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 82Rb PET/CT study.
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 (82)Rb 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.


CONCLUSIONS
During (82)Rb 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.
Dorbala
Sharmila
S
Divisions of Nuclear Medicine, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA. sdorbala@partners.org
Vangala
Divya
D
Sampson
Uchechukwu
U
Limaye
Atul
A
Kwong
Raymond
R
Di Carli
Marcelo F
MF
D000328:Adult; D000368:Aged; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000503:physiopathology*; D003326:Coronary Circulation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D012414:Rubidium Radioisotopes; D013318:Stroke Volume; D014057:Tomography, X-Ray Computed; D014665:Vasodilator Agents / Q000494:pharmacology*; D016277:Ventricular Function, Left
D012414:Rubidium Radioisotopes; D014665:Vasodilator Agents