The Role of Echo in the Heart Failure Patient

The Role of Echo in the Heart Failure Patient
by Michele Bierig, MPH, BSRT, RDCS, RDMS, FSDMS, FASE

About 4.7 million people in the United States have heart failure, accounting for about 250,000 deaths per year. Echocardiography has become an integral tool in the evaluation of patients presenting with heart failure symptoms. Traditionally echo has provided a method to accurately assess ejection fraction to determine systolic dysfunction and diagnose systolic heart failure. Echocardiographically measured ejection fraction has not only been used to assess prevalence of heart failure, but also to predict mortality and outcome. Although M-mode techniques were originally used to quantify function, the studies have shown, and the American Society of Echocardiography has recommended, that sonographers measuring the function with a Simpson’s technique are more accurate. Additionally, 3D echocardiography provides the most comprehensive methods to provide a measure of the systolic dysfunction.

In addition to systolic dysfunction, more recently, impairment in diastolic filling has been found to contribute to heart failure symptoms for diastolic heart failure. In fact, patients with normal systolic function can have diastolic dysfunction as the cause of their symptoms. Around 40 percent of heart failure symptoms are due to diastolic dysfunction which can be identified using echocardiography. In the situation of diastolic dysfunction, the heart is unable to fill adequately resulting in decreased output and eventual symptoms.

Echocardiographic non-invasive measures of LV diastolic function provide a functional hemodynamic evaluation with information that aids in the prognosis and management of patients with reduced cardiac function. Diastolic Doppler indices include measurements of mitral inflow velocities; both the early filling diastolic peak and atrial wave velocities, and Tissue Doppler evaluation. Together these indices provide the most useful prognostic information. Patients with heart failure and restrictive mitral inflow filling patterns show a significantly increased mortality at 1 year and 2 year follow up when compared to those with normal filling patterns.

In summary, Echocardiography provides a non-invasive and accurate method to evaluate cardiac structure and function in normal as well as patients with heart failure symptoms.