Interpreting the change in left ventricular ejection fraction during pharmacological coronary vasodilation: Proceed with caution!

Excerpt

The left ventricular ejection fraction (LVEF) is a major determinant of outcome in patients with coronary artery disease. No matter how LVEF is measured, whether by direct contrast ventriculography, echocardiography, radionuclide angiography, gated radionuclide myocardial perfusion imaging(MPI), gated magnetic resonance imaging (MRI), or X-ray computed tomographic imaging, that relationship persists. That said, LVEF has typically been measured at rest using most of the aforementioned modalities. But when it comes to LVEF during interventions, the “playing field” becomes a lot less level. Using poetic license to lump all interventions as stress, the variations of stress LVEF include measurements during upright exercise or supine exercise (radionuclide angiography), immediately (within 60 seconds) post-exercise (Echo), delayed (>15 minutes) post-exercise (gated SPECT MPI), during a continuous intravenous dobutamine infusion (Echo and MRI), and either during (MRI) or >15 minutes following (gated SPECT MPI) an adenosine infusion or following an intravenous regadenoson injection or an intravenous dipyridamole infusion. …