Cardiovascular diseases represent the leading cause of death worldwide, with the World Health Organization reporting that 17.9 million people died due to this presentation in 2019, accounting for 32% of all global deaths.1 Cardiovascular disease encompasses several individual conditions that impact the patient's heart and blood vessels, posing a significant challenge for healthcare providers. Atherosclerosis occurs due to hyperlipidemia and lipid oxidation and is defined as the most prevalent cause of cardiovascular diseases.2 Intimal plaques of the vascular system characterize an atherosclerotic presentation from the aorta to the coronary arteries.3

The current diagnostic criteria for atherosclerosis rely primarily on imaging techniques, including an angiogram. However, current diagnostic procedures fail to provide insights into the plaque burden and composition4; hence, utilizing nanotechnology could prove beneficial in resolving these limitations. Moreover, available treatment is solely preventative instead of curative. The current literature highlights that the high cost of novel compounds and the lack of substantial evidence in large randomized controlled trials limit the use of more beneficial therapies in clinical practice.5 To that respect, researchers have utilized their resources to investigate the application of nanotechnology to enhance current clinical paradigms for the diagnosis and subsequent management of cardiovascular diseases.6

Nanotechnology is defined by Saini et al.7 as "the science and engineering involved in the design, synthesis, characterization, and application of materials and devices whose smallest functional organization, in at least one dimension, is on the nanometer scale or one billionth of a meter." Therefore, employing nanotechnology for diagnosis and drug delivery is expected to alter the pharmaceutical and biotechnology industries' foundations. This novel technology has applications in cancer diagnosis and therapy8 antibody-based therapies,9 and the diagnosis and drug delivery in cardiovascular diseases,10 in addition to a host of other healthcare sectors. The primary objectives of nanotechnology in a clinical setting are to enhance the delivery of poorly water-soluble drugs, target the delivery of drugs in a specific manner, whether that be cell- or tissue-specific, enable transcytosis of drugs across both the epithelial and endothelial barriers, facilitate the delivery of 2 or more drugs to enable combination therapy, and finally, to enhance the delivery of prominent macromolecule drugs to the intracellular sites of action.11

This review aims to discuss the different approaches in which nanotechnology can be applied in the diagnosis and drug delivery of cardiovascular diseases. Moreover, the potential therapeutic impact of nanoparticle technology will also be reviewed in detail. The review question was constructed following the review's aims, allowing relevant MeSH terms to be identified for use in the search strategy. A thorough literature search was conducted using several citation databases, with any articles reaped being screened for relevance against the inclusion and exclusion criteria. Data extraction and analysis of the differing nanotechnology and its employment for the diagnosis and drug delivery in atherosclerosis are compared and contrasted with the current literature. Finally, any similarities and differences between nanotechnology designs and applications are analyzed to identify the optimal patient tool.