PT  - JOURNAL ARTICLE
AU  - Dorbala, Sharmila
AU  - Vangala, Divya
AU  - Sampson, Uchechukwu
AU  - Limaye, Atul
AU  - Kwong, Raymond
AU  - Di Carli, Marcelo F.
TI  - Value of Vasodilator Left Ventricular Ejection Fraction Reserve in Evaluating the Magnitude of Myocardium at Risk and the Extent of Angiographic Coronary Artery Disease: A <sup>82</sup>Rb PET/CT Study
DP  - 2007 Mar 01
TA  - Journal of Nuclear Medicine
PG  - 349--358
VI  - 48
IP  - 3
4099  - http://jnm.snmjournals.org/content/48/3/349.short
4100  - http://jnm.snmjournals.org/content/48/3/349.full
SO  - J Nucl Med2007 Mar 01; 48
AB  - Our aim was to determine the value of vasodilator left ventricular ejection fraction (LVEF) reserve (stress ejection fraction – rest ejection fraction) in evaluating the magnitude of myocardium at risk and the anatomic extent of underlying severe coronary artery disease (CAD). Methods: We studied 510 consecutive patients with suspected CAD undergoing gated rest and vasodilator stress 82Rb PET/CT. Patients were categorized as having no perfusion abnormalities, mild, moderate, or severe reversible perfusion defects. In a subgroup of 68 patients with coronary angiography, patients were categorized as having 0-vessel, 1-vessel, 2-vessel, or left main/3-vessel disease. Results: Patients without coronary risk factors who comprised our control group as well as patients with coronary risk factors and normal perfusion demonstrated a high LVEF reserve (7% ± 7% and 5% ± 6%, respectively). The mean LVEF reserve was negative (–0.2% ± 8%) in patients with severe reversible defects and in patients with 3-vessel (–6% ± 8%) and left main (–8% ± 5%) disease. Among the clinical and scintigraphic variables studied, male sex, rest ejection fraction, and increasing magnitude of myocardium at risk predicted a lower LVEF reserve, whereas LVEF reserve was the only independent predictor of left main/3-vessel disease (P = 0.008). An LVEF reserve of more than +5% had a positive predictive value of only 41% but a negative predictive value of 97% for excluding severe left main/3-vessel CAD. Conclusion: During 82Rb PET/CT, LVEF increases with vasodilator stress in patients without significant stress-induced perfusion defects or severe left main/3-vessel CAD. A high LVEF reserve appears to be an excellent tool to exclude left main/3-vessel CAD noninvasively.