Specific Aim 4: This study will evaluate the effect of myocardial viability on mechanism of functional MR. Null Hypothesis: The mechanism of moderate MR will be no different in patients with or without myocardial viability by single photon emission computed tomography (SPECT) imaging. All patients who have undergone SPECT imaging done as part of the parent study will be studied. The grouping variables will be the presence or absence of myocardial viability as determined by the SPECT core lab.