Non-invasive imaging techniques to assess myocardial perfusion.

Coronary artery disease affecting myocardial perfusion continues to be the leading cause of cardiovascular morbidity and mortality worldwide. While invasive evaluation based on coronary angiography and flow measurements still is considered the reference technique for assessing myocardial perfusion, technological evolutions in noninvasive imaging techniques resulted in them playing a more important role in assessing myocardial perfusion influencing therapeutic decision-making and prognostication. Different imaging modalities are used to evaluate coronary perfusion, including echocardiography, coronary computerized tomography scan, magnetic resonance imaging, and nuclear myocardial perfusion imaging. Through a combination of different techniques, it is possible to describe coronary artery anatomy and the diameter of the epicardial vessels but more recently also of the coronary microcirculation. Quantification of myocardial perfusion is feasible both at baseline and during pharmacological or physiological stress. The objective of this state-of-the-art paper is to review the recent evolutions in imaging methods to estimate myocardial perfusion and to discuss the diagnostic strengths and limitations of the different techniques. The new ultrasound technologies and the hybrid approaches seem to be the future is these fields.