Abstract
Shape index and eccentricity index are measures of left ventricular morphology. Although both measures can be quantified with any stress imaging modality, they are not routinely evaluated during clinical interpretation. We assessed their independent associations with major adverse cardiovascular events (MACE), including measures of post-stress change in shape index and eccentricity index. Methods: Patients undergoing single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) between 2009 and 2014 from the REFINE SPECT registry were studied. Shape index (ratio between the maximum LV diameter in short axis and ventricular length) and eccentricity index (calculated from orthogonal diameters in short axis and length) were calculated in end-diastole at stress and rest. Multivariable analysis was performed to assess independent associations with MACE (death, non-fatal myocardial infarction, unstable angina, or late revascularization). Results: In total, 14,016 patients, mean age 64.3 ± 12.2 and 8469 (60.4%) male, were included. MACE occurred in 2120 patients during a median follow-up of 4.3 years (interquartile range 3.4 – 5.7). Rest, stress, and post-stress change in shape and eccentricity indices were associated with MACE in unadjusted analyses (all p<0.001). However, in multivariable models only post-stress change in shape index (adjusted HR 1.38, p<0.001) and eccentricity index (adjusted HR 0.80, P = 0.033) remained associated with MACE. Conclusion: Two novel measures, post-stress change in shape index and eccentricity index, were independently associated with MACE and improved risk estimation. Changes in ventricular morphology have important prognostic utility and should be included in patient risk estimation following SPECT MPI.
- Cardiology (basic/technical)
- Cardiology (clinical)
- SPECT
- SPECT
- eccentricity index
- myocardial perfusion
- shape index
- ventricular morphology
- Copyright © 2021 by the Society of Nuclear Medicine and Molecular Imaging, Inc.