Advantages and disadvantages of assessment of myocardial viability by echocardiography
Assessment of myocardial viability by echocardiography
Echo based techniques for assessment of myocardial viability has certain advantages as well as limitations. Echocardiographic techniques are safe and do not have the risk of ionizing radiation like nuclear perfusion studies and positron emission tomography. Due to portability of echocardiographic equipment even bedside evaluation is possible and the equipments are widely available. Cost of procedure is much less compared to nuclear imaging studies. Unlike cardiac magnetic resonance (CMR) imaging, presence of pacemakers and defibrillators are not a problem. Other coexisting cardiac pathology can also be assessed by echocardiography and there is a good relation between echocardiographic findings and outcome of revascularization.
Limitations for echo based assessment of myocardial viability
Both image acquisition and interpretation of images are operator dependent and there could be significant inter operator variability. Spatial resolution of echocardiography is relatively low compared to other techniques. Poor echo window like those in patients with chronic obstructive pulmonary disease can affect the diagnostic accuracy significantly. There is a tendency to underestimate viability leading to a lower sensitivity for echo based techniques.