Role of coronary physiology in the contemporary management of coronary artery disease

Abstract

Coronary artery disease (CAD) remains the leading cause of death worldwide with approximately 1 in 30 patients with stable CAD experiencing death or acute myocardial infarction each year. The presence and extent of resultant myocardial ischaemia has been shown to confer an increased risk of adverse outcomes. Whilst, optimal medical therapy (OMT) forms the cornerstone of the management of patients with stable CAD, a significant number of patients present with ischaemia refractory to OMT. Historically coronary angiography alone has been used to determine coronary lesion severity in both stable and acute settings. It is increasingly clear that this approach fails to accurately identify the haemodynamic significance of lesions; especially those that are visually “intermediate” in severity. Revascularisation based upon angiographic appearances alone may not reduce coronary events above OMT. Technological advances have enabled the measurement of physiological indices including the fractional flow reserve, the index of microcirculatory resistance and the coronary flow reserve. The integration of these parameters into the routine management of patients presenting to the cardiac catheterization laboratory with CAD represents a critical adjunctive tool in the optimal management of these patients by identifying patients that would most benefit from revascularisation and importantly also highlighting patients that would not gain benefit and therefore reducing the likelihood of adverse outcomes associated with coronary revascularisation. Furthermore, these techniques are applicable to a broad range of patients including those with left main stem disease, proximal coronary disease, diabetes mellitus, previous percutaneous coronary intervention and with previous coronary artery bypass grafting. This review will discuss current concepts relevant to coronary physiology assessment, its role in the management of both stable and acute patients and future applications.

Keywords: Ischaemia, Coronary physiology, Coronary flow reserve, Fractional flow reserve, Coronary artery disease

Core tip: Coronary artery disease remains the leading cause of death worldwide. There is increasing evidence to suggest that the use of invasive coronary angiography alone may not reliably identify all lesions associated with haemodynamic compromise. Technological advances have enabled the measurement of a number of coronary physiological indices which when incorporated into routine practice are associated with improved outcomes, reduced risks and greater economy. This review will discuss current concepts relevant to coronary physiology assessment, its role in the management of both stable and acute patients and future applications.