Increased Stress Right Ventricular ActivitY on TC99m sestamibi Perfusion SPECT A Sign Of Multivesseles And \ Or left Main Coronary Artery Disease

Abstract

Over the last decade, advancements in the field of nuclear cardiac imaging have markedly improved the diagnosis and subsequent evaluation of patients with coronary artery disease. These improvements have stemmed primarily from the development of single photon emission computed tomography (SPECT), the addition of several new Tc-99m based radiopharmaceuticals into clinical practice and the introduction of pharmacologic stressor agents.

The Aim of this study was to examine the hypothesis that increased RV uptake at stress which is not present at rest could marker for high risk CAD specifically LM. or proximal left anterior descending and circumflex CAD without concomitant proximal right coronary artery (RCA) disease.

In theory this pattern of coronary stenosis would result in global LV hypoperfusion, but allows normal perfusion of the RV with an exercise RV/LV index greater than 0.42 and an exercise to rest RV/LV index ratio of 1.2 that is, a 20% increase from rest to exercise.

This study included 30 subjects were divided into two groups; group I included 20 patients with the diagnosis of documented IHD, This group was subdivided into two subgroups: group Ia; was included ten patients with a L.M. coronary artery stenosis (or the LM equivalent; proximal LAD and LCX stenosis) of ?. 70% but no greater stenosis of the proximal right coronary artery.