Myocardial perfusion echocardiography and coronary microvascular dysfunction.

Area of Science:

• Cardiology
• Diagnostic Imaging
• Cardiovascular Physiology

Background:

• Coronary syndromes understanding has shifted from epicardial atherosclerosis to include coronary microcirculation abnormalities.
• Direct visualization of coronary microcirculation remains challenging, necessitating functional assessment methods.
• Myocardial contrast echocardiography (MCE) emerged as a key technique for evaluating myocardial perfusion.

Purpose of the Study:

• To highlight the role of Myocardial Contrast Echocardiography (MCE) in assessing coronary microcirculation.
• To demonstrate MCE's capability in quantifying myocardial perfusion and coronary blood flow.
• To evaluate MCE's diagnostic performance compared to established methods for microvascular dysfunction.

Main Methods:

• Utilized quantitative Myocardial Contrast Echocardiography (MCE) for assessing myocardial perfusion abnormalities.
• Integrated MCE with fractional flow reserve (FFR) to define ischemic burden and collateral contribution.
• Compared MCE diagnostic performance against Positron Emission Tomography (PET) for microvascular reserve.

Main Results:

• Quantitative MCE and FFR integration improved the definition of ischemic burden in non-critical stenosis.
• MCE identified no-reflow and low-flow phenomena in myocardial infarction, predicting myocardial recovery.
• MCE demonstrated diagnostic performance comparable to PET in assessing microvascular reserve and dysfunction.

Conclusions:

• Myocardial contrast echocardiography (MCE) significantly improves echocardiographic evaluations of ischemic heart disease.
• MCE provides valuable functional insights into coronary microcirculation and myocardial perfusion.
• Further regulatory approval is needed for widespread clinical adoption of MCE in daily practice.