Coronary Microvascular Dysfunction and the Role of Noninvasive Cardiovascular Imaging

Abstract

Patients with coronary microvascular dysfunction (CMD) have significantly higher rates of cardiovascular events, including hospitalization for heart failure, sudden cardiac death, and myocardial infarction (MI). In CMD, several pathophysiological changes lead to functional and structural abnormalities in the coronary microvasculature, which disrupt the ability of the vessels to vasodilate and augment myocardial blood flow in response to increased myocardial oxygen demand, causing ischemia and angina. With the advent of more advanced non-invasive cardiac imaging techniques, the coronary microvasculature has been subjected to more intense study in the past two decades—this has led to further insights into the diagnosis, pathophysiology, treatment, prognosis and follow-up of CMD. This review will highlight and compare the salient features of the currently available non-invasive imaging modalities used in these patients, and discuss the clinical utility of these techniques in the workup and management of these patients.

SPECT myocardial perfusion imaging identifies myocardial ischemia in patients with a history of COVID-19 without coronary artery disease

“…In the heart, one of the organs connected to microvascular circulation, hemodynamics and metabolic homeostasis are regulated by the coronary microvasculature [ 8 , 24 ]. In primary CMD without obstructive coronary artery disease, functional and structural abnormalities in the coronary microvasculature impair the vessels’ ability to increase myocardial blood flow and vasodilation function, leading to ischemia and angina if myocardial oxygen demand is increased [ 25 ]. SARS-Cov-2 causes the down-regulation of ACE-2, which is involved in the inactivation of angiotensin II; in addition, the hyperactivation of angiotensin II causes vasoconstriction, hypertrophy, fibrosis, and the release of reactive oxygen species [ 26 ].…”

Research Progress of Imaging Methods for Detection of Microvascular Angina Pectoris in Diabetic Patients

“…This achieves good results in preventing diabetic cardiomyopathy. The limitation of MCE in evaluating coronary microvascular function is that its accuracy is interfered with by many factors, such as the technical level of operators and patient's situation ( 79 ). In a word, MCE is a potential technology with advantages of low cost, simple operation, and no ionizing radiation, these makes it play a unique role in the preliminary screening of coronary microvascular angina pectoris.…”

MINOCA: One Size Fits All? Probably Not—A Review of Etiology, Investigation, and Treatment

“…This potential is the so-called flow reserve. In ischemic territories, endogenous mechanisms will lead to a basally more dilated coronary bed, and therefore with less flow reserve [ 83 ]. Measuring CFR attempts to evaluate the potential to increase blood flow in response to specific stimuli.…”