Assessment of Left Ventricular Function in Coronary Artery Disease with Nuclear Techniques

Coronary Artery Disease (CAD) is the leading cause of death in many developing countries, and prevalence of the disease is increasing as economic conditions change. Early detection and prognosis using non-invasive, widely available procedures may have an impact in patient management and cast-effectiveness. The use of stress perfusion SPECT imaging represents an admitted powerful diagnostic and prognostic tool.
Patients with ischemic cardiomyopathy and severe ventricular dysfunction have poor prognosis and their management is guided mainly by the presence of myocardial viability, which defines the referral to either revascularization or medical therapy. On the other hand, patients with normal LV function are risk-stratified mainly according to the result of the perfusion scan and the extension and severity of perfusion defects. The group of patients with mild-to-moderate LV dysfunction may potentially benefit from additional parameters for a correct stratification. The purpose of our study is to investigate the feasibility, reproducibility and accuracy of early acquisition of gated perfusion SPECT after stress as compared to the routine delayed acquisition in order to improve the detectability of transient myocardial dysfunction (stunning). An additional aim is to confirm the prognostic value of myocardial stunning in a population of patients with known or suspected CAD and with mild-to-moderate ventricular dysfunction. Secondary expected outcomes are the diffusion of the technique in developing countries, as well as the improvement of skills of interpreting physicians and the awareness of the utility of the test among referring cardiologists since CAD will remain still an emerging health problem in these regions and the method would contribute to improve patient management and cost-effectiveness of medical care.