Elliptocytosis, Hereditary / Q000150:complications*; D004912:Erythrocytes; D005260:Female; D006331:Heart Diseases / Q000150:complications* / Q000601:surgery*; D006350:Heart Valve Prosthesis; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D008875:Middle Aged; D012212:Rheology; D013103:Spherocytosis, Hereditary / Q000150:complications*
chemical_list: D008565:Membrane Proteins