Stress testing and non-invasive coronary angiography in patients with suspected coronary artery disease: time for a new paradigm

Diagnosis and management of coronary artery disease represents major challenges to our health care system, affecting millions of patients each year. Until recently, the diagnosis of coronary artery disease was possible only through cardiac catheterization and invasive coronary angiography. To avoid the risks of an invasive procedure, stress testing is often employed for an initial assessment of patients with suspected coronary artery disease, serving as a gatekeeper for cardiac catheterization. With the emergence of non-invasive coronary angiography, the question arises if such a strategy is still sensible, particularly, in view of only a modest agreement between stress testing results and the presence of coronary artery disease established by cardiac catheterization. Much data in support of the diagnostic accuracy and prognostic value of non-invasive coronary angiography by computed tomography have emerged within the last few years. These data challenge the role of stress testing as the initial imaging modality in patients with suspected coronary artery disease. This article reviews the clinical utility, limitations, as well as the hazards of stress testing compared with non-invasive coronary artery imaging by computed tomography. Finally, the implications of this review are discussed in relation to clinical practice

Static and Dynamic Solid-Water Interfaces: charge regulation, diffusio-osmosis and heterogeneous electrokinetics

The results presented in this thesis consists of three parts, each with a different view of a solid-water interface. In the first part we consider the case where both the interface and the fluid are static, and investigate the interface between muscovite mica and water for varying salt species and concentration. By combining two experimental techniques, we obtain detailed information of both the number and location of the adsorbed ions, and we construct a model of the interface consistent with all data. In the second part we consider again a static interface but with a dynamic fluid, where water flows from one reservoir to another through a microscopic channel. We construct a theoretical model to predict the transport of water, charge and salt through a channel from one reservoir to the other as a function of the reservoir and channel properties, specifically in the context of reverse electrodialysis, where an electric current is generated by mixing salt and fresh water. We furthermore investigate the transport properties of an array of microscopic channels, i.e. a membrane. We elaborate why the current generated by a membrane is very different from a single channel. In the last part we investigate a system with both a dynamic interface and fluid, as experiments have shown that ions adsorbed in the interface are laterally mobile and are chemically exchanged with the fluid. We show how and why this can significantly alter the transport properties of these microscopic channels

Static and Dynamic Solid-Water Interfaces: charge regulation, diffusio-osmosis and heterogeneous electrokinetics

The results presented in this thesis consists of three parts, each with a different view of a solid-water interface. In the first part we consider the case where both the interface and the fluid are static, and investigate the interface between muscovite mica and water for varying salt species and concentration. By combining two experimental techniques, we obtain detailed information of both the number and location of the adsorbed ions, and we construct a model of the interface consistent with all data. In the second part we consider again a static interface but with a dynamic fluid, where water flows from one reservoir to another through a microscopic channel. We construct a theoretical model to predict the transport of water, charge and salt through a channel from one reservoir to the other as a function of the reservoir and channel properties, specifically in the context of reverse electrodialysis, where an electric current is generated by mixing salt and fresh water. We furthermore investigate the transport properties of an array of microscopic channels, i.e. a membrane. We elaborate why the current generated by a membrane is very different from a single channel. In the last part we investigate a system with both a dynamic interface and fluid, as experiments have shown that ions adsorbed in the interface are laterally mobile and are chemically exchanged with the fluid. We show how and why this can significantly alter the transport properties of these microscopic channels