What are the key echocardiography (echo) findings in myocardial infarction (MI)?

From the Guidelines

Echocardiography in myocardial infarction (MI) is crucial for diagnosing and assessing the extent of cardiac damage, with key findings including wall motion abnormalities, left ventricular systolic dysfunction, and mechanical complications, as recommended by the most recent guidelines 1. The most common and earliest detectable changes in MI are wall motion abnormalities, appearing as hypokinesis, akinesis, or dyskinesis in the affected myocardial segments, which typically correspond to the territory supplied by the occluded coronary artery. Some key points to consider when using echocardiography in MI include:

• Left ventricular systolic dysfunction may be present, manifested by reduced ejection fraction, which correlates with the extent of myocardial damage.
• Mechanical complications can also be identified, including ventricular septal rupture, papillary muscle rupture causing mitral regurgitation, and free wall rupture leading to cardiac tamponade.
• Right ventricular involvement may be seen in right-sided or inferior MIs.
• Diastolic dysfunction often occurs, reflecting impaired relaxation of the damaged myocardium.
• Left ventricular remodeling, characterized by chamber dilation and altered geometry, may develop over time following an MI.
• Thrombus formation within the left ventricle can be detected, particularly in anterior MIs with significant wall motion abnormalities. These findings help clinicians assess infarct size, identify complications, guide treatment decisions, and provide prognostic information for patients with myocardial infarction, as supported by recent studies 1. It is essential to note that echocardiography has a high negative predictive value for excluding acute infarction, but its positive predictive value is limited due to non-ischemic causes of wall motion abnormalities, as discussed in earlier studies 1. However, the most recent guidelines 1 prioritize the use of echocardiography in the diagnosis and management of MI, emphasizing its importance in assessing cardiac function and anatomy.

From the Research

Echocardiography Findings in Myocardial Infarction

The key echocardiography findings in myocardial infarction (MI) include:

• Left ventricular volumes and ejection fraction 2
• Wall motion score index 2, 3
• Mitral regurgitation 2, 3
• Left atrial volume 2
• Left ventricular strain (rate) and dyssynchrony 2
• Myocardial perfusion (as a marker of myocardial viability) 2
• Ischaemia and viability 2
• Coronary flow reserve 2, 4
• Left ventricular sphericity 2
• Diastolic measurements including E velocity deceleration time and E/e' ratio 4
• Speckle-tracking-derived longitudinal strain 4
• Contrast defect index 4

Detection of Mechanical Complications

Echocardiography is also useful in detecting mechanical complications of MI, such as:

• Aneurysm formation 3, 5
• Thrombus formation 3
• Infarction expansion 3
• Ventricular septal rupture 3
• Mitral regurgitation 3, 5

Prognostic Value

Echocardiography provides valuable prognostic information after MI, including:

• Risk stratification 2, 4
• Assessment of short- and long-term outcomes 2, 4
• Identification of patients at high risk for developing adverse events and mortality 4