Abstract 11304: Depression Predicts Higher Levels of Cardiac Sympathetic Innervation in Patients With Post Acute Coronary Syndrome - PULSE Pilot Study
BACKGROUND: Depression predicts cardiac mortality after acute coronary syndrome (ACS), and may be mediated by abnormal cardiac sympathetic activity. We hypothesized that depressed post-ACS patients would have dysregulated cardiac sympathetic innervation compared with non-depressed patients quantified by [123I]meta-iodobenzylguanidine (mIBG) imaging.
METHODS: Post-ACS patients, recruited between June 2012 and January 2013, underwent planar and single photon emission tomography (SPECT) imaging with mIBG at 25 minutes (early) and 3 hours and 50 minutes (late) after injection, along with (99mTc) sestamibi SPECT myocardial perfusion imaging (MPI). Studies were read by a blinded nuclear cardiologist, using the standard 17-segment/five point model. For identification of mIBG defects resulting from sympathetic denervation (as opposed to hypoperfusion or scar), the summed difference between late mIBG defect score and MPI defect score (mismatch score) was used as the primary outcome variable. Depressed group status was defined as Beck Depression Inventory ≥10 and non-depressed as <10.
RESULTS: Among 16 post-ACS patients, the mean mIBG-perfusion mismatch score for depressed patients was 5.50 ± 5.35 versus 13.13 ± 4.36 in non-depressed patients. In linear regression models that adjusted separately for age, gender, and left ventricular ejection fraction, depression remained significantly associated with lower mIBG-perfusion mismatch scores. Despite the small sample size, depression remained the only statistically significant predictor of mIBG-perfusion mismatch score in a multivariable model.
CONCLUSION: Depression group status was associated with higher levels of sympathetic innervation in post-ACS patients assessed by mIBG imaging, which could suggest increased sympathetic innervation in vulnerable ischemic myocardium. Further investigation is warranted.
- © 2013 by American Heart Association, Inc.