Mathematical Study of the Perturbation of Magnetic Fields Caused by Erythrocytes.

The purpose of this chapter is the mathematical study of the perturbation of a homogeneous static magnetic field caused by the embedding of a red blood cell. Analytical expressions for the magnetic potential and the magnetic strength vector are derived. From the obtained results, it emerges that the magnetic field inside the red blood cell is not uniform and the magnitude depends on the orientation of the erythrocyte.

Qualitative Differences Between the Semi-separable and the "Almansi-Type" Stokes Stream Function Expansions in the Study of Biological Fluids.

The creeping motion of a Newtonian fluid around particles simulating the relative motion of biological fluids such as blood plasma flow past red blood cells can be modeled through Stokes equations in spheroidal coordinates. By employing a stream function ψ, the irrotational and the rotational Stokes flow are described through a second- and a fourth-order elliptic-type partial differential equations: Eψ = 0 and Eψ = 0, respectively. Firstly, the complete set of the solution expansion has been obtained, in terms of particular combinations of Gegenbauer functions, in separable and semiseparable forms.

Early Impact of the COVID-19 Pandemic on Congenital Heart Surgery Programs Across the World: Assessment by a Global Multi-Societal Consortium.

The coronavirus disease 2019 (COVID-19) pandemic currently gripping the globe is impacting the entire health care system with rapidly escalating morbidities and mortality. Although the infectious risk to the pediatric population appears low, the effects on children with congenital heart disease (CHD) remain poorly understood. The closure of congenital heart surgery programs worldwide to address the growing number of infected individuals could have an unintended impact on future health for COVID-19-negative patients with CHD.

A Microscale Mathematical Blood Flow Model for Understanding Cardiovascular Diseases.

The blood plasma flow through a swarm of red blood cells in capillaries is modeled as an axisymmetric Stokes flow within inverted prolate spheroidal solid-fluid unitary cells. The solid internal spheroid represents a particle of the swarm, while the external spheroid surrounds the spheroidal particle and contains the analogous amount of fluid that corresponds to the fluid volume fraction of the swarm. Analytical expansions for the components of the flow velocity are obtained by introducing a stream function ψ which satisfies the fourth-order partial differential equation Eψ = 0.

Surgical Management of Aorto-Ventricular Tunnel. A Multicenter Study.

Aorto-ventricular tunnel (AoVT), a rare congenital anomaly, is a channel originating in the ascending aorta just above the sinotubular junction and leading to the cavity of the left ventricle (AoLVT), or, rarely, the right (AoRVT). This study reviews our collective 30-year experience with the surgical treatment of AoVT. Data were submitted by 15 participating centers on 42 patients who underwent correction of AoVT between 1987 and 2018.

Late management of the aortic root after repair of tetralogy of Fallot: A European multicentre study.

Objectives: We sought to determine the indications, type, and outcomes of reoperations on the aortic root after repair of tetralogy of Fallot (TOF).

Methods: Eleven centers belonging to the European Congenital Heart Surgeons Association contributed to the data collection process. We included 36 patients who underwent surgical procedures on the aortic root, including surgery on the aortic valve and ascending aorta, between January 1975 and December 2017.

Remarkably Still Repairable Large Aortopulmonary Window in an Adult Patient.

Aortopulmonary window (APW) is an abnormal congenital connection between the main pulmonary artery (MPA) and the ascending aorta, with intact aortic and pulmonary valves, leading to heart failure or, if not repaired early, to pulmonary vascular obstructive disease. We report the rare case of an asymptomatic adult with an unrestrictive APW, whose pulmonary arterial hypertension was remarkably still reversible, permitting successful repair.

Anomalous aortic origin of coronary arteries: Early results on clinical management from an international multicenter study.

Background: Anomalous aortic origin of coronary arteries (AAOCA) is a rare abnormality, whose optimal management is still undefined. We describe early outcomes in patients treated with different management strategies.

Methods: This is a retrospective clinical multicenter study including patients with AAOCA, undergoing or not surgical treatment.

Left-Sided Reoperations After Arterial Switch Operation: A European Multicenter Study.

Background: We sought to report the frequency, types, and outcomes of left-sided reoperations (LSRs) after an arterial switch operation (ASO) for patients with D-transposition of the great arteries (D-TGA) and double-outlet right ventricle (DORV) TGA-type.

Methods: Seventeen centers belonging to the European Congenital Heart Surgeons Association (ECHSA) contributed to data collection. We included 111 patients who underwent LSRs after 7,951 ASOs (1.

Translation of two aggregated low-density lipoproteins within blood plasma: a mathematical model.

Arteriosclerosis is a disease in which the artery walls get thicker and harder. Atherosclerosis is a specific form of arteriosclerosis which allows less blood to travel through the artery and increases blood pressure. Low-density lipoproteins (LDLs) and their ability to aggregate are important in atherosclerosis.