and nanoparticle transport in blood. It could also be used as a diagnostic tool in

cancer and pathogen detection.

Its analytical (Bai et al. 2018) usage lies in biopharmaceutical production where

one can monitor and optimize protein drug production as well as in the analysis

related to human cells. Microfluidic devices could also be employed in assessing

diffusion coefficient, visibility, pH, and chemical binding coefficients.

Nanofluidics has the potential to integrate into microfluidic systems resulting in

structures which are broadly called as lab-on-a-chip. One such example could be

when NCAMs are integrated with the microfluidic devices and hence could be used

as a digital switch which can easily transfer fluid from one microfluidic channel to

another. In the process, it could selectively isolate and transfer analytes proficiently

on the basis of size and mass mix reactants. It can also help separate fluids with

disparate characteristics. One can draw a natural correlation between the capabilities

of nanofluidic structures in handling fluids and thus controlling the flow of electrons

and holes by electronic components. Such an analogy has been fruitfully used to

understand active electronic functions which could be rectification and field effect

and bipolar transistor action. In addition, nanofluidics find applications in nano-

optics wherein microlens array could be produced which are tunable. With the

advent of lab-on-a-chip devices, nanofluidics find effective role not only in medicine

and biotechnology but also in clinical diagnostics for PCR and related techniques.

16.4

Quantification of PET Myocardial Blood Flow

For patients with alleged coronary artery disease (CAD), it becomes imperative to

manage and diagnose them by noninvasive method along with their risk assessment.

To get an estimate of myocardial ischemia and the involved risk, a quantitate

assessment of myocardial perfusion is carried out with the help of numerous

techniques (Waller et al. 2014; Nesterov et al. 2016) such as positron emission

tomography (PET), cardiac magnetic resonance (CMR), single-photon emission

computed tomography (SPECT), and cardiac computed tomography perfusion

(CTP). Such techniques prove to be very helpful in assessing the extent of CAD,

especially in patients with multivessel diseases by measuring myocardial blood flow

and coronary flow reserve. In addition, these imaging techniques have proficiency to

demarcate the level and severity of diffuse atherosclerosis and microvascular dys-

function. This also eliminates any biasing of intermediate observer.

In a healthy coronary vessel, any change in the myocardial oxygen triggers a local

endothelial facilitated release of nitric oxide and subsequent arteriolar dilation along

with reduced resistance in the microvasculature and thus ensuing increased

myocardial perfusion. However, in case of patients with atherosclerosis, microvas-

cular dysfunction results in a restricted coronary vasodilator response to an increased

demand of oxygen resulting in myocardial ischemia. Clinically, help is taken either

through exercise or pharmacological vasodilators to achieve the coronary

hyperemia.

16

Role of Microfluidics and Nanofluidics in Managing CAD

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