Chapter 10

### INTRODUCTION

The non-invasive assessment of resting left ventricular (LV) performance is an integral part of the evaluation of patients with known or suspected cardiac disease, having important diagnostic, therapeutic, and prognostic significance.111 Although scintigraphic measures of cardiac function historically included measurement of ejection fraction (EF), estimation of cardiac output and valvular regurgitant fraction and detection of intracardiac shunts have also been performed. Other than EF, these potential applications for nuclear cardiology techniques have been largely supplanted by echocardiography, cardiac computed tomography, and magnetic resonance imaging (MRI) techniques over the past two decades.

Gated equilibrium radionuclide angiography (ERNA, often called multiple-gated acquisition [MUGA] and equilibrium radionuclide ventriculography [RNV]) was introduced nearly 30 years ago. It was routinely utilized in the evaluation of patients with known or suspected LV dysfunction, post-myocardial infarction (MI), and valvular disease, and for monitoring the cardiotoxic effects of chemotherapeutic drugs. Exercise radionuclide angiography (RNA), particularly with the first-pass radionuclide angiographic (FPRNA) technique, was widely used to diagnose or evaluate known coronary artery disease (CAD),59 competing favorably with and often complementing planar myocardial perfusion imaging (MPI). However, since its introduction, RNA has evolved little, while other non-invasive methods, such as gated single photon emission computed tomography (SPECT) MPI, echocardiography, and cardiac magnetic resonance, have been introduced and become increasingly sophisticated and cost effective.