Non-invasive imaging in detecting myocardial viability: Myocardial function versus perfusion

Abstract

Coronary artery disease (CAD) is the most prevalent and single most common cause of morbidity and mortality [1] with the resulting left ventricular (LV) dysfunction an important complication. The distinction between viable and non-viable myocardium in patients with LV dysfunction is a clinically important issue among possible candidates for myocardial revascularization. Several available non-invasive techniques are used to detect and assess ischemia and myocardial viability. These techniques include echocardiography, radionuclide images, cardiac magnetic resonance imaging and recently myocardial computed tomography perfusion imaging. This review aims to distinguish between the available non-invasive imaging techniques in detecting signs of functional and perfusion viability and identify those which have the most clinical relevance in detecting myocardial viability in patients with CAD and chronic ischemic LV dysfunction. The most current available studies showed that both myocardial perfusion and function based on non-invasive imaging have high sensitivity with however wide range of specificity for detecting myocardial viability. Both perfusion and function imaging modalities provide complementary information about myocardial viability and no optimum single imaging technique exists that can provide very accurate diagnostic and prognostic viability assessment. The weight of the body of evidence suggested that non-invasive imaging can help in guiding therapeutic decision making in patients with LV dysfunction.

Angiographic Complete versus Clinical Selective Incomplete Percutaneous Revascularization in Heart Failure Patients with Multivessel Coronary Disease

“…Myocardium with one of the following conditions was considered as nonviable tissue: Q wave in previous electrocardiogram without new ST-T changes [ 19 ]; thinning <5 mm, akinetic myocardial wall with left ventricular end-systolic volume >130 mL in echocardiography [ 20 – 22 ]; and infarction without viability detected on stress myocardial perfusion scan [ 22 ]. Myocardium with one of the following conditions was considered as viable tissue: dynamic ST-T changes in electrocardiogram [ 19 ]; left ventricular end-diastolic wall thickness ≥5 mm without features indicating non-viability in echocardiography [ 20 , 22 ]; and ischemia with viability detected on stress myocardial perfusion scan [ 22 ]. Long-term MACEs during follow-up were defined as a composite of recurrent myocardial infarction (MI), any revascularization, and all-cause mortality in 5 years.…”

A review of the Surgical Treatment for Ischemic Heart Failure trial

“…The results of both modalities were lumped together, but we also know that dobutamine stress echo has a higher specificity than single-photon-emission computed tomography, so the number of false-positive results from single-photon-emission computed tomography may have diluted the favorable effect of viability. 21 In addition, the number of patients without viability was just 114. Therefore, the study may be underpowered to detect any difference with respect to survival.…”

Comparison of Contrast Enhanced Low-Dose Dobutamine Stress Echocardiography with 99mTc-Sestamibi Single-Photon Emission Computed Tomography in Assessment of Myocardial Viability

“…Additional parameters of viability can also be assessed like strain imaging, Doppler studies, and end-diastolic wall thickness (EDWT). However, in patients with chronic ischemic ventricular dysfunction, DSE has higher specificity (78% vs 65%) but a slightly lower sensitivity (81% vs 83%) compared to SPECT [14], [15], [16].…”